+

WO2014157250A1 - Dispositif de dépôt et procédé de dépôt - Google Patents

Dispositif de dépôt et procédé de dépôt Download PDF

Info

Publication number
WO2014157250A1
WO2014157250A1 PCT/JP2014/058363 JP2014058363W WO2014157250A1 WO 2014157250 A1 WO2014157250 A1 WO 2014157250A1 JP 2014058363 W JP2014058363 W JP 2014058363W WO 2014157250 A1 WO2014157250 A1 WO 2014157250A1
Authority
WO
WIPO (PCT)
Prior art keywords
time
plasma
source gas
cylindrical hollow
hollow portion
Prior art date
Application number
PCT/JP2014/058363
Other languages
English (en)
Japanese (ja)
Inventor
知宏 前田
上坂　裕之
梅原　徳次
松井　良輔
Original Assignee
国立大学法人名古屋大学
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 国立大学法人名古屋大学 filed Critical 国立大学法人名古屋大学
Priority to JP2015508563A priority Critical patent/JPWO2014157250A1/ja
Publication of WO2014157250A1 publication Critical patent/WO2014157250A1/fr

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/50—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges
    • C23C16/511—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating using electric discharges using microwave discharges
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/04—Coating on selected surface areas, e.g. using masks
    • C23C16/045—Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/52—Controlling or regulating the coating process
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
    • H01J37/32394—Treating interior parts of workpieces
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32—Gas-filled discharge tubes
    • H01J37/32917—Plasma diagnostics
    • H01J37/32935—Monitoring and controlling tubes by information coming from the object and/or discharge
    • H01J37/32972—Spectral analysis
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/46—Generating plasma using applied electromagnetic fields, e.g. high frequency or microwave energy
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/46—Generating plasma using applied electromagnetic fields, e.g. high frequency or microwave energy
    • H05H1/461—Microwave discharges
    • H05H1/4622—Microwave discharges using waveguides

