TWI358315B - Chemical filter and fan filter unit having the sam - Google Patents

Description

1358315 IX. Description of the Invention: [Technical Field] The present invention relates to a chemical filter for removing chemical contaminants contained in air supplied to a clean space and a fan having the chemical filter. Unit. More particularly, the present invention relates to a chemical filter for removing chemical contaminants contained in air provided in a clean room in which a semiconductor device manufacturing process is implemented, and a chemical filter having the same The fan passes through the unit. ® [Prior Art] In general, manufacturing semiconductor devices requires several fabrication processes, such as a fabrication process, an EDS process, and a packaging process. In the fabrication process, an electronic circuit can be fabricated on a semiconductor substrate such as a germanium wafer. An EDS process can be implemented to verify the electrical characteristics of the components and/or semiconductor devices fabricated on the semiconductor substrate. In the packaging process, the semiconductor devices are separated and encapsulated by epoxy. In the production process, several processes are required, such as a deposition process for forming a layer on a semiconductor substrate, a chemical mechanical polishing (CMP) process for planarizing the upper surface of one of the layers, An optical process for forming a photoresist pattern on the layer, an etching process for forming an electrical pattern using the photoresist pattern, and an ion implantation process for implanting predetermined impurities into a predetermined portion of the semiconductor substrate... A cleaning process for removing particles from the semiconductor substrate, an inspection process for inspecting defects of the semiconductor substrate on which the layer or the pattern is formed, and/or other processes. Typically, such semiconductor fabrication processes are implemented in a clean space such as a clean room 100485.doc 1358315. In these semiconductor device fabrication processes, a fan filter unit: 70 continuously transitions and provides clean air to the clean room. One is used for dust-free: 胄 之 之 传统 传统 传统 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing the structure of a conventional clean room system equipped with a fan filter unit, and Fig. 2 is a schematic cross-sectional view showing the structure of a conventional fan filter unit. Referring to FIG. 1, the clean room system 10 includes a clean room 12, a ceiling chamber 14 defining a top boundary of the interior of the clean room 12, and a plurality of chambers 12 disposed in a matrix shape. a fan filter unit 1 on the canopy surface, an underfloor region 16 (or a device area) defined by the floor below the clean room 12, and a connection for the underfloor region 16 and the ceiling chamber 14 An air circulation path 18, and a cooling coil 20 for controlling the temperature of the air circulated through the air circulation path 18. The clean air is supplied to the clean room 2 by the fan filter unit 1 and is discharged to the underfloor area 16' and then circulated through the air circulation path 丨8 and the ceiling chamber 14. Referring to Fig. 2, each of the fan filter units 100 includes: a fan 用于 for drawing air from the inside of the awning chamber 14, and a device for removing chemical pollution from the air sucked by the fan y . Chemical vaporizers 12,0 for ammonia (NH3) and ozone (03), and a particulate filter for removing particulates (such as dust and moisture) from the chemical filtration of the chemical filter 12 130. As shown in Fig. 2, the chemical filter 120 is disposed between the fan 110 and the particulate filter 130. The general structure of the fan filter unit 1 is also disclosed in the above-mentioned U.S. Patent No. 6,368,393, the disclosure of which is incorporated herein by reference. Since the velocity distribution of the air in the casing of the suction fan filter unit 1 can vary depending on the position, the utilization efficiency of the chemical filter 120 may be lowered. Specifically, the velocity of the air passing through the edge portion of the chemical filter 120 is caused by the chemical filter 12. The velocity of the air which is substantially higher than the air velocity passing through the central portion of the chemical filter 1 and passing through the edge portion of the chemical filter 12 will affect the life of the chemical filter 12. That is, since the air velocity in the edge portion is larger than the flow velocity in the core portion, the adsorption rate in the edge portion is substantially larger than the adsorption rate in the central portion, so that the efficiency of contaminant removal in the edge portion is lowered. Therefore, the life of