US20130161197A1

US20130161197A1 - Substrate plating apparatus and substrate plating control method

Info

Publication number: US20130161197A1
Application number: US13/721,170
Authority: US
Inventors: Jae Chan Lee
Original assignee: Samsung Electro Mechanics Co Ltd
Current assignee: Samsung Electro Mechanics Co Ltd
Priority date: 2011-12-21
Filing date: 2012-12-20
Publication date: 2013-06-27
Also published as: TW201331426A; KR101300325B1; JP2013129911A; CN103173825A; KR20130071861A; JP5524313B2

Abstract

Disclosed herein is a substrate plating apparatus, including: a constant current device supplying power; cathode hangers that includes a plurality of clamps holding substrates, hall current sensors mounted on each of the clamps to detect current information, and wireless communication modules connected with the hall current sensors to wirelessly transmit the current information to the outside; a current rail mounted with the plurality of cathode hangers above a plating bath and connected with the constant current device; and an anode unit extending from the constant current device and dipped in a plating solution of the plating bath.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2011-0139323, filed on Dec. 21, 2011, entitled “Substrate Plating Apparatus and Substrate Plating Control Method”, which is hereby incorporated by reference in its entirety into this application.

BACKGROUND OF THE INVENTION

1. Technical Field
The present invention relates to a substrate plating apparatus and a substrate plating control.
2. Description of the Related Art
In the prior art, in order to form metal wirings on a printed circuit board, wirings are formed on the board by patterning a metal film. In this case, the metal film formed on a front of the substrate is formed by using aluminum or copper. Meanwhile, copper can have large resistance force against electrical mobility while improving reliability of a semiconductor device due to a high melting point and increase a signal transfer speed due to low specific resistance. Therefore, a copper metal film has been mainly used.
As a method for forming a metal film, physical vapor deposition (PVD) using a physical conflict and chemical vapor deposition (CVD) using chemical reaction have been used. An example of the PVD may include sputtering and an example of the CVD may include thermal CVD using heat and plasma enhanced CVD (PECVD) using plasma.
However, in order to pattern the metal film on the substrate, an electroplating method having more excellent tolerance against electrical mobility and more inexpensive manufacturing costs than the deposition method has been used.
As described in Korean Patent Laid-Open Publication No. 2010-0034318 (laid-open published on Apr. 1, 2010), a principle of the electroplating according to the prior art dips a copper plate forming an anode and a substrate forming a cathode in a plating bath including an electrolyte to move copper ions Cu2+ separated from a cooper plate to the substrate so as to form a metal film.
As a general example of an electroplating method, an electroplating method using a wick hanger moves a wick hanger in which an object to be plated is mounted along a vertical or horizontal rail and dips the object to be plated in a plating solution included in a plating bath, wherein a plating object is a cathode and metal to be plated or insoluble metal is an anode.
Thereafter, the electroplating method uses a principle of attaching the plating solution to a surface of the plating object that is the cathode while separating metal ions included in the plating solution due to the electrolysis of the plating solution when current is applied to an electrode through a rectifier and performing the plating while forming a metal film when a predetermined time lapses.
The electroplating method needs to control a current density, a distribution of a plating thickness, or the like, for uniformly forming a thickness of the metal film as the printed circuit board becomes thinner.
In detail, a throwing power method issued in the prior art is described as an example. The throwing power method moves current by connecting a plurality of cathode hangers to one rectifier and holding the substrate with tongs in which clamps on the cathode hanger is divided into several branches.
However, the throwing power method is difficult to uniformly form the copper metal film on the substrate. That is, the plating area of the substrate is large, the current start varies in the hanger, and the distribution of plating current occurs on the substrate due to clamp pollution, difference in strength of clamp tongs, or the like.
The current density of the substrate is varied due to the difference in the plating current and thus, the distribution of the plating thickness is non-uniform.
Therefore, the copper metal film of the printed circuit board generally has the non-uniform distribution of the plating thickness to degrade the surface quality, thereby degrading the reliability of the printed circuit board.