Definitions

  • the present invention relates to a method and an apparatus for forming a thin film on a wall surface of a cylindrical hollow portion by using a plasma source gas.
  • Plasma chemical vapor deposition (Chemical Vapor Deposition: CVD) method has attracted attention as a film forming technique with a uniform film thickness for improving functions such as corrosion resistance in addition to improving the cleanliness of the walls of cylindrical hollow parts such as pipes and valves. ing.
  • CVD Chemical Vapor Deposition
  • the longitudinal direction of the cylindrical hollow portion of the source gas when the rate of decomposition and consumption of the source gas by plasma formation and film formation is slow compared to the speed of the source gas supply by diffusion from the opening of the cylindrical hollow portion This distribution is not greatly affected by the presence or absence of plasma, and its uniformity can be improved.
  • Patent Document 1 as a conventional technique related to uniform film thickness, a bias system for applying a voltage bias between the workpiece and the anode so that the conductive workpiece functions as a cathode, and for monitoring the bias system are disclosed. Describes a configuration in which the intensity of plasma generated inside the workpiece is monitored using an optical probe and a Langmuir probe. However, the monitoring result is fed back to the control system that activates the introduction of the raw material gas into the workpiece. The control is extremely complicated in that the raw material gas pressure inside the workpiece is controlled by controlling the gas flow and the pumping speed in relation to the electron mean free path.
  • the negative bias voltage is used as a conventional technique for generating the inner surface plasma in a pulsed manner.
  • the negative bias voltage is used as a conventional technique for generating the inner surface plasma in a pulsed manner.
  • Patent Document 2 discloses a method of detecting a light emission intensity signal of light having a specific wavelength from active species in plasma and detecting the end of the plasma processing for the object to be processed using the signal. However, a feedback system for making the film thickness uniform is not disclosed.
  • a plasma induction means for example, a linear conductor typified by an antenna is installed inside a member to be processed to generate uniform plasma inside the member to be processed.
  • Techniques for inducing are disclosed.
  • the specific relationship between the generation of the uniform plasma and the uniformity of the film thickness formed thereby and the control thereof are not disclosed.
  • Patent Document 4 an annular member having a sufficient length for piping or the like, in which electromagnetic wave excitation plasma is induced in an internal space of the annular member to which a predetermined voltage is applied, and the object to be processed is generated by the plasma.
  • a method and apparatus for treating the inner wall surface of an annular member is disclosed.
  • a technique for forming a film with a uniform film thickness in the length direction of the annular member is not disclosed.
  • An object of the present invention is to provide an apparatus configuration and a method for forming a film with a uniform film thickness in the longitudinal direction of the cylindrical hollow portion.
  • a first invention is a film forming apparatus for forming a thin film on a wall surface of a cylindrical hollow part by using a source gas converted into plasma in the cylindrical hollow part, and the source gas species introduced into the cylindrical hollow part Or a light receiving optical system for simultaneously receiving the plasma emission of the reaction product species and the reference background gas species, and time-resolved analysis of the intensity ratio of the plasma emission from the two gas species from the light reception result, and the inside of the cylindrical hollow portion
  • a data processing unit for determining a depletion time and a recovery time of the source gas species and a time during which the inner surface plasma is generated for plasma generation (hereinafter referred to as an “inner plasma on time”).
  • the power generation control for plasma generation that controls the time during which the inner plasma is extinguished (hereinafter referred to as “the inner plasma off time”) as the recovery time or more. Characterized in that it has and.
  • a band-pass filter and a high-speed camera for selecting the wavelengths of the two gas types, a spectrometer and a light receiving element for measuring plasma emission, or a CCD camera with a spectrometer and an image intensifier, etc.
  • the combination is not limited to these.
  • a carbon-based thin film such as a diamond-like carbon film (DLC film)
  • a carbon-containing species such as C 2 or CH generated through decomposition of a source gas species
  • a reference background gas species Ar
  • the plasma emission is spectrally resolved by grating and then received by a linear array photomultiplier tube.
  • the obtained signal is subjected to time-resolved analysis processing by a computer.
  • the light receiving optical system is the slowest of the source gas species in the cylindrical hollow portion as an arbitrary measurement region of the plasma emission of the source gas species or the reaction product species thereof and the reference background gas species.
  • the cylindrical hollow portion has a straight tube shape and both ends are open and the source gas is introduced from both openings
  • the cylindrical hollow portion is equidistant from the cylindrical axis and from both ends thereof.
  • the third invention is a film forming method for forming a thin film on the wall surface of the cylindrical hollow part by using the source gas converted into plasma in the cylindrical hollow part, wherein the inner surface plasma has an on time and an off time determined as initial values.
  • a first step of starting film formation, a second step of simultaneously receiving plasma emission of the source gas species or reaction product species thereof and plasma emission of the reference background gas species by a light receiving optical system, and the light reception result The inner surface plasma within a range that does not affect the depletion time of the identified source gas species, and a third step of identifying the depletion time and recovery time of the source gas species in the cylindrical hollow portion.
  • the case where the depletion time of the source gas species is affected is, for example, that the inner surface plasma is turned off even though the source gas species contributing to film formation remain in the cylindrical hollow portion.
  • the source gas species cannot be exhausted or when the inner surface plasma is turned off, the source gas species are refilled into the cylindrical hollow portion.
  • the case where the depletion time of the source gas species becomes shorter than originally intended. In either case, the film forming rate is lowered, and the film thickness distribution in the longitudinal direction of the cylindrical hollow portion becomes a factor.
  • a thin film having a non-uniform film thickness that has been formed between the first step and the sixth step between the sixth step and the seventh step is introduced into the cylindrical hollow portion.
  • the thin film removal step of removing the thin film using the inner surface plasma of the reference background gas species that can be sputtered, and the source gas species generated by the sputtering or the reaction product species thereof The method for forming a film according to the third invention, characterized in that plasma light emission is measured by the light receiving optical system, and the completion of the thin film removal step is certified when the light emission intensity falls below a predetermined value. It is.
  • a DLC film having a non-uniform film thickness is sputtered with Ar plasma as a reference background gas species at the stage of optimizing the on-time and off-time of the inner surface plasma, and C 2 is generated at the same time.
  • the completion of removal of the DLC film is determined through monitoring of C 2 plasma emission.
  • the first invention on the basis of the monitoring result of the depleted source gas depletion, only the on / off time of the inner surface plasma generated in a pulse shape is controlled, and no other complicated control is required.
  • Patent Document 1 describes a configuration for monitoring the intensity of plasma generated inside a workpiece.
  • monitoring results are fed back to the control system that starts the introduction of the raw material gas, and the control thereof is extremely complicated.
  • the pulse shape of the inner surface plasma generated in the cylindrical hollow portion may be performed by controlling only the on time and the off time. Both are different.
  • the second aspect of the present invention it is possible to selectively monitor a local region that most effectively acts in film formation with a uniform film thickness in the longitudinal direction of the cylindrical hollow portion.
  • the optimum inner surface plasma on-time and off-time for realizing a uniform film thickness in the longitudinal direction of the cylindrical hollow portion and realizing a high film formation rate are determined by real-time measurement. Make it possible to do.
  • the columnar shape that may have been formed with a non-uniform film thickness A structure having a hollow portion can be formed again with a uniform film thickness without being discarded, and this contributes to a reduction in the total time required for the film forming process including the optimization.
  • FIG. 1A is a conceptual diagram (b) illustrating a depletion state of a source gas in a cylindrical hollow portion immediately after a negative bias voltage on-time (Ton) in a negative bias voltage application pattern, and (c). It is a graph.
  • FIG. 1B is a (b) conceptual diagram illustrating a fully-filled state of the raw material gas in the cylindrical hollow portion after the elapse of the off time (Toff) in the negative bias voltage application pattern, and (c) a graph. is there.
  • FIG. 1C illustrates (b) a conceptual diagram, (c) a graph, and (d) illustrating the distribution state of the source gas in the cylindrical hollow portion in the first half of the on-time (Ton) in the negative bias voltage application pattern.
  • FIG. 1D illustrates (a) a negative bias voltage application pattern, and (b) a conceptual diagram, (c) a graph, (d) illustrating a distribution state of a source gas in a cylindrical hollow portion in the latter half of an on-time (Ton).