the chemical filter 12 depends on the velocity distribution and velocity deviation of the air inverse particulate filter 130 as it passes through the chemical filter 120. Therefore, it is desirable to provide an improved fan passer unit for uniform air velocity distribution through the air passing through the buffer. As shown in Figures 3 and 4, an exemplary fan filter unit is disclosed in Japanese Patent Application Laid-Open No. 1999-90143. Fig. 3 is a schematic cross-sectional view showing the construction of another conventional fan filter unit, and Fig. 4 is a schematic cross-sectional view showing the construction of still another conventional fan filter unit. Referring to Figure 3, a fan filter unit 200 includes a chemical filter 21 for removing chemical contaminants contained in the air inside the canopy, and a chemical filter for chemical filtering from the chemical filter 21 The micro-particle cleaning device is used to remove particles, and a fan 22 is disposed between the chemical filter 21 and the particle transition device: 230. Between the chemical filter 210 and the fan 22A: a buffer space 240 is provided to improve the velocity profile of the air passing through the chemical filter 210. However, in the fan filter units 1〇〇 and 2〇〇 shown in Figures 2 and 3, when the chemical filter 12〇 or 21 0 is replaced, the fan filter unit i 〇〇 or 2〇0 must be completely Disassembly' therefore increases the time required for replacement work. In addition, • it may be difficult to ensure that there is a sufficient working space to increase the required time, and the downtime of the clean room system may be increased due to the interruption of the operation of the fan 11〇 or 22〇 during the replacement work. Referring to Fig. 4, a chemical filter 31 having a rectangular box shape is connected to the inlet of a fan 320, and a particulate filter 33 is connected to the outlet of the fan 32''. As shown in Fig. 4, a fan filter unit 3p can shorten the time required for the replacement of the chemical filter 310. However, there is a problem that the velocity distribution of air through the chemical filter 310 may be uneven due to the difference in air velocity between the upper portion and the side portions of the chemical filter 31. Specifically, the air velocity in the edge portion of the chemical filter 3.10 is lower than the air velocity in the planar portion of the chemical filter 310. SUMMARY OF THE INVENTION The present invention provides a chemical filter that has a uniform velocity distribution of air therethrough. • The present invention also provides a fan filter unit including the chemical filter and which can be easily replaced. According to one aspect of the invention, there is provided a chemical filter comprising: an inner circular tube having a gas permeability, an outer circular tube disposed around the inner circular tube, the chemical over 100485.doc 5 1358315 And a filter medium disposed between the interior and the outer circular tube, the filter medium for removing contaminants contained in the air flowing through the inner and outer circular tubes. The outer circular tube can also be breathable. In an exemplary embodiment of the present invention, the chemical filter may include: a first cover plate removably coupled to the inner portion and a top portion of the outer circular tube, thereby preventing air flow And a second cover plate detachably attached to the bottom portion of the inner portion and the outer circular tube. The first and second cover plates define an interior space of the inner circular tube and an intermediate space between the inner portion and the outer circular tube. The first cover may be in the shape of a disk and the second cover may have a planar annular shape including an opening that communicates with the internal space of the inner circular tube. The opening can be used as an outlet for the chemical filter. According to another aspect of the present invention, a fan filter unit including a chemical filter, a fan, and a particulate filter is provided. The chemical filter may include: an inner circular tube having gas permeability; an outer circular tube disposed around the inner circular tube, wherein the outer circular tube is also gas permeable; and a A filter medium between the outer circular tubes for removing contaminants contained in the air flowing through the inner and outer circular tubes. The fan is arranged to communicate with an interior space of one of the inner circular tubes to draw air through the outer circular tube, the filter medium and the inner circular tube. The particulate filter is coupled to the fan to remove particulates contained in the air blown by the fan. I00485.doc 1358315