SUMMARY OF THE INVENTION

The present invention has been made in an effort to provide a substrate plating apparatus capable of detecting and controlling current information for plating in real time.
Further, the present invention has been made in an effort to provide a substrate plating control method.
According to a preferred embodiment of the present invention, there is provided a substrate plating apparatus, including: a constant current device supplying power; cathode hangers that includes a plurality of clamps holding substrates, hall current sensors mounted on each of the clamps to detect current information, and wireless communication modules connected with the hall current sensors to wirelessly transmit the current information to the outside; a current rail mounted with the plurality of cathode hangers above a plating bath and connected with the constant current device; and an anode unit extending from the constant current device and dipped in a plating solution of the plating bath.
The cathode hanger may include: a horizontal support and a suspending support slidably supported to the current rail; a feeding unit disposed above the horizontal support; a conduction base coupled with the feeding unit; a rail guide provided below the suspending support; and a variable slide disposed on the rail guide, wherein the plurality of clamps fixing the substrates are mounted on the variable slide.
The wireless communication module may be mounted at one side of the suspending support.
The wireless communication module may use a local area wireless communication scheme of any one of zigbee, blue tooth, radio frequency identification (RFID), and WiFi.
The wireless communication module may include: a wireless communication processing unit connected with the hall current sensor to receive current information on each of the clamps and converting the current information into information in a local area wireless communication scheme; and a local area wireless transceiver wirelessly transmitting the converted current information to the outside.
The hall current sensor may be provided using a ring type hall device surrounding one side of the clamp.
According to another preferred embodiment of the present invention, there is provided a substrate plating control method, including: mounting a substrate to be plated using a plurality of clamps mounted on hangers; detecting current information flowing in each of the clamps by using wireless communication modules mounted on the hangers and hall current sensor mounted of each of the clamps; determining, by an external control unit, whether the current information wirelessly received in real time from the wireless communication module satisfies preset current reference information for good plating; and if it is determined that the current information satisfies the current reference information, processing, by the control unit, the substrate mounted on the corresponding hanger or the clamp as a substrate having a good plating film.
The mounting of the substrate may include: mounting the substrates to be engaged between conduction contacts of the clamps; and applying current through the clamp in a state in which the substrate is dipped in a plating solution.
The detecting of the current information in real time may include: detecting, by the hall current sensor, the current applied to each of the clamps in real time and transferring the detected current to the wireless communication module; wirelessly transmitting, by the wireless communication module, the current information to the control unit; and displaying, by the control unit, the current information by an accumulated average current value summing real time current values or average current values for each of the hangers or the clamps.
At the determining, the current reference information may include an applied current range, a current deviation range, and a current density range.
The wireless communication module may wirelessly transmit the current information by a local area wireless communication scheme of any one of zigbee, blue tooth, radio frequency identification (RFID), and WiFi.
The hall current sensor may detect the current applied to the clamp in real time by using a ring type hall device surrounding one side of the clamp.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exemplified diagram showing a substrate plating apparatus according to a preferred embodiment of the present invention;

FIG. 2 is an exemplified diagram showing a hanger of the substrate plating apparatus according to the preferred embodiment of the present invention;

FIG. 3 is an exemplified diagram showing a clamp mounted with a sensor according to a preferred embodiment of the present invention;

FIG. 4 is a block diagram of the substrate plating apparatus according to the preferred embodiment of the present invention;

FIG. 5 is a circuit diagram showing a current sensor of the substrate plating apparatus according to the preferred embodiment of the present invention;

FIG. 6 is a flow chart showing a plating control method using the substrate plating apparatus according to the preferred embodiment of the present invention;

FIG. 7 is an exemplified diagram for explaining a process of detecting current information in real time depending on the plating control method according to the preferred embodiment of the present invention; and