  • FIG. 1D illustrates (a) a negative bias voltage application pattern, and (b) a conceptual diagram, (c) a graph, (d) illustrating a distribution state of a source gas in a cylindrical hollow portion in the latter half of an on-time (Ton).
  • FIG. 4 is a graph illustrating the influence of the ON time (Ton) of the negative bias voltage on the film thickness uniformity.
  • FIG. 5 is a graph showing the relationship between the negative bias voltage OFF time (Toff) and the source gas depletion time Td.
  • FIG. 6 is a conceptual diagram illustrating a configuration for simultaneously measuring two plasma emissions from a carbon-containing species derived from a source gas and a reference background gas species.
  • FIG. 7 is a schematic view of a film forming apparatus as one embodiment.
  • FIG. 7 schematically shows the configuration of the film forming apparatus 1 disclosed herein.
  • the film forming apparatus 1 is essentially a film forming apparatus 1 that forms a thin film on a film forming object (structure 5) by using a plasma source gas.
  • the film forming apparatus 1 is based on the so-called plasma CVD method, which forms a film by converting a raw material gas into plasma and depositing it on a film formation target.
  • this film-forming apparatus 1 is comprised so that the thin film can be formed in the wall surface with the raw material gas converted into plasma especially in the said hollow part of the film-forming target provided with a cylindrical hollow part.
  • plasma is generated by instantaneously forming an ultrahigh output field in a narrow region by superimposing a negative bias voltage on the microwave power during film formation.
  • the microwave is propagated to the wall surface of the columnar hollow portion of the film formation target, and a negative bias voltage is applied to the wall surface in a pulsed manner to superimpose the columnar hollow portion.
  • Plasma inner surface plasma
  • this film-forming apparatus 1 originates in the plasma light emission derived from the raw material gas introduce
  • the film forming apparatus 1 includes a data processing unit 11 that can perform time-resolved analysis of a light reception result and determine a depletion time and a recovery time.
  • the “depletion time” means the time from when the raw material gas is exhausted to the exhaustion from the cylindrical hollow portion in which the raw material gas is sufficiently filled.
  • the “recovery time” means the time until the source hollow is sufficiently filled in the cylindrical hollow portion in a depleted state.
  • the source gas is sufficiently filled means that the source gas concentration in the cylindrical hollow portion reaches equilibrium with the source gas concentration in the outside (typically, inside the chamber 2) atmosphere. means.
  • the film forming apparatus 1 controls the inner plasma on-time as the depletion time or more and the inner plasma off-time as the recovery time or more based on the depletion time and recovery time information obtained by the data processing unit 11.
  • a plasma generation power supply control unit 15 capable of performing the above operation is provided.
  • the technique disclosed herein generates the inner surface plasma for an appropriate time longer than the exhaustion time of the source gas in the cylindrical hollow portion, and then extinguishes the plasma for a time longer than the recovery time.
  • the film formation is started in a state where the source gas in the hollow portion is kept constant at a desired concentration.
  • film formation with a uniform thickness is realized on the inner wall of the cylindrical hollow portion.
  • FIG. 1A shows a state in which no source gas is present in the cylindrical hollow portion of the film formation target, in other words, a state in which the source gas is exhausted during the film formation process.
  • a state can be seen, for example, when the inner surface plasma is continuously generated and all the raw material gas is consumed. That is, it can be seen when the negative bias voltage is continuously turned on in the negative bias voltage application pattern (a).
  • the concentration of the source gas in the cylindrical hollow part is almost zero. In such a state, film formation using the source gas is not performed.
  • a film that has already been formed may be sputtered by a plasma such as a reference background gas.
  • a plasma such as a reference background gas.
  • FIG. 1B shows a state in which, in the film forming process, the cylindrical hollow portion of the film formation target is filled with the raw material gas to a predetermined concentration, and the raw material gas concentration is restored to the initial full state.
  • a recovery (full filling) state for example, after the negative bias is switched off in the state (A), the source gas in the chamber 2 is supplied by diffusion into the depleted cylindrical hollow portion. This is seen when the source gas concentration in the inside and the source gas concentration in the cylindrical hollow portion are substantially the same (equilibrium).
  • the film formation target is a pipe 5, and the source gas is supplied to the cylindrical hollow portion from both open ends in the axial direction of the pipe.
  • the concentration of the raw material gas is constant in the axial direction of the cylindrical hollow portion.
  • the negative bias is quickly switched on when such a recovery state is reached. That is, the inner surface plasma is generated to set the on time, and the film formation is started.
  • FIG. 1C shows a state in which the raw material gas in the cylindrical hollow portion is consumed by the generation of the inner surface plasma in the film formation process.
  • the state during the consumption is such that, by switching on the negative bias after the state (B), the inner surface plasma is generated in the cylindrical hollow portion in the recovery (full filling) state, and the source gas is consumed. You can see it when you go.
  • the plasma density phase diagram of (d) the plasma density is higher on the microwave introduction side and becomes lower as the distance from the microwave introduction side increases.
  • the concentration of the raw material gas is higher on the microwave introduction side where the plasma density is higher. It is low and increases as the plasma density decreases away from the microwave introduction side. This is because, according to the high-density plasma, the consumption of the source gas is sufficiently faster than the supply of the source gas from the chamber to the cylindrical hollow part and the diffusion in the cylindrical hollow part. It also shows that the consumption of raw material gas is ahead.
  • FIG. 1D shows a state immediately before the source gas in the cylindrical hollow portion is depleted due to the generation of internal plasma in the film formation process.
  • the state immediately before the depletion is, for example, further maintained by the inner surface plasma generated in the cylindrical hollow part by maintaining the negative bias on even after the state of consumption of the source gas in the above state (C). It can be seen when gas is consumed.
  • the concentration of the raw material gas is almost zero on the microwave introduction side. Is the extent that some amount remains on the side opposite to the microwave introduction side.
  • the source gas consumption by the high-density plasma in the cylindrical hollow portion is sufficiently faster than the supply of the source gas, and at the end opposite to the microwave introduction side
  • the source gas is exhausted as in the microwave introduction side.
  • the consumption of the raw material gas by the inner surface plasma is sufficiently faster than the supply, and even if the raw material gas can be supplied from both open ends of the cylindrical hollow portion, the supply can not keep up with the consumption. . Therefore, in the cylindrical hollow portion, the source gas is not supplied from the outside, and the source gas introduced from the beginning is consumed due to the generation of the inner surface plasma and the film formation, and thus it is inevitable that the cylindrical hollow portion falls into a depleted state. I understand that.
  • a source gas exhaustion state is not a phenomenon that occurs only when high-density plasma is used.
  • a source gas depletion state may occur depending on the size and shape of the cylindrical hollow portion, the configuration of the CVD apparatus, the setting conditions thereof, and the like.
  • the inner plasma in the film formation process, the inner plasma is immediately turned off after confirming that the source gas is exhausted in the cylindrical hollow part, and the raw material is supplied to the cylindrical hollow part. After supplying the gas until it is fully filled, the inner surface plasma is turned on again. And based on the duty cycle by ON / OFF of such inner surface plasma, it is trying to make the film thickness of the film
  • the film is formed by setting the ON time of the inner surface plasma to coincide with the depletion time from the generation of the inner surface plasma until the source gas is depleted, or by shortening it so as not to be shorter than the depletion time.
  • the rate can be improved.
  • the internal plasma off time is made to coincide with the recovery time at which the concentration of the raw material gas in the cylindrical hollow portion is sufficiently recovered, or shortened to a period close to the recovery time and optimized. The deposition rate can be improved.
  • FIGS. 2 and 3 show the plasma emission when the negative bias voltage is turned on and the inner surface plasma is generated in a state where the cylindrical hollow portion is fully filled with the source gas and the reference background gas (see, for example, FIG. 1B). Intensity changes over time.
  • FIG. 2 shows the plasma emission intensity derived from the reference background gas. In this example, Ar is used as the reference background gas.
  • FIG. 3 shows the intensity of plasma emission derived from the source gas. In this example, a carbon-containing gas is used as the source gas, and the emission intensity of C 2 as an excited species of the gas is adopted. The negative bias voltage is turned off at 3.2 ms, and the inner surface plasma is extinguished.
  • Internal plasma is generated by superimposing a negative bias voltage on the microwave power.