In an exemplary embodiment of the invention, the suction force provided by (d) (d) may draw air (e.g., the interior air of the ceiling chamber on the clean room) to: an interior space + of one of the inner circular tubes. The suction force can be provided along the central axis of the inner circular body, and the inner space of the inner circular tube and the intermediate space between the inner portion and the outer circular tube can be removed in a removable manner The top portion of the outer circular tube is combined with a first cover to define: Thereby, the chemical filter and the inner circular shape of the crucible can be sucked by the suction force only through the outer circular tube; The inner circular shape I can be arranged in the outer circular tube in a z-axis manner, and the chemical device can be arranged with the wind shaft. Thus, the suction force can be applied uniformly to the inner circular tube, and the velocity distribution of air through the filter medium can be improved. Therefore, the life of the chemical filter can be increased. In addition, since the chemical transition stomach has a substantially cylindrical shape and is connected to the upper inlet of the fan, the time required for the chemical filter to be replaced can be shortened. According to still another aspect of the present invention, a fan filter unit including a fan, a chemical filter, and a particulate filter is provided. The fan is provided to draw air from the ceiling of the upper boundary of the clean room and to blow the air into the clean room. The fan has an inlet for suctioning the upper portion of the air and an outlet for blowing the lower portion of the air. The chemical filter is disposed on a top portion of the fan. The chemical filter comprises: a filter medium for removing chemical contaminants contained in air flowing into the clean room, the filter medium having a substantially circular tube shape; and an interior disposed in the transition medium The circular tube 'the inner circular tube has gas permeability; and one% outer circular tube disposed around the filter medium, the outer circular tube has a gas permeability of 100485.doc 1358315, and >- in the manner of the Ming P3 ten a cover plate attached to the inner and outer circular tube dome knives to prevent air from passing through the interior and the outer circular top. The space defined by the inner and outer circular tubes The upper portion of the fan is in communication with the inner space of the inner circular tube, and the air only flows through the outer circle, and the filter medium and the inner circular tube flow into the inner circular tube. In the internal space of the official. The particulate filter is coupled to the lower portion of the fan to remove particulates contained in the air blown by the fan.

The present invention will now be described more fully hereinafter with reference to the various embodiments of the present invention. The present invention may be embodied in a variety of different forms and should not be construed as limited to the embodiments described herein. Rather, the embodiments are provided so that this disclosure will be thorough and complete, and the invention will be <RTIgt; It will be understood that when an element is referred to as being "on" another element, the element may be directly on the other element or the intermediate element may be present. On the other hand, when a component is referred to as being "directly on" another component, "the phrase "and/or" is used herein, there is no intermediate element including any one or more of the associated listed items. And all combinations. It should be understood that although the terms "a" and "the" are used herein to describe various elements, such elements are not limited to such terms. These terms are only used to distinguish the elements from each other. The terminology used herein is for the purpose of describing particular embodiments, As used herein, the singular form 100485.doc •12· 1358315 The expressions “a (a)”, “an” and “the formula, #h it + (the)” are also intended to include the plural unless the context clearly . The term "part" or "bottom knife" may be used in this paper to describe the relationship of the elements shown in the figure, such as "下下.如如四四" or "top". It should be understood that the relative terms are intended to encompass different orientations of the device in addition to the orientation in the figures. For example, if its A-Ganshi I&quot; _, for example, forces the device upside down in one of the figures, it is stated that under the other components, the components on the side of the copper _ &&amp; Other elements