FIG. 8 is an exemplified diagram for explaining a process of determining plating defects depending on the plating control method according to the preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Various objects, advantages and features of the invention will become apparent from the following description of embodiments with reference to the accompanying drawings.
The terms and words used in the present specification and claims should not be interpreted as being limited to typical meanings or dictionary definitions, but should be interpreted as having meanings and concepts relevant to the technical scope of the present invention based on the rule according to which an inventor can appropriately define the concept of the term to describe most appropriately the best method he or she knows for carrying out the invention.
The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings. In the specification, in adding reference numerals to components throughout the drawings, it is to be noted that like reference numerals designate like components even though components are shown in different drawings. In the description, the terms “first”, “second”, and so on are used to distinguish one element from another element, and the elements are not defined by the above terms. In describing the present invention, a detailed description of related known functions or configurations will be omitted so as not to obscure the gist of the present invention.
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is an exemplified diagram showing a substrate plating apparatus according to a preferred embodiment of the present invention, FIG. 2 is an exemplified diagram showing a hanger of the substrate plating apparatus according to the preferred embodiment of the present invention, FIG. 3 is an exemplified diagram showing a clamp mounted with a sensor according to a preferred embodiment of the present invention, FIG. 4 is a block diagram of the substrate plating apparatus according to the preferred embodiment of the present invention, and FIG. 5 is a circuit diagram showing a current sensor of the substrate plating apparatus according to the preferred embodiment of the present invention.
As shown in FIG. 1, a substrate plating apparatus according to a preferred embodiment of the present invention may include a constant current device 10 supplying power; cathode hangers 200 that include a plurality of clamps 210 holding substrates 100, hall current sensors 212 mounted on each clamp, and wireless communication modules 220 connected with the hall current sensor 212; a current rail 20 slidably mounted with the cathode hangers 200 above a plating bath 50 and connected with the constant current device 10; and an anode unit 30 extending from the constant current device 10 and dipped in a plating solution 55 of the plating bath 50.
The substrate plating apparatus to the preferred embodiment of the present invention has a structure in which a current pass is formed of an anode unit 30 dipped in the plating solution and a current rail 20 and metal anions of the anode unit 30 move toward the substrates 100 of the cathode hangers 200 via the plating solution 55 to perform plating.
The constant current device 10 includes a plurality of anode lines and cathode lines such that the anode lines are connected with the anode unit 30 and the cathode lines are connected with the current rail 20.
The current rail 20 is provided above the plating bath 50 and the plurality of cathode hangers 200 on which the substrates 100 to be plated are mounted are slidably fastened.
As shown in FIG. 2, the cathode hanger 200 may include a horizontal support 201 and a suspending support 202 slidably supported to the current rail 20; a conduction base 204 coupled with a feeding unit 203 above the horizontal support 201; a rail guide 205 provided below the suspending support 202; a plurality of clamps 201 mounted on a variable slide 206 disposed on the rail guide 205 and fixing the substrates 100; hall current sensors 212 and 212′ mounted at one side of each clamp 210; and wireless communication modules 220 connected with hall current sensors 212 in a wired manner.
The cathode hanger 200 slidably moves on the current rail 20 by using the horizontal support 201 and the suspending support 202 to move the mounted substrate 100 in a predetermined direction and at a predetermined speed. The cathode hangers 200 may be disposed on the current rail 20 at a predetermined distance to current the same current to the substrate 100.
The clamp 210 is disposed in number set in proportion to the area or the length of the substrate 100 at a predetermined distance in a line and is used as a method for the cathode conduction while fixing the substrate 100 to be plated. As shown in FIG. 3, the conduction contact 211 of the clamp 210 is dipped in the plating solution to implement the cathode conduction for the substrate 100.
In this case, the hall current sensor 212 mounted on one side of the clamp 210 detects in real time the current information flowing in the substrate 100 through the clamp 210 and transfers the detected information to the wireless communication module 220 mounted on the suspending support 202.
The hall current sensor 212 may be formed using a ring type hall device surrounding one side of the clamp 210. As shown in FIG. 5, the hall current sensor 212 measures magnetic field for current (shown by +) flowing at a right angle by penetrating through the hall current sensor 212 to detect the current applied to the clamp 210 in real time and transfers the detected current to the wireless communication module 220 provided on the suspending support 202 in a wired manner.
The wireless communication module 220 is a module to which local area wireless communication schemes such as Zigbee, blue tooth, radio frequency identification (RFID), WiFi, or the like, are applied. The wireless communication module 220 is configured to include a local area wireless communication processing unit 221 and a local area wireless transceiver 222 as shown in FIG. 4.
The local area wireless communication processing unit 221 converts the current information transferred through wires (not shown) connected with each of the hall current sensors 212 into information in the local area wireless communication schemes and the local area wireless transceiver 222 wirelessly transfers the converted current information to a control unit (not shown) mounted on the outside. In this case, the control unit may be represented by a computer processor unit included in a PC, a PDA, a notebook, a smart phone, or the like.
The external control unit analyzes the wirelessly received current information to be display on a display device (not shown) such as a monitor, or the like as current information applied to each of the clamps 210 such as current amount flowing in each clamp 210, current density, and accumulated current amount.
Further, the control unit may compare the current information with current reference information to determine the plating defects of the plating film formed on the substrates 100 mounted on each clamp 210 and display the determined results on the display device.
Therefore, the substrate plating apparatus according to the preferred embodiment of the present invention detects the current flowing in each clamp 210 in real time by using the hall current sensor 212, thereby knowing the current information flowing in each clamp 210 and knowing the position of the clamp at which problems such as short occur.
Hereinafter, the plating control method using the substrate plating apparatus according to the preferred embodiment of the present invention will be described with reference to FIGS. 6 to 8. FIG. 6 is a flow chart showing a plating control method using the substrate plating apparatus according to the preferred embodiment of the present invention, FIG. 7 is an exemplified diagram for explaining a process of detecting current information in real time depending on the plating control method according to the preferred embodiment of the present invention, and FIG. 8 is an exemplified diagram for explaining a process of determining plating defects depending on the plating control method according to the preferred embodiment of the present invention.