  • the emission spectrum of Ar is detected together with the generation of inner surface plasma (0 ms), and is almost constant until the inner surface plasma is turned off after a very short time (approximately 0.5 ms in the example of FIG. 2). It becomes the value of. Since the reference background gas that does not contribute to the film formation is not consumed, the reference background gas filled in the cylindrical hollow portion is converted into plasma and then stabilized in a very short time (about 0.5 ms). It can be seen that the amount is maintained thereafter. In addition, the time until this becomes constant depends on, for example, the type of reference background gas, the shape of the cylindrical hollow portion, and the like. One source gas plasma is consumed as the film is formed.
  • the raw material gas filled in the cylindrical hollow portion is turned into plasma in an extremely short time (in the example of FIG. 3, about 0.5 ms) to convert the raw material gas species (excited species, in this case, C 2 ).
  • the raw material gas species excited species, in this case, C 2
  • the emission intensity of the source gas species does not become zero but converges to a certain value. This is because a source gas species (C) is formed by sputtering a thin film on which a reference background gas species in the inner surface plasma and other excited species (which may be Ar ions, hydrogen atoms, and radicals) that do not contribute to film formation are formed.
  • the plasma emission intensity ratio strongly depends on the plasma emission intensity of the source gas species (C 2 ). Therefore, the time until the source gas species (C 2 ) generated from the source gas disappears, and only the source gas species (C 2 ) sputtered from the formed thin film can be detected, in other words, the inner surface plasma
  • the time from the generation until the initial determination that the value has settled to the certain value can be used as the source gas depletion time Td. Judgment whether the plasma emission intensity ratio has settled to a certain value (judgment of convergence) is unclear because it depends on the volume of the cylindrical hollow part of the film formation object and the sensitivity of the plasma emission measurement.
  • the fluctuation of the plasma emission intensity ratio is approximately 50% or less of the maximum value of the intensity ratio, typically 30% or less, further 20% or less, such as 10% or less (more preferably 5% or less, such as 2 It can be used as a guideline.
  • the change in the above-mentioned “change in the plasma emission intensity ratio” falls within 20% or less (eg, 10% or less, more preferably 5% or less, eg, about 2 to 3%) of the “change in the plasma emission intensity ratio”. It is good also as a standard.
  • time-resolved analysis of the plasma emission intensity data of the reference background gas species (Ar) and the source gas species (C 2 ) measured by the light receiving optical system 7, FIG. 2 and the depletion time Td calculated from the example of FIG. 3 was approximately 1.6 ms.
  • the gas is replenished before the raw material gas remaining in the cylindrical hollow portion is completely consumed.
  • the consumption of the raw material gas has an inclination in the cylindrical hollow portion, and therefore it takes time until this becomes uniform by diffusion.
  • the replenishment of the raw material gas is also due to diffusion, the replenishment of the raw material gas at a stage where the concentration gradient is small is inferior. Therefore, it is not preferable to start the film formation in a state where the source gas is not consumed because the film formation rate is greatly reduced.
  • the ON time of the inner surface plasma is set so as not to be shorter than the depletion time Td.
  • the inner surface plasma is turned off after the on time of the inner surface plasma becomes equal to or longer than the depletion time Td.
  • the on-time (Ton) of the inner surface plasma is determined so as to be at or near the exhaustion time of the source gas. This is a preferred embodiment. With this configuration, it is possible to form a film with a more uniform film thickness in the axial direction and with a further improved film formation rate.
  • the off time is shorter than the recovery time Tr, the source gas is not fully filled in the cylindrical hollow portion, and the amount of the reducing gas that can be used in the next film formation is reduced. Therefore, when the inner surface plasma is turned on next time, the raw material gas that can be consumed is small, and the depletion time is shortened. When the depletion time is shortened, the influence of the time required for rising of the inner surface plasma is increased, and the film formation rate is greatly reduced. In addition, the concentration of the source gas in the cylindrical hollow portion due to diffusion is not uniform, and the concentration of the source gas increases near the position where the source gas is supplied (typically, both ends in the axial direction of the cylindrical hollow portion).
  • the concentration of the raw material gas becomes lower at a position away from the supply section (typically, the central portion in the axial direction of the cylindrical hollow section). Therefore, the film thickness of the film formed in the axial direction of the cylindrical hollow portion can be nonuniform. Therefore, such film forming conditions may be a form to be avoided. Therefore, in the technique disclosed herein, it is preferable to set the internal plasma off time to be longer than the recovery time Tr. In other words, the inner surface plasma is turned on after the inner plasma off time becomes equal to or longer than the recovery time Tr. Also with this configuration, it is possible to form a film with a uniform film thickness in the axial direction and an improved film formation rate.
  • the inner plasma off time (Toff) is shortened to be at or near the recovery time Tr, and is optimal. It is a preferred embodiment. According to this configuration, the film can be formed with a more uniform film thickness in the axial direction.
  • the structure 5 having a cylindrical hollow portion can be used as a film formation target, and the hollow portion wall surface (that is, the inner wall surface) of the film formation target is used as the film formation target.
  • film formation can be performed on the inner wall surface of a cylindrical body typified by piping and valves. From the characteristics of the apparatus 1, the shape of the columnar hollow portion that is elongated or reduced in diameter so that the source gas can be depleted is a particularly suitable film formation target. .
  • Such a form in which the source gas can be exhausted cannot be unequivocally described because it depends on the configuration of the CVD apparatus, plasma generation conditions, and the like, but typically, the inner wall of a cylindrical hollow portion having a diameter of 10 mm or less is used.
  • the case where it is set as a film formation target is mentioned.
  • the inner wall of the film formation target provided with a cylindrical hollow portion having a diameter of 10 mm or less (typically 8 mm or less, more specifically 5 mm or less, for example, 4 mm or less).
  • the aspect ratio is a value expressed as b / a, where a is the diameter of the cylindrical shape of the hollow portion and b is the length in the axial direction, and the b / a is about 20 or less. It may be.
  • a film having a b / a of 1 or more, typically 2 or more, preferably 5 or more, for example, 10 or more can be a suitable film formation target.
  • the “columnar shape” is not limited to a geometrically strict columnar shape.
  • the cross-sectional shape is a columnar shape that can be regarded as a substantially round shape, it can be included in the cylindrical shape in the present technology.
  • the cross-sectional shape may include an ellipse, a polygon, and these variations.
  • the columnar central axis may be a straight line, but may be somewhat curved.
  • the basic configuration of the film forming apparatus 1 based on the plasma CVD method is not particularly limited, but for example, the configuration shown in FIG. 7 is preferably used. That is, the film forming apparatus 1 includes a chamber 2 that can form a vacuum environment for generating plasma, a gas inlet 6 for introducing a raw material gas that is a raw material of a target film into the chamber 2, and a chamber 2 A jig 4 for fixing the structure 5 to be formed into a film, a microwave generator 3 for introducing a microwave for plasma excitation into the structure 5 fixed by the jig 4, and A bias voltage power source 12 for applying a negative bias voltage to the structure 5 is provided as a main component.
  • the film forming apparatus 1 is not particularly limited, but has an electron density of 10 7 cm ⁇ 3 or more and 10 15 cm ⁇ 3 or less (typically 10 8 cm ⁇ 3 or more and 10 14 cm ⁇ 3 or less, preferably It is preferably is a 10 10 m -3 or 10 13 cm -3 or less) that can be generated in the plasma configuration.
  • the structure 5 to be formed is fixed to the jig 4, and the inside of the chamber is brought into an appropriate vacuum state, and then the source gas is introduced.
  • a microwave for plasma excitation is introduced from the microwave generator 3 to the structure 5, and a negative bias voltage is applied to the structure 5 by the bias voltage power supply 12, thereby the structure 5.
  • Plasma can be generated on the surface.
  • plasma inner surface plasma
  • plasma can be generated along the inner wall of the cylindrical hollow portion of the structure 5.
  • constituent members do not characterize the present invention and can be the same as a known configuration such as plasma CVD, and thus further description thereof is omitted.
  • the reference background gas is introduced together with the source gas to generate plasma.
  • the source gas the same source gas as that used when a film having a desired composition is formed by a conventional plasma CVD method can be used. That is, a source gas species (which can be an excited species of atoms, molecules, ions, radicals, etc. of the source gas and its reactant) capable of forming a target film by plasma excitation (including formation by reaction) is generated. As long as it can be used, it can be used without particular limitation.
  • the emission intensity derived from the source gas may be obtained by observing the emission line spectrum of any of these excited species.
  • the raw material gas when forming a DLC film, can be used alone or in combination of two or more from various carbon (C) -containing hydrocarbon gases.
  • C carbon
  • Examples of such source gas typically include methane (CH 4 ), acetylene (C 2 H 2 ), benzene (C 6 H 6 ), toluene (C 6 H 6 CH 3 ), tetramethylsilane (Tetramethylsilane).
  • TMS, Si (CH 3 ) 4 ) and the like are preferable examples.