On the side of the cow. Therefore, the example method is called "nr _*rt", which is referred to as "the lower orientation of the lower J-end view" and includes the "lower" and "upper" orientations. Similarly, if the device in the drawings is reversed, it is stated that the elements of the following elements "below" or "below" will be "above" the other elements. Therefore, the example wording "below" $ "below" may encompass both of the above and below. Unless otherwise specified, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art. It should be further understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the related art and the present invention, and should not be in an idealized or excessive form. The meaning of the meaning is explained unless it is explicitly stated in this article. Embodiments of the present invention are described herein with reference to the accompanying drawings in which FIG. Therefore, variations in the shape of the drawings are expected to occur, for example, due to manufacturing techniques and/or tolerances. Thus, the embodiments of the invention should not be construed as limited to the particular shapes of For example, 100485.doc 13 1358315 - areas that are shown or described as flattened may generally have rough and/or non-linear features. Moreover, the sharp angles shown in the figure can usually be rounded. Therefore, the regions shown in the drawings are intended to be illustrative, and are not intended to represent the precise shapes of the regions and are not intended to limit the scope of the invention. Figure 5 is a schematic cross-sectional view showing a fan filter unit having a chemical filter in accordance with an exemplary embodiment of the present invention. Referring to Fig. 5, a fan filter unit 4 is mounted on a canopy of a clean room in which a semiconductor device manufacturing process is carried out to provide clean air into the clean room. The fan filter unit 400 includes: a chemical filter 41 for removing chemical impurities contained in the air supplied to the clean room, a fan 42 for providing suction force for the suction air, and A particulate filter 430 for removing particulates (e.g., dust and moisture) contained in the air chemically filtered by the chemical filter 410. The fan filter unit 400 is used to purify the circulating air in the clean room system, as shown generally in FIG. 1, which includes a clean room 12, a canopy room 14, an underfloor area 0, and an air circulation. Path 18 and a cooling coil 〇〇 chemical filter .4 1 0 is used to remove chemical contaminants such as ammonia, ozone or the like contained in the circulating air. The chemical filter 4 has a cylindrical outer bore 412 for receiving a filter medium 4L4. The outer casing 412 includes an inner circular tube 412A, an outer circular tube 412b, a first cover 412C and a second cover 412D. The inner and outer circular tubes 412A and 412B are breathable. Internal circular tube • 14- 1004S5.doc 8 1358315 The 412A is coaxially placed in the outer circular tube 412B. The first cover 412C is detachably attached to the top portions of the inner and outer circular tubes 412A and 412B, and the second cover 412D is detachably attached to the inner and outer circular tubes 412A and 412B. The bottom part. The inner space 412E of the inner circular tube 412A and the intermediate space 412F (see the circle 6) between the inner and outer circular tubes 4丨2A and 412B are defined by the first and second cover plates 412C and 412D. There is a disk shape, and the second cover 412E) may have a planar annular shape including an opening 412G that communicates with the inner space 412E of the inner circular tube 412A. The first cover 412C is for preventing air from flowing through the top portions of the inner and outer circular tubes 412a and 412B, and the second cover 412D is for preventing air from flowing through the bottom portions of the inner and outer tubes 412A and 412B. In other words, the first and second covers 412C and 412D are for preventing air from being introduced into the inner space 412E and the intermediate space 412F via the tubes 412A and 412; The opening 412G of the second cover 412D can be used as an outlet for the chemical filter 41. Fan 420 has an upper inlet 422 and a lower outlet 424. The second cover plate 412D is interposed between the bottom portions of the inner and outer circular tubes 412A and 412]β and the fan 420 so as to surround the upper portion 422 of the upper portion of the fan 42. In other words, the second cover 4 12D is disposed on the circumferential portion of the upper inlet 422 such that the inner space 412E of the inner circular tube 412A and the opening 412G of the second cover 412D communicate with the upper inlet 422 of the fan 420. The outer diameter of the second cover plate 412D is substantially larger than the outer circular tube 4i2B. A plurality of holes 4UH are formed circumferentially through the edge portion of the second cover plate 412D, I00485.doc 1358315 and the chemical filter 41 0 