The plating control method using the substrate plating apparatus according to the preferred embodiment of the present invention first mounts the substrate 100 to be plated on the cathode hanger 200 (S610).
In detail, the plating control method using the substrate plating apparatus according to the preferred embodiment of the present invention mounts the substrates 100 on the plurality of cathode hangers 200 spaced away from each other at a predetermined distance as shown in FIG. 2. In particular, the substrates 100 are mounted so as to be engaged between the conduction contacts 211 of the clamps 210.
After the substrates 100 are mounted on the plurality of clamps 210, the substrates 100 mounted on the clamps 210 vertically drops into the plating bath 50 including the plating solution to apply external power to the constant current device 10 in a state in which the substrates 100 are dipped in the plating solution 55.
When the external power is applied to the constant current device 10, the plating current performs electroplating on the substrate 100 by moving the cathode hanger 200 in one direction along the current rail 20 while supplying cathode current and anode current to the substrate 100 and the plating solution 55, respectively, through the cathode hanger 200 and the anode unit 30.
In this case, the information on current flowing in each clamp 210 is detected in real time by using the wireless communication module 220 mounted on the cathode hanger 200 and the hall current sensor 212 mounted on each clamp 210 (S620).
That is, the hall current sensor 212 detects the current applied to the clamp 210 in real time and transfers the detected current information to the wireless communication module 220 mounted on the suspending support 202 in a wired manner. The wireless communication module 220 converts the received current information into a signal pattern of the local area wireless communication scheme in the local area wireless communication processing unit 221 and wirelessly transfers the current information converted in the local area wireless transceiver 222 to the outside.
When the wirelessly transferred current information is received in the control unit mounted at the outside, the control unit may display the current information through the display device as shown in FIG. 7. That is, the control unit may display in real time a detected current value detected like a graph shown in FIG. 7 according to the wirelessly transferred current information.
Further, the control unit may display an accumulated average current value summing the average current value for each clamp as shown in FIG. 7. That is, the information that the accumulated average current summing the average current values of the current values detected for a predetermined time for each clamp from No. 1 to No. 4 of No. 96 hanger shown in FIG. 7 is 73.5 A and the accumulated average current summing the average current values detected for a predetermined time for each clamp from No. 1 to No. 4 of No. 67 hanger is 94.5 A may be displayed in real time.
As shown in FIG. 8, the control unit may represent five clamps selectively provided in No. 1 hanger by CT1 to CT5 and may display the current value detected in real time and a graph thereof Although FIG. 8 shows only No. 1 hanger, the preferred embodiment of the present invention is not limited thereto. Therefore, FIG. 8 shows the clamps for each of the plurality of hangers on which the substrates are mounted and may display the current value detected in real time and the graph thereof
In this case, the control unit determines whether the current information wirelessly transferred in real time satisfies the current reference information preset for good plating (S630).
In this case, the current reference information preset for good plating may include an applied current range, a current deviation range, a current density range, or the like. For example, when the reference input current for forming the plating thickness of 60 μm±5 μm as the determination reference is set to be 100 A, the applied current range of 90 A to 110 A that is an error range of ±10% for a 100 A value may be used as the current reference information for good plating. Therefore, the accumulated average current of No. 96 hanger shown in FIG. 7 is 73.5 A and therefore, cannot satisfy the applied current range. As a result, the control unit determines No. 96 hanger as a defective hanger and a substrate mounted on No. 96 hanger may be represented as a defective substrate.
On the other hand, the accumulated average current of No. 67 hanger is 94.5 A and therefore, satisfies the applied current range. Therefore, the control unit determines No. 67 hanger as a good hanger and may represent a substrate mounted on No. 67 hanger as a good substrate.
In addition, in FIG. 8, for the current value detected in real time and the graph thereof, the control unit may represent the hanger or the clamp by defects and the mounted substrate by defects, based on portion “A” of the graph in which the current value suddenly falls and portions “B” and “C” of the graph in which the current deviation is more serious than other clamps.
As the determination results at the determining (S630), when the wirelessly transferred current information satisfies the preset current reference information, the control unit processes the substrate mounted on the corresponding hanger or the clamp as the substrate having the good plating film (S640).
Therefore, the user may end the process of plating the processed substrate as the substrate having the good plating film and separate and finish the substrate mounted on the corresponding hanger or the clamp.
On the other hand, as the determination results at the determining (S630), when the wirelessly transferred current information does not satisfy the preset current reference information, the control unit processes the substrate mounted on the corresponding hanger or the clamp as the defective substrate and performs the discard processing (S650).
The plating control method using the substrate plating apparatus according to the preferred embodiment of the present invention including the above-mentioned process detects the information on the current applied to the clamp in real time by using the hall current sensor 212 during the electroplating.
In addition, the plating control method according to the preferred embodiment of the present invention receives in real time the current information through the local area wireless communication by the wireless communication module 220 connected with the hall current sensor 210 and displays the received current information, thereby previously preventing the non-plating defects due to current non-application and current deviation and improving the reliability of the distribution of the plating film thickness.
The plating control method using the substrate plating apparatus according to the preferred embodiments of the present invention can detect the information on the current applied to the clamp in real time by using the hall current sensor during the electroplating process.
Further, the plating control method using the substrate plating apparatus according to the preferred embodiments of the present invention can previously prevent the plating defects and can improve the reliability of the distribution of the plating film thickness by receiving in real time the current information using local area wireless communication by the wireless communication module connected with the hall current sensor and displaying the received information.
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, they are for specifically explaining the present invention and thus a substrate plating apparatus and a substrate plating control method according to the present invention are not limited thereto, but those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
In addition, any and all modifications, variations or equivalent arrangements should be considered to be within the scope of the invention, and the detailed scope of the invention will be disclosed by the accompanying claims.