  • silicon carbide (SiC) film When a silicon carbide (SiC) film is formed, the above-mentioned carbon-containing hydrocarbon gas, silicon-containing gas such as silane (SiH 4 ), tetramethoxysilane (Tetramethyl orthosilicate: TMOS, SiC 4 H) is used as a source gas. 12 O 4 ), alkoxysilane gas such as tetraethoxysilane (TEOS, SiC 8 H 20 O 4 ), etc., can be used alone or in combination of two or more. In this case, it is preferable to use at least one emission line spectrum of Si, SiH, H, H 2 or the like for the time-resolved analysis of the emission intensity. Further, together with these gases, a carrier gas that does not contribute to film formation can be simultaneously supplied.
  • silicon-containing gas such as silane (SiH 4 ), tetramethoxysilane (Tetramethyl orthosilicate: TMOS, SiC 4 H)
  • the reference background gas a gas that does not contribute to film formation and that can generate stable excited species by plasma excitation can be preferably used.
  • the plasma emission intensity related to the source gas is affected by slight fluctuations in the plasma flame. Therefore, by adding a reference background gas having a known concentration as an internal standard, the emission intensity of the source gas can be accurately quantified as an intensity ratio with respect to the emission intensity of the reference background gas.
  • a gas for example, a rare gas such as helium (He), neon (Ne), argon (Ar), krypton (Kr), or the like is preferable.
  • This reference background gas may serve as a carrier gas in the plasma CVD method.
  • time-resolved analysis is performed using the intensity ratio of Ar to the emission line spectrum.
  • the light receiving optical system 7 it is possible to use without particular limitation what can measure the time response characteristics of the target plasma emission intensities of two or more wavelengths in units of femtoseconds, picoseconds or nanoseconds, for example. it can.
  • the light receiving optical system 7 basically has a function of selecting light derived from the source gas and light derived from the reference background gas from plasma emission.
  • Spectroscopic means such as a bandpass filter, a grating (diffraction grating) 16 and a spectroscope, and an ultraviolet detector, a visible detector, a photodiode detector, and a photodiode array that convert the intensity of the selected light into an electric signal.
  • a light-receiving element such as a detector, a photomultiplier tube, and a linear array photomultiplier tube.
  • a light receiving optical system 7 for example, after the spectral decomposition of the light derived from the source gas and the light derived from the reference background gas by the grating (diffraction grating) 16 from the emission of the inner surface plasma, these selected spectra are used. Can be received by the linear array type photomultiplier tube 20. The obtained signal can be sent to a data processing unit 11 described later by wired or wireless communication via the optical fiber 8 or the like.
  • the light receiving optical system 7 removes excess light, for example, a mirror 18 that changes the path (optical axis) of plasma emission, a lens 17 that converges diffused light, as shown in FIG. Needless to say, a filter (not shown) or the like may be provided.
  • the linear array photomultiplier exemplified in FIG. 6 is preferably a photodiode array.
  • the light receiving optical system 7 is preferably a confocal optical system.
  • the confocal optical system can receive, with a point detector, light that has been point-illuminated on the surface of the object to be measured.
  • the light receiving element is a combination of a point detector and a pinhole having an appropriate opening.
  • the position of the lens 17 is adjusted so that the plasma emission is focused on the light receiving element from a predetermined position of the measurement object. As a result, almost all of the plasma emission from the predetermined position reaches the point detector through the pinhole and spreads without converging on the light receiving element surface. It cannot pass and is not received.
  • plasma emission at a desired position (focused position) of the cylindrical hollow portion can be obtained as a highly reliable signal without being affected by unnecessary scattered light or the like. That is, for example, by installing a confocal optical system on the axial extension of the cylindrical hollow portion and setting the focal point to an arbitrary local region (local point) of the cylindrical hollow portion, Only light emission can be received by the optical system.
  • a confocal optical system is more preferably a long-focus optical system capable of focus adjustment at a distance of 200 mm or more (typically 300 mm or more, preferably 500 mm or more, for example 700 mm or more).
  • the light receiving element may be configured by an image display device such as a high-speed camera, a CCD camera, or a streak camera provided with the light receiving element.
  • the data processing unit 11 analyzes the light reception result (signal) obtained by the light receiving optical system 7 based on time-resolved spectroscopy (TRS), and can calculate the depletion time and the recovery time.
  • Any device having a function can be used without particular limitation.
  • a computer 10 having a configuration in which a central processing unit (CPU), a main storage device, an auxiliary storage device, and the like are connected by a bus can be preferably used.
  • the source gas and the reference background in an extremely short time region (for example, about 10 ⁇ s to 1 s, preferably about 50 ⁇ s to 1 s, more preferably about 0.1 ms to 10 ms).
  • the plasma generation power control unit 15 uses the inner plasma on time as the depletion time and the inner plasma off time as the recovery time based on the depletion time and recovery time information obtained by the data processing unit 11. As long as it can be controlled as follows. For example, the frequency and duty cycle for generating the inner surface plasma are calculated from the on time and the off time in the duty ratio pulse frequency determining unit 14 and the like, and based on the frequency and duty cycle, the power source control unit 15 for plasma generation is calculated. In this way, film formation can be performed by repeatedly generating the inner surface plasma.
  • the plasma generation power source control unit 15 can be configured by, for example, a combination of a function generator 13 and a switch controller, for example.
  • the film forming method disclosed herein can be embodied as including the following steps (1) to (7).
  • the sixth step is repeated at the frequency and duty cycle calculated from the on-time and off-time of the inner surface plasma optimized to maximize the film formation rate and minimize the film thickness distribution. 7th step to film.
  • the on-time and off-time of the inner surface plasma in the steps (1) to (6) will be described based on a specific embodiment.
  • film formation is advanced by a duty cycle in which plasma is continuously turned on / off.
  • the on time and off time in the on / off state are respectively represented as Ton (n) and Toff (n).
  • Ton (n) and Toff (n) Ton
  • Toff (n) Ton
  • the on time and the off time are optimized in the first stage of the film forming cycle.
  • the generation of the inner surface plasma is realized by superimposing the microwave power introduced into the film formation target and the negative bias voltage. Therefore, in actual operation, on / off of the inner surface plasma may be controlled mainly by turning on / off the negative bias voltage.
  • Ton (1) and Toff (1) are preferably set within a range that is not too short.
  • the plasma emission of the source gas species may be emission based on any excited species included in the source gas plasma. For example, when the source gas is a carbon-containing gas (for example, CH 4 or the like), it is preferable to select and receive C 2 plasma emission.
  • the spectroscopic techniques and signal amplification techniques up to that point are There is no particular limitation.
  • the emitted light is converted into an electric signal by the light receiving optical system 7 (for example, a light receiving element) and sent to the data processing unit 11 provided in the personal computer 10, for example.
  • Step (3); Measurement of depletion time based on time-resolved analysis the data processing unit 11 performs time-resolved analysis on the light reception result sent from the light receiving optical system 7, and determines the depletion time Td of the source gas species.
  • Such data transmission / reception is preferably performed in real time.
  • the depletion time Td can be determined as follows. That is, as described above, the emission intensity based on the reference background gas (eg, Ar) and the source gas (eg, CH 4 ) converges to a constant value as the internal plasma on-time elapses, and the emission intensity ratio is Also converges to a constant value.
  • the intensity ratio decreases with the passage of the on-time of the inner surface plasma, and the fluctuation is approximately 50% or less, typically 30% or less, further 20% or less of the maximum intensity ratio, for example, When it becomes 10% or less (more preferably within 5%, for example, about 2 to 3%), it can be determined that convergence has occurred.
  • the time from plasma on (0 ms) to the convergence can be set as the first cycle depletion time Td (1).
  • Td (1) 1.6 ms was obtained as the depletion time Td (1).
  • the depletion time Td (1) is calculated by the data processing unit (calculation unit) 11 and stored in the storage unit.
  • the initial value of the on-time of the inner surface plasma is shortened and the optimum value is determined within a range that does not affect the above-determined source gas species depletion time.
  • Ton (1) Ton (1)
  • the DLC film formed in the first cycle can be peeled off by generating an inner surface plasma in a reference background gas atmosphere before performing the first cycle again.
  • Ton (1) can be made based on, for example, whether Td (1) is within a range of ⁇ 10% of Ton (1). As described above, it is generally performed in this type of algorithm that an allowable range of, for example, about ⁇ 10% may be provided for the determination.
  • the number of times the inner surface plasma is turned on / off based on Ton (1) and Toff (1) is determined by time-resolved analysis and the above-described Ton (1) from the measurement of emission intensity. It can be determined as appropriate in consideration of the time required to determine whether or not there is.