is connected to the fan by a plurality of fasteners 416 fastened to the upper portion of the fan 420 via the holes 4 12H. The upper part of 420. Further, the inner diameter of the second cover 412D is substantially equal to or smaller than the inner diameter of the inner circular tube 412, and the inner and outer circular tubes 412 and 412 are breathable. In detail, the inner and outer circular tubes 412 and 412, respectively, may include a perforated metal plate, a perforated metal plate, a metal mesh, or the like formed with a plurality of through holes. For example, the inner and outer circular tubes 412 A and 412B can be formed using perforated aluminum sheets or Ming screens, respectively. As shown in Fig. 6, although the inner and outer circular tubes 412A and 412B have a plurality of circular holes, the size or structure of the holes may vary. The chemical filter 410 is disposed coaxially with the fan 420 to maintain a uniform distance between the central axis of the fan 42 and the inner circular tube 412A. Thereby, the suction force provided by the fan 420 can be uniformly applied to the inner circular tube 412A of the chemical filter 4, and the velocity distribution of the air as it passes through the filter medium 414 can be improved. The fan 420 provides a suction force for drawing air along the central axis of the chemical filter 41, i.e., the air inside the canopy, and the air is drawn through the outer circular tube 412B, the filter, the medium 414, and the inner circular tube 412A. It enters the inner space 412E of the inner circular tube 412A. As shown in Figure 6, a pleated filter media can be used as the filter medium 414. The overlying medium 414 can have a circular tube shape and be received within the intermediate space 412F between the inner and outer circular tubes 412 A and 4 12B. The air chemically filtered by the chemical filter 410 is introduced into the particulate filter 430 via a space communicating with the lower outlet 424, so that the particulates contained in the air can be removed by the particulate filter 100485.doc. 6.5. As described, the velocity distribution of air passing through the chemical filter 410 having a cylindrical shape and having the first cover 412C is significantly improved as compared with the conventional chemical filters 12, 210, and 310 of FIGS. 2 to 4. Thereby, the life and utilization efficiency of the chemical filter 410 can be improved. Further, the chemical filter 41 is disposed on the upper inlet of the fan, so that the replacement of the chemical filter 410 can be easily performed. Also, the time required for this replacement work can be shortened. In addition, since only the filter medium 414 can be replaced after the first cover 412C is removed, the cost of the replacement work can be reduced. Table 1 shows the velocity distribution when air passes through the conventional chemical filter 120 in the conventional fan filter unit 1 of Fig. 2. The speed measurement can be performed at 36 measurement points having a rectangular plate shape having a size of about 12 mm. The measured velocity profile varies from about 3 m m/s to about 54.54 m/s and the velocity deviation is about ±24%. Table 1 Measurement position XI X2 X3 X4 X5 X6 Y1 0.46 0.31 0.41 0.35 0.44 0.44 Y2 0.44 0.38 0.41 0.35 0.38 0.37 Y3 0.41 0.47 0.49 0.39 0.49 0.46 Y4 0.37 0.39 0.40 0.41 0.41 0.41 Y5 0.37 0.37 0.37 0.36 0.33 0.36 Y6 0.54 _ . A 0.39 0.38 0.40 0.40 0.44 The conventional fan filter unit 200 in the conventional fan filter unit 200 having no buffer space 240 in Fig. 3 has a size of about 〇〇2〇〇mmxi200 mmi 100485.doc -17- 5 1358315 rectangular plate shape. The velocity profile of the air as it passes through the chemical filter 210 varies from about 0.38 m/s to about 0.48 m/s with a speed deviation of about ±12%. Figure 7 is a graph showing the velocity profile of air passing through the conventional chemical filter 210 of Figure 3 using X-axis coordinates. Referring to Fig. 7, the air velocity gradually decreases in the right and left directions from the zero (〇, 〇) point on the X-axis coordinate. This indicates that the velocity of the air passing through the central portion of the chemical transition 210 is substantially faster than the velocity of the air passing through the edge portion of the chemical filter * 210, and thus the air velocity distribution is uneven in the X-axis direction. In the conventional fan filter unit 300 equipped with a chemical filter 31 in a rectangular box shape as shown in FIG. 4, the velocity distribution measuring system is shown in FIG. 8 and Tables 2 and 3, and FIG. 8 is an X-axis coordinate display. The curve of the velocity distribution of the air as it passes through the side portion of the conventional chemical filter 3 10 shown in FIG. Referring to Figure 8, it is observed that the air passes through the side of the conventional chemical filter 3