Claims

What is claimed is:

1. A substrate plating apparatus, comprising:

a constant current device supplying power;

cathode hangers that includes a plurality of clamps holding substrates, hall current sensors mounted on each of the clamps to detect current information, and wireless communication modules connected with the hall current sensors to wirelessly transmit the current information to the outside;

a current rail mounted with the plurality of cathode hangers above a plating bath and connected with the constant current device; and

an anode unit extending from the constant current device and dipped in a plating solution of the plating bath.

2. The substrate plating apparatus as set forth in claim 1, wherein the cathode hanger includes:

a horizontal support and a suspending support slidably supported to the current rail;

a feeding unit disposed above the horizontal support;

a conduction base coupled with the feeding unit;

a rail guide provided below the suspending support; and

a variable slide disposed on the rail guide,

wherein the plurality of clamps fixing the substrates are mounted on the variable slide.

3. The substrate plating apparatus as set forth in claim 2, wherein the wireless communication module is mounted at one side of the suspending support.

4. The substrate plating apparatus as set forth in claim 1, wherein the wireless communication module uses a local area wireless communication scheme of any one of zigbee, blue tooth, radio frequency identification (RFID), and WiFi.

5. The substrate plating apparatus as set forth in claim 1, wherein the wireless communication module includes:

a wireless communication processing unit connected with the hall current sensor to receive current information on each of the clamps and converting the current information into information in a local area wireless communication scheme; and

a local area wireless transceiver wirelessly transmitting the converted current information to the outside.

6. The substrate plating apparatus as set forth in claim 1, wherein the hall current sensor is provided using a ring type hall device surrounding one side of the clamp.

7. A substrate plating control method, comprising:

mounting a substrate to be plated using a plurality of clamps mounted on hangers;

detecting current information flowing in each of the clamps by using wireless communication modules mounted on the hangers and hall current sensor mounted of each of the clamps;

determining, by an external control unit, whether the current information wirelessly received in real time from the wireless communication module satisfies preset current reference information for good plating; and

if it is determined that the current information satisfies the current reference information, processing, by the control unit, the substrate mounted on the corresponding hanger or the clamp as a substrate having a good plating film.

8. The subs ate plating control method as set forth in claim 7, wherein the mounting of the substrate includes:

mounting the substrates to be engaged between conduction contacts of the clamps; and

applying current through the clamp in a state in which the substrate is dipped in a plating solution.

9. The substrate plating control method as set forth in claim 7, wherein the detecting of the current information in real time includes:

detecting, by the hall current sensor, the current applied to each of the clamps in real time and transferring the detected current to the wireless communication module;

wirelessly transmitting, by the wireless communication module, the current information to the control unit; and

displaying, by the control unit, the current information by an accumulated average current value summing real time current values or average current values for each of the hangers or the clamps.

10. The substrate plating control method as set forth in claim 7, wherein at the determining, the current reference information includes an applied current range, a current deviation range, and a current density range.

11. The substrate plating control method as set forth in claim 7, wherein the wireless communication module wirelessly transmits the current information by a local area wireless communication scheme of any one of zigbee, blue tooth, radio frequency identification (RFID), and WiFi.

12. The substrate plating control method as set forth in claim 7, wherein the hall current sensor detects the current applied to the clamp in real time by using a ring type hall device surrounding one side of the clamp.