  • the number of internal plasma generations (number of on / off times) in one cycle may be adjusted according to the calculation capability of the data processing unit 11.
  • the first cycle is fixed to the number of on / off times of the inner surface plasma (for example, the number of on / off times of 10 (10 pulses) as an example) for which the data processor 11 can calculate the depletion time Td (1).
  • the number of on / off times is preferably one (one pulse).
  • the end of the first cycle can be determined when it is determined whether Ton (1) is appropriate.
  • the number of on / off operations performed in the first cycle is one, but is not limited thereto. Note that the number of plasma on / off operations performed in the following nth cycle is not strictly defined and can be set as appropriate. Hereinafter, the number of internal plasma generations (on / off times) in the n-th cycle can be similarly adjusted.
  • Toff (1) has a sufficient time to fully fill the source gas depending on whether Td (2) in the second cycle is shortened.
  • the depletion time Td in the second cycle is also based on the time decay of the emission intensity spectrum for the on-time of the second cycle in the same manner as in the first cycle (that is, in the same manner as in the second step and the third step). (2) is calculated.
  • the Td (2) data is stored in the storage unit.
  • Toff (1) is reset, and the film is formed after returning to the first cycle (that is, in the same manner as in the first to third steps).
  • the DLC film formed in the first cycle can be peeled off by generating the inner surface plasma in the reference background gas atmosphere. It is possible to form a film with a more uniform film thickness distribution in a cycle.
  • Ton (n) Ton (1), (n ⁇ 3)
  • Steps (5) and (6); Toff reduction and optimization In the fifth step, the initial value of the internal plasma off time is shortened within a range that does not affect the depletion time Td of the source gas species determined above. Then, by repeating the shortening while judging (determining) whether or not such shortening is appropriate, the optimum value of the off time of the inner surface plasma is determined. In other words, the off time is optimized by repeatedly performing the second step, the third step, and the fifth step with the determination interposed therebetween.
  • the optimization of Toff (n) can be performed from the off time of the second cycle. That is, since it has been confirmed that the initial value Toff (1) of the off time is sufficiently long in the on time of the second cycle, the off time is set to the initial value while sufficiently filling the source gas thereafter. To see how much can be shortened. In other words, the range in which the off time can be shortened without reducing the depletion time Td is examined.
  • Toff (2) a value obtained by subtracting a preset shortening period ⁇ toff from Toff (1) is adopted as Toff (2).
  • Toff (n) Toff (n ⁇ 1) ⁇ toff
  • Td (n) Td (n ⁇ 1)
  • the OFF time can be repeatedly reduced until Td (n) ⁇ Td (n ⁇ 1) in the third and subsequent cycles (n ⁇ 3).
  • Td (n) ⁇ Td (n ⁇ 1) in the third and subsequent cycles it can be determined that the previous off time Toff (n ⁇ 1) is not a sufficiently long value. For example, if Td (3) ⁇ Td (2) in the third cycle, it is considered that the off time Toff (2) of the second cycle has become too short due to the shortening. Therefore, in such a case, the off time Toff (n) in the nth cycle is added to the off time Toff (n ⁇ 2) two cycles before by adding ⁇ toff instead of reducing Toff (n ⁇ 1). return.
  • Such optimization is not particularly limited, but typically, it is preferably performed with a time of about 1/100 or less of the time required for film formation as a guide. Further, by performing 6 cycles or more (for example, 6 ⁇ n ⁇ 10), it is possible to determine the optimum Ton and Toff with higher accuracy.
  • the off time Toff (n) in the nth cycle is 2
  • the optimization may be performed based on the smaller shortening time ⁇ toff ′ from the off time Toff (n ⁇ 2) before the cycle.
  • Toff (n) is as follows.
  • Toff (n) Toff (n ⁇ 2) ⁇ toff ′
  • Td (n) Td (n ⁇ 1), n ⁇ 3
  • Toff (n) Toff (n ⁇ 2)
  • Toff (n) Toff (n ⁇ 2)
  • Toff (n) can be regarded as the recovery time Tr.
  • Step (7) Film formation under optimum conditions
  • the on-time and off-time of the inner surface plasma optimized so as to maximize the film formation rate and minimize the film thickness distribution are calculated.
  • the film is repeatedly formed at the frequency and duty cycle based on the optimized on time and off time. As a result, a film having a uniform thickness can be formed at a high rate in the axial direction of the cylindrical hollow portion.
  • the inner gas is turned on / off (switched) once to use all of the raw material gas fully filled in the hollow cylindrical portion. It is important to ensure that the raw material gas is fully filled as soon as the raw material gas is exhausted. Such filling is based only on the diffusion action of the source gas. Therefore, in the film formation by repeatedly turning on / off the inner surface plasma, it is important to suppress the problem of the diffusion of the source gas (filling failure). Therefore, it is preferable to measure the plasma emission ratio at a point where the source gas is most difficult to reach due to diffusion.
  • the light receiving optical system recovers the concentration of the source gas species at the latest in the cylindrical hollow portion as an arbitrary measurement region of the plasma emission of the source gas species or its reaction product species and the plasma emission of the reference background gas species. It may be a preferred embodiment to select the region. Such a region to be measured can typically be a point farthest from the open part of the cylindrical hollow part. Typically, for example, when the film formation target is a tubular structure and the source gas can be supplied from both ends in the tube axis direction, the measurement target region is near the center of the tubular structure in the tube axis direction. Is preferable. In order to measure only the emission intensity from such a local measurement region, it is preferable to use a confocal optical system as described above.
  • the film forming method disclosed herein may further include a thin film removing step and a step of authorizing (confirming) the completion of the thin film removing step.
  • the thin film removal step can be realized by stopping the introduction of the source gas into the chamber and generating the inner surface plasma in the atmosphere of the reference background gas species (and carrier gas).
  • the preliminarily formed thin film can be sputtered by the excited species of the reference background gas species (and carrier gas) and peeled off from the film formation target.
  • Such a peeling step can be performed at an arbitrary timing.
  • a thin film that tends to be uniform can be peeled off.
  • the step of confirming the completion of the thin film removal step is not an essential process, it is preferable to carry out the step subsequent to or in parallel with the above thin film removal step.
  • the plasma emission intensity from the source gas species derived from the thin film generated by the sputtering and the reaction product species is measured by, for example, the light receiving optical system 7, and the emission intensity is a predetermined value.
  • Completion of said thin film removal step is confirmed by being less than (threshold).
  • a threshold can be appropriately determined according to the emission intensity of the excited species derived from the thin film, the accuracy of the light receiving optical system, and the like.
  • the fluctuation of the emission intensity of the excited species derived from the thin film is 50% or less of the maximum intensity, preferably 30% or less, more preferably 20% or less, for example 10% or less (typically about 5% or less). (For example, about 3% or less), it can be determined that the removal of the thin film is completed.
  • the technique disclosed herein implements the above steps (1) to (6) under predetermined film formation conditions for a film formation target of a predetermined standard (size, material, etc.) having a cylindrical hollow portion. By doing so, it can be grasped as a method of optimizing the on-time and off-time of the inner surface plasma during film formation on the film formation target.
  • the technique disclosed herein forms a film on the inner wall of a film formation target of a predetermined standard having the cylindrical hollow portion based on the on-time and off-time of the inner surface plasma obtained by the optimization method.
  • the optimum values of the on-time and off-time are measured in advance for a desired film formation target, the optimum values of the on-time and off-time are adopted for the second and subsequent film formation. Only film formation can be performed.
  • the on-time and off-time are optimized by performing the above steps (1) to (6) for a rougher (rougher) film-forming target with a predetermined standard (dimension). Under such conditions, the film can be formed on the target film having a more precise finish.
  • the technique disclosed herein is a film forming method for forming a thin film by depositing a source gas that has been made plasma in a cylindrical hollow portion by turning on and off the plasma on the wall surface of the cylindrical hollow portion.
  • Such a film formation method can be performed by repeating on / off of the plasma in a pulsed manner based on the on-time Ton and off-time Toff of the optimized plasma.
  • this optimization process is realizable as what includes the following processes, for example.
  • Such optimization processing is performed for the on-time Ton (n) and the off-time Toff (n) of the nth cycle plasma.
  • the ON time and OFF time optimized easily are obtained.
  • the source gas is generated and extinguished in a state where the source gas and the reference background gas are introduced into the cylindrical hollow portion.
  • the above-mentioned film formation can be suitably performed by generating the plasma and depositing the plasma of the source gas on the wall surface of the cylindrical hollow portion.
  • Example 1 In this embodiment, a sufficiently long stainless steel cylindrical pipe 5 having a diameter of 1/4 inch, an inner diameter of 4.4 mm, and a length of 50 mm is prepared as a film formation target, and a DLC thin film is formed on the inner wall of the pipe 5. It was decided.
  • the film forming apparatus 1 having the configuration shown in FIG. 7 was used. The film forming procedure was as follows.