The air velocity at the air velocity is divided and shown in Table 2 at the lateral portion of the chemical filter 3 1 , and distributed. 100485.doc -18- 1358315 Table 2 Measurement position XI X2 Y1 0.39 0.45 Y2 0.37 0.41 Y3 0.40 0.42 Y4 0.39 0.44 Table 3

Measuring position XI X2 Z1 0.17 0.21 Z2 0.18 0.19 Z3 0.19 0.23 Z4 0.20 0.21 a 0.16 Referring to Tables 2 and 3, the chemical filter 3 10 upper part of the virtual air velocity distribution is completely different from the chemical filter 3 10 The air velocity distribution at the lateral part. The air velocity distribution at the upper portion varies from about j·j7 m/s to 0.5 m/s, while on the other hand, the air velocity distribution of the meat portion of the side is about 〇·14 m. From /s to about 0.23 m/s, each 1G. In addition, the speed deviation in the upper portion is about ± 15°/〇, and the air velocity deviation at the side of the side &gt; a J is about ±35%. The air velocity distribution at the upper portion is similar to the air velocity distribution within the chemical filter 21 of the fan filter unit 200 having the buffer space 24〇. However, the air velocity distribution at the lateral portion is measured to be lower than the air velocity distribution at the upper portion, and the air velocity at the edge portion is measured 100485.doc •19- 5 135831^degree is particularly lower ^Μ §, the air velocity at the upper portion is substantially twice the air velocity, and the ratio of the maximum air velocity at the upper portion to the minimum air velocity at the upper portion is about 2.9 to about The life of the 'chemical filter 31G is reduced, and the chemical filter is 3U.) The life of the upper part can be greatly affected by the upper part of the line speed. In the opposite, at 5, the fan filter of the exemplary embodiment of the present invention is shown in FIG. 4, and the speed of the air passing through the cylindrical chemical filter is as shown in Table 4, and is uniformly measured. The velocity distribution to the circumferential direction is as shown in FIG. Table 4 Measurement position A1 A2 A3 A4 Z1 0.6 0.58 0.6 0.55 Z2 0.62 0.58 0.57 0.54 Z3 0.6 0.53 0.57 0.53 Z4 0.61 0.52 0.54 0.53 Refer to Figure 9 and Table 4 'The air velocity distribution in the chemical filter 410 is about 0 · 5 3 in / s to about 0 · 6 2 m . / s range, and the speed deviation is about ± 7%. As described above, it has been observed that the chemical filter 41 according to an exemplary embodiment of the present invention has an improved velocity distribution as compared with the conventional chemical filters 12, 210 and 3 10 . Furthermore, it has been observed that the life of the chemical filter 410 is longer than that of the conventional chemical filters 120, 210 and 3 10 . The life of the cylindrical chemical filter 410 can be practically extended by about 1% to about 2% compared to conventional chemical filters 120 and 210 having a rectangular plate shape. In addition, the cylindrical chemical filter 41 can reduce the manufacturing cost by about 1% to about 20%. Meanwhile, the chemical filter 12 of FIG. 2 has a pollutant removal efficiency of about 94.3% for pollutants such as ammonia, and The cylindrical chemical filter 41() has a pollutant removal efficiency of about 95.9%. In particular, when the chemical filter 12 is used to bleed air with a degree of contamination of about 28.5 ppb, the degree of contamination of the filtered air is about 1.71 ppb, and the pressure drop is about 2 2 mmA. At 30.6 ppb of air, the degree of contamination of the filtered air is approximately 1.24 ppb and the pressure drop is approximately 丨7 _Aq. According to the present invention, the cylindrical chemical filter draws air in a direction substantially perpendicular to the center axis of the fan, thus having an improved speed knives. In addition, the life of the chemical filter can be extended, and the utilization efficiency of the chemical can be improved. Additionally, the cylindrical chemical filtration state is coupled to the upper inlet of the fan. Therefore, the replacement of the chemical filter can be easily performed, and the time required for the replacement work can be shortened. The cost of replacing the work can be reduced by replacing only the filter media after removing the first cover. The exemplified embodiments of the present invention have been described in the foregoing description of the embodiments of the invention. The modifications are not to be taken in the spirit and scope of the invention as claimed. BRIEF DESCRIPTION OF THE DRAWINGS The above description of the present invention and its 100485.doc are considered by considering the above detailed description in conjunction with the drawings.