  • a DC pulse power source 12 is connected to the fixed structure 5 and a negative bias voltage is applied to the wall surface of the cylindrical hollow portion.
  • a microwave power source 3 and a waveguide for allowing microwaves to enter from the opening into the cylindrical hollow portion are connected to the chamber 2. The power of the microwave and the negative bias voltage are turned on / off with a predetermined power and voltage in response to a signal from the function generator 13.
  • the pressure in the chamber is adjusted to 30 Pa
  • the source gas such as CH 4 , C 2 H 2, benzene, toluene, tetramethylsilane, or a mixed gas thereof
  • the reference background gas are added to the chamber 2.
  • a plasma capable of separating the raw material gas species of the thin film is generated.
  • a thin film for example, a DLC film is formed on the wall surface of the cylindrical hollow portion.
  • CH 4 gas and TMS gas were used as the source gas
  • Ar gas was used as the reference gas.
  • the flow rates of these gases during film formation are CH 4 gas: 2 sccm, TMS gas: 0.2 sccm, Ar gas: 14 sccm, and a sufficient amount of source gas is filled in the pipe 5 at a uniform concentration at the start of film formation. It was in a state that has been. Further, the microwave for plasma excitation was generated under conditions of a peak power of 800 W, a frequency of 800 Hz, and a duty ratio of 10%.
  • Film formation based on the plasma CVD method is performed by turning on / off microwave power output and negative bias voltage application.
  • the on / off timing control selects plasma emission from C 2 as the carbon-containing species derived from the source gas, and determines the depletion behavior of the source gas species from the intensity ratio of the plasma emission from the reference background gas species Ar. Observe and do based on the results.
  • the observation of the depletion behavior is performed using a light receiving optical system that enables observation of the intensity ratio at an arbitrary local point in the cylindrical hollow portion.
  • the structure of the light receiving optical system 7 is various, for example, in the case of film formation on the inner surface of a stainless steel cylindrical pipe having a diameter of 1/4 inch and a length of 50 mm, it is desirable to use a confocal optical system.
  • a long-focal confocal condensing optical system is uniquely constructed following the well-known long-focus optical system so that the emission intensity of the plasma emission near the center of the pipe axis of the pipe is possible. Used.
  • confocal optics is used so that a local point on the cylinder axis is at the same distance from both ends of the structure 5. The system is adjusted.
  • the plasma emission of C 2 and Ar guided by the confocal optical system is dispersed by a grating and a movable multi-slit 19 through an optical fiber, and the intensity thereof is measured by a linear array photomultiplier tube 20 (FIG. 6).
  • a photomultiplier tube As this photomultiplier tube (PMT), a 16-channel photomultiplier tube (Hamamatsu Photonics Co., Ltd.) capable of simultaneously detecting a maximum of 16 types of wavelengths (information) dispersed through the spectroscope 9 or the like. Manufactured and specially manufactured products).
  • Other configurations include, but are not limited to, a combination of a band-pass filter and a high-speed camera for selecting the wavelengths of the two plasma emissions, or a spectroscope and a CCD camera with an image intensifier.
  • the time until the source gas species is depleted at the local point during the ON time of the inner surface plasma is determined, and the ON time of the inner surface plasma, that is, the ON state of the microwave power and the negative bias voltage is determined with reference to this.
  • the (application) time (T on ) is determined. Optimization of the T on is by Ar ions and hydrogen atoms generated by the post of the raw material gas species depletion also continue on the inner surface plasma, leading to the effect of suppressing the sputtering or etching of thin films once deposited. Also, off-time of sufficient internal surface plasma to replenish the raw material gas species consumed during T on, i.e., determining the microwave power and the negative bias voltage off (non-application) time (T off).
  • T off shortens the off time of the inner surface plasma that does not contribute to the film formation, and contributes to the improvement of the film formation rate.
  • the optimal T off may be set to a time sufficiently longer than the time required for replenishing the source gas species.
  • the optimized duty cycle based on the combination of T on and T off contributes to uniform film thickness.
  • the plasma emission intensity ratio of the Ar atoms is a reference gas species and C 2 molecule is a carbon-containing species derived from the raw material gas and time-resolved analysis, the ratio is T on (1
  • the emission intensity ratio between the C 2 molecule that is the carbon-containing species derived from the source gas in the inner surface plasma and the Ar atom that is the reference gas species converges to a constant value while the inner surface plasma is on.
  • the plasma emission intensity of the reference background gas species Ar that does not contribute to gas is almost constant because Ar is not consumed (FIG. 2), whereas the plasma emission intensity of C 2 , which is a carbon-containing species derived from the source gas, is the source gas. Although it decreases with time due to consumption, it eventually settles to a constant value (FIG. 3).
  • T d is the time until C 2 generated from the gas phase disappears, that is, the depletion time of the raw material gas, and in this embodiment, it can be determined as approximately 1.6 ms as shown in FIGS. .
  • T on (1) 250 ms.
  • T d (2) in T on (2) is calculated and stored in the same manner as in the previous step.
  • T off (2) a value obtained by subtracting a preset ⁇ t off from T off (1). That is, the following equation is satisfied. In this embodiment, it is set to 50 ms.
  • T off can be optimized more accurately by using a smaller value.
  • T off (n) T off (n ⁇ 1) ⁇ t off
  • T d (n) T d (n ⁇ 1).
  • T off (n) is added instead of reducing ⁇ t off from T off (n ⁇ 1). Return to T off (n-2) two cycles ago. That is, the following equation is satisfied.
  • Ton (n) performed in parallel is as follows.
  • T on (1) T d (1) is determined as described above.
  • T off (1) T d (1), T on (1) may not be a sufficiently long value, so the film forming process is stopped and T on (1) is reset. .
  • the effect of optimization of the T on and T off obtained through the above steps was examined under the conditions of the present embodiment.
  • the on-time (Ton) is fixed to four values in the range of 0.5 ms to 4 ms, and other conditions are the same.
  • a DLC film was formed.
  • FIG. 4 shows a result of measuring the film thickness in the axial direction of the cylindrical hollow portion of the DLC film formed at this time. The film thickness was measured at 5 mm, 25 mm, and 45 mm from the end of the pipe 5 on the side where the microwave was introduced.
  • the film thickness was in the range of 2.3 ⁇ m to 2.4 ⁇ m at any of the above positions. Film thickness distribution of the cylinder axis direction as compared to other T on is the most uniform, it can be confirmed by this effect of optimization of the T on and T off obtained through the aforementioned steps
  • FIG. 5 shows the source gas determined by measuring the plasma emission intensity of C 2 , which is a carbon-containing species derived from the source gas, at a position 25 mm from the microwave injection end for plasma excitation, with T off on the horizontal axis. It is the figure which plotted the depletion time of. As a result, exhaustion time of the feedstock gas, the case of the T off time shorter than 100ms, and to decrease in response to T off, in the case of longer than 100ms time, was almost constant (Fig. 5) .
  • T off is, since the raw material gas species lower than the time required for being refilled inside the cylindrical pipe, a predetermined raw material gas species the partial pressure (concentration) of the chamber into the T off at the measurement point This is because the time until the material gas is exhausted is shortened. That is, in this example, it is determined that the time required for recovering the partial pressure of the source gas species (that is, the recovery time Tr) is 100 ms, and in order to form a uniform film, T off is longer than 100 ms. It must be set to.
  • a DLC film having a uniform film thickness in the longitudinal direction of the cylindrical pipe is obtained by on / off control of the microwave power and the negative bias voltage by the plasma generation power supply controller using the frequency and duty cycle calculated from these as parameters. Was deposited.
  • T on and T off is the on-time of the inner surface plasma and off-time, and by extension, frequency and duty cycle for generating the internal surface plasma in pulses, with respect to the optimization process, the actual film forming process
  • frequency and duty cycle for generating the internal surface plasma in pulses with respect to the optimization process, the actual film forming process
  • the formed DLC film to introduce the process of removing using a sputtering by Ar ions. Specifically, the introduction of the source gas species into the cylindrical hollow portion is blocked, and only Ar plasma is generated. In this embodiment, the introduction of CH 4 into the chamber is interrupted, and a negative bias voltage is applied to the wall surface of the cylindrical hollow portion as the microwave is turned on.
  • the plasma emission of C 2 molecules generated by sputtering with Ar plasma is time-resolved. Then, it is determined that the DLC film has been removed when the plasma emission intensity of the C 2 molecule becomes a predetermined value or less, and the microwave application and the application of the negative bias voltage are stopped. Then as described above, it performs a negative bias voltage drive and the microwave is turned on by the plasma generation power source control unit the frequency and the duty cycle is calculated from the optimized T on and T off as a parameter, the longitudinal direction of the cylindrical hollow portion A DLC film having a uniform thickness is formed.
  • the utility value is high in the field of industrial piping materials.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Analytical Chemistry (AREA)
  • Electromagnetism (AREA)
  • Chemical Vapour Deposition (AREA)
  • Plasma Technology (AREA)

Abstract

L'invention concerne un dispositif de dépôt et un procédé de dépôt pour la formation, sur la surface de paroi d'une pièce creuse cylindrique allongée ou à facteur de forme élevé qui est une gêne pour obtenir une distribution uniforme de matière première gazeuse, d'un film ayant une épaisseur uniforme dans la direction longitudinale de la pièce creuse cylindrique. Dans ce dispositif de dépôt et ce procédé de dépôt, une lumière émise d'une espèce gazeuse de matière première transformée en plasma, ou d'espèces de produit de réaction et d'espèces de gaz de fond de celles-ci, est mesurée d'une manière à résolution temporelle à l'aide, par exemple, d'un système optique de réception de lumière par l'intermédiaire d'un système optique confocal, ce par quoi un appauvrissement de la matière première gazeuse à un point local arbitraire est surveillé en temps réel, et le résultat de la surveillance est renvoyé vers une unité de commande de source d'énergie de génération de plasma comme temporisation marche/arrêt de plasma.
PCT/JP2014/058363 2013-03-25 2014-03-25 Dispositif de dépôt et procédé de dépôt WO2014157250A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2015508563A JPWO2014157250A1 (ja) 2013-03-25 2014-03-25 成膜装置及び成膜方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2013-063113 2013-03-25
JP2013063113 2013-03-25

Publications (1)

Publication Number Publication Date
WO2014157250A1 true WO2014157250A1 (fr) 2014-10-02

Family

ID=51624217

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2014/058363 WO2014157250A1 (fr) 2013-03-25 2014-03-25 Dispositif de dépôt et procédé de dépôt

Country Status (2)

Country Link
JP (1) JPWO2014157250A1 (fr)
WO (1) WO2014157250A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117423600A (zh) * 2023-12-19 2024-01-19 哈尔滨工业大学 一种氟碳化合物等离子体基团空间分布监测装置及方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11330054A (ja) * 1998-05-20 1999-11-30 Hitachi Ltd プラズマ処理方法とその装置、並びにプラズマ処理監視装置およびプラズマ処理監視制御装置
JP2006083468A (ja) * 2004-08-31 2006-03-30 Schott Ag プロセス・パラメータの分光評価を用いた加工品のプラズマ・コーティングのための方法および装置
JP2008506840A (ja) * 2004-07-15 2008-03-06 サブ−ワン テクノロジー， インコーポレイテッド 事前に組立済みのプロセス配管の内部表面を現場においてコーティングする方法及びシステム
JP2009070735A (ja) * 2007-09-14 2009-04-02 Univ Nagoya 電磁波プラズマ発生装置、その発生方法、その表面処理装置、およびその表面処理方法。

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11330054A (ja) * 1998-05-20 1999-11-30 Hitachi Ltd プラズマ処理方法とその装置、並びにプラズマ処理監視装置およびプラズマ処理監視制御装置
JP2008506840A (ja) * 2004-07-15 2008-03-06 サブ−ワン テクノロジー， インコーポレイテッド 事前に組立済みのプロセス配管の内部表面を現場においてコーティングする方法及びシステム
JP2006083468A (ja) * 2004-08-31 2006-03-30 Schott Ag プロセス・パラメータの分光評価を用いた加工品のプラズマ・コーティングのための方法および装置
JP2009070735A (ja) * 2007-09-14 2009-04-02 Univ Nagoya 電磁波プラズマ発生装置、その発生方法、その表面処理装置、およびその表面処理方法。

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117423600A (zh) * 2023-12-19 2024-01-19 哈尔滨工业大学 一种氟碳化合物等离子体基团空间分布监测装置及方法
CN117423600B (zh) * 2023-12-19 2024-04-23 哈尔滨工业大学 一种氟碳化合物等离子体基团空间分布监测装置及方法

Also Published As

Publication number Publication date
JPWO2014157250A1 (ja) 2017-02-16

Similar Documents

Publication Publication Date Title
US10515782B2 (en) Atomic layer etching with pulsed plasmas
KR102023444B1 (ko) 플라스마 처리 장치 및 플라스마 처리 방법
Ullal et al. Effect of chamber wall conditions on Cl and Cl 2 concentrations in an inductively coupled plasma reactor
JP4909929B2 (ja) 分圧測定方法および分圧測定装置
TWI541893B (zh) Process apparatus and method for plasma etching process
CN100397038C (zh) 蚀刻量测量装置、蚀刻装置及蚀刻量测量方法
JP2013120800A (ja) 半導体装置の製造方法、半導体エッチングプロセスにおける計測方法
WO2014157250A1 (fr) Dispositif de dépôt et procédé de dépôt
JP2013187226A (ja) チャンバーのクリーニング方法、チャンバーのクリーニングの終点検出方法及びチャンバークリーニング装置
Vlcek et al. Pulsed plasmas study of linear antennas microwave CVD system for nanocrystalline diamond film growth
Saloum et al. Diagnostic study of low-pressure Ar–O2 remote plasma generated in HCD-L 300 system: relative density of O atom
JP4127435B2 (ja) 原子状ラジカル測定方法及び装置
Toader Experimental electron energy distribution functions in argon, nitrogen and oxygen high-density and low-pressure reflex and microwave plasma sources
US20240096600A1 (en) Substrate Bombardment with Ions having Targeted Mass using Pulsed Bias Phase Control
Lamara et al. Diamond thin film growth by pulsed microwave plasma at high power density in a CH4–H2 gas mixture
Matsui et al. Observation of source gas depletion in narrow metal tube during internal diamond-like carbon coating with microwaves
Shi et al. A high-activity nitrogen plasma flow source for deposition of silicon nitride films
Lee et al. High density plasma assisted sputtering system for various coating processes
US10290519B2 (en) Hot jet assisted systems and methods
Smyaglikov et al. Spectroscopic diagnostics of a pulsed arc plasma in the presence of acetylene
Dezhi et al. Modeling and experimental comparison of pulsed-DC driven low-pressure plasma discharge in a metal tube
Klimov et al. Generation of homogeneous emission plasma in a discharge system with an extended hollow cathode
JP6635586B2 (ja) 薄膜製造方法及び成膜装置
Ohta et al. Simultaneous monitoring of multimetallic atom densities in plasma processes employing a multimicrohollow cathode lamp
Han et al. Development of vacuum ultraviolet emission source using a cone-shaped O2/He hollow cathode discharge

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14775585

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2015508563

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 14775585

Country of ref document: EP

Kind code of ref document: A1

点击 这是indexloc提供的php浏览器服务，不要输入任何密码和下载