The features and advantages of the -2U 1358315 unit's conventional clean room will be apparent. In the drawings: Figure 1 is a schematic cross-sectional view showing a configuration equipped with a fan transition system; Figure 2 is a display _ conventional fan filter Plane section of the structure; schematic section of the conventional fan filterFig. 3 shows an alternative cross-sectional view; schematic representation of the structure of the unit

4 is a cross-sectional view showing the filter performance of a conventional fan; FIG. 4 is a schematic cross-sectional view showing the structure of a fan filter unit having a chemical filter according to an exemplary embodiment of the present invention. Figure 6 is a perspective view showing the chemical filter of Figure 5; Figure 7 is a graph illustrating the velocity distribution of air passing through the conventional chemical filter of Figure 3;

Figure 8 is a graph illustrating the velocity distribution of air passing through the side portion of the conventional chemical filter of Figure 4; Figure 9 is a graph illustrating the velocity distribution of air passing through the chemical filter of Figure 5; . [Main component symbol description] 10 Clean room system 12 Clean room 14 Canopy room 16 Underfloor area 18 Air circulation path 100485.doc 1358315

20 Cooling coil 100 Fan filter unit 110 Fan 120 Chemical filter 130 Particulate filter 200 Fan filter unit 210 Chemical filter 220 Fan 230 Particulate filter 240 Buffer space 300 Fan filter unit 310 Chemical filter 320 Fan 330 Particulate filter 400 Fan filter unit 410 Chemical filter 412 Cylindrical housing 412Α Internal circular tube 412Β External circular tube 412C First cover 412D Second cover 412Ε Internal space 412F Intermediate space 412G Opening 100485.doc ·23· 5 1358315 412H Hole 414 Filter Media 416 Fastener 420 Fan 422 Upper Entrance 424 Lower Entrance 430 Particulate Filter 100485.doc -24

Claims (1)

135831J 〇941〇84ιι No. Patent Application f 卜 Chinese Application Patent Scope Replacement (June 10, 100, Patent Application Range: 1. A chemical filter comprising: an inner circular tube having a gas permeability; An outer circular tube disposed around the inner circular tube, the outer circular tube having a gas permeability; a filter medium not disposed between the inner portion and the outer circular tube, which is used for Contaminants contained in the air inside the outer and outer circular tubes; • a first cover 'removably attached to the inner portion and the top portion of the outer circular tube' to prevent _ air from flowing through the chemical filtration a top portion of the device; and 2. a first cover plate detachably attached to the inner portion and the outer circular opening/s bottom portion, wherein the inner portion of the inner circular tube and the inner portion One of the inner and outer sides of the inner and outer circular members is defined by the first and the first cover plate and the second cover plate has a planar annular shape, one of the second cover plates The outer diameter is substantially larger than the outer circular tube 1 of the first cover The outer edge portion has an attachment member for coupling the chemical filter. The chemical filter according to claim 1, wherein the first cover has a disk shape and the second cover includes - communicates the inner circle The opening of the internal space of the tube. 3. 3. 4. According to the chemical filter of m, the inner circular tube is arranged coaxially in the outer circular tube. According to the chemical filter of claim i The inner and outer circular 100485-1000622.doc 1358315 tubes respectively comprise a perforated metal plate. 5. The chemical filter according to claim 1, wherein the inner and outer circular tubes respectively comprise a metal mesh. A fan filter unit comprising: a chemical filter comprising: an inner circular tube having a gas permeability; an outer circular tube disposed around the inner circular tube, the outer circular tube having a gas permeable And a filter medium disposed between the interior and the outer circular tube for removing contaminants contained in the air passing through the inner and outer circular tubes; a fan Connecting an inner space of the inner circular tube to suck the air passing through the outer circular tube, the filter medium and the inner circular tube; and connecting to the particulate filter of the s-black fan for cleaning The wind blows out the particles contained in the air; and a first cover plate disposed between the chemical filter and the wind to surround the upper population of the fan, wherein the inner circular tube is an inner space, and the inner and outer circular One of the intermediate spaces between the tubes is defined by the first and the second cover, wherein the second cover I shoulder-planar annular shape 'the outer diameter of one of the second cover plates is substantially larger than the outer circumference An outer diameter of the circular tube, and the chemical filter is connected to the upper portion of the fan by a plurality of fastening members, the plurality of fasteners passing over the edge of the second cover Partially fastened to the upper portion of the fan According to the fan filter unit of claim 6, further comprising a first] 00485-] 〇〇〇 622. doc S "24 / repair (more) 朁 form cover" the first cover is detachably attached To the inner portion and the top portion of the outer circular tube to prevent an air from flowing through the inner portion and the top portion of the outer circular tube. According to the fan filter unit of item 6, wherein the first cover The plate has a disk shape and the second cover includes an opening that communicates the internal space of the inner circular tube. 9. The fan filter unit of claim 6, wherein the inner circular tube is coaxially disposed on The outer circular tube. 10. The fan filter unit according to claim 6, wherein the chemical transition device is disposed coaxially with the fan. 11. The fan filter according to claim 6, the unit S' wherein the interior and the The outer circular tubes respectively comprise perforated metal sheets. 12. According to the fan filter unit of claim 6, t φ , the dry inner and the outer circular tubes respectively comprise a metal mesh. 13. A fan filter unit, Includes: a fan' For extracting an air from one of the ceiling chambers defining one of the upper boundaries of the interior, and blowing the air into the interior of the clean room The fan has a field/, for sucking the upper portion of the air inlet and a portion for blowing the lower portion of the air, and is disposed on a top portion of the fan. „A Pre-filtering, the chemical filter The utility model comprises: a filter medium, a bean for use, a main body, a servant, a _ dye, and a filter having a circular shape, which is included in the air in the interior of the clean room. a tube shape; an inner circular tube in the medium; the inner circular tube has a read*~, patrol; and an outer circular shape disposed around the 100485-1000622.doc 1358315 transition medium f a tube having a gas permeability; and - a first shy edge rolling, which is detachably attached to the inside and the outside, the top of the tube to prevent - air passing through the interior And the outer mouth p round tube of the top neighbor Qiu Ba Top. The boring tool is inserted into the inner and outer circular "the space" where the inner circular tube - the inner space is connected to the upper inlet of the fan, and the air is passed through the outer circular... The inner circular tube flows into the inner space of the inner circular tube; the particulate filter 'connects to a lower portion of the fan to divide main: the particles contained in the air blown by the wind f; and &quot a first: a cover plate disposed between the chemical filter and surrounding an upper inlet of the fan, wherein an inner space of the inner circular tube and an inner space between the inner and the outer circular tube One of the middle* is separated by the first and the second very second... - the seesaw is bounded by 'the second cover has a double-sided round % shape' and the outer diameter of one of the second covers is substantially larger than The outer diameter of the circular tube, and the servant and the _d βχ filter are connected to the upper portion of the fan by a plurality of fasteners: the plurality of fasteners: the second Fastening to the upper portion of the fan by the edge portion of the cover Wherein the inner filter train and the outer wherein the inner and the outer according to request entry of the fan filter unit 13, disposed coaxially with the fan. 15. The fan filter unit of claim 13, the circular tubes each comprising a perforated metal plate. 16. The fan filter unit of claim 13, the circular tubes each comprising a metal mesh. 100485-J000622.doc