US20150068890A1

US20150068890A1 - Substrate plating jig and plating device using same

Info

Publication number: US20150068890A1
Application number: US14/394,806
Authority: US
Inventors: Junichiro Yoshioka; Takashi Murayama
Original assignee: JCU Corp
Current assignee: JCU Corp
Priority date: 2012-04-20
Filing date: 2012-04-20
Publication date: 2015-03-12
Also published as: TW201348528A; JP5981534B2; WO2013157129A1; TWI586852B; CN104220648A; JPWO2013157129A1; CN104220648B

Abstract

A plating jig and a plating device used for plating treatment of a substrate. The plating jig includes a mechanism rotatably driving a substrate holder, and detachably mounted on a plating bath integrally with a support portion. The plating jig includes the support portion which is formed in an engageable manner with a side wall of the plating bath, and the substrate holder which is vertically rotatably mounted on the support portion. The plating jig further includes a rotary mechanism for the substrate holder. The plating device utilizes the plating jig.

Description

TECHNICAL FIELD

The present invention relates to a plating jig and a plating device used for substrate plating processing, and more particularly to a plating jig for forming a plating film on a fine wiring groove, a hole, and a resist opening portion formed on a surface to be plated of a semiconductor wafer and the like or for forming a bump (projecting electrode) which electrically connects a semiconductor chip and a substrate to each other on a surface to be plated of a semiconductor wafer, and a plating device which uses the plating jig.

BACKGROUND ART

In general, an electrolytic plating method is roughly classified into a jet-type or cup-type plating method where plating is performed such that a substrate such as a semiconductor wafer or the like is horizontally placed with a surface to be plated of the substrate facing down, and a plating solution is jetted from below, and a dip-type plating method where plating is performed such that a substrate is vertically disposed in an erected manner in a plating bath, a plating solution is jetted into the plating bath from below the plating bath, the substrate is immersed in the plating solution in the plating bath while allowing the overflow of the plating solution from the plating bath. The reason why plating is performed with the substrate disposed in a vertically erected manner in the dip-type electrolytic plating method is that bubbles generated on the surface to be plated of the substrate can be easily removed and that it is possible to make it difficult for particles or the like adhere to the surface to be plated of the substrate. In this manner, with the use of the electrolytic plating method where plating is performed with the substrate disposed in a vertically erected manner, babbles which are formed by a vigorous reduction action at the time of performing high-speed plating can be easily removed. Accordingly, this electrolytic plating method is desirable.
An electrolytic plating device which adopts the above-mentioned conventional dip-type electrolytic plating method includes a substrate holder which holds a substrate such as a semiconductor wafer in a detachable manner in a state where outer peripheral edge surfaces and a back surface of the substrate are sealed and a front surface (a surface to be plated) is exposed, and the surface to be plated of the substrate is plated by immersing the substrate holder into a plating solution together with the substrate.
However, in such a conventional electrolytic plating method which adopts dip-type plating, the substrate is immersed while holding the substrate in a vertically erected state in the plating solution, and the plating solution is made to flow in the upward direction from a lower portion of the plating bath. Accordingly, the plating solution jetted into the plating bath is always supplied toward an upper portion from a lower portion of the surface to be plated of the substrate and hence, a flow speed of the plating solution becomes non-uniform between the upper portion and the lower portion of the surface to be plated of the substrate thus giving rise to a drawback that a delicate difference occurs in film thickness of plating depending on a place of the surface to be plated of the substrate. Further, non-uniformity of current density also becomes a factor which causes non uniformity of plating.
To overcome such drawbacks, patent literatures 1, 2 disclose a plating method and a plating device where a substrate holder which holds a substrate such as a semiconductor wafer is rotated in a plating bath by a drive unit so that non-uniformity in flow speed or non-uniformity in current density of a plating solution are eliminated whereby the uniformity of a plating film thickness is increased.
However, as in the case of a plating method such as the plating method disclosed in patent literature (PTL) 1 where a shaft is connected to the substrate holder in a state where the shaft from the drive unit arranged outside the plating bath penetrates a side wall of the plating bath, sealing treatment of a penetrating portion arises as a problem to be solved. To cope with this drawback, in the method disclosed in PTL 1, sealing treatment is not applied to the penetrating portion intentionally such that the shaft and the side wall of the plating bath are brought into a non-contact state from each other, and a plating solution flows out through a gap formed between the shaft and the side wall. Such constitution, however, requires the modification of the plating bath. On the other hand, in the plating method disclosed in PTL 2, a drive shaft is arranged at a predetermined angle and hence, the drive shaft does not penetrate a side wall of a plating bath. However, it is necessary to modify the plating bath itself eventually including the arrangement of an anode plate at a predetermined angle so as to make an anode plate face an object to be plated or the formation of a bottom portion of the plating bath along an angle of the shaft.

LIST OF RELATED ART

Patent Literature

PTL 1: JP-A-2004-300462
PTL 2: JP-A-2002-327291

SUMMARY OF INVENTION

Technical Problem

Accordingly, the present invention has been made to overcome such drawbacks of the conventional plating device, and it is an object of the present invention to provide a plating jig which includes a rotation drive unit for rotatably driving a substrate holder and is detachably mountable on a plating bath without modifying the plating bath, and a plating device which utilizes the plating jig.

Solution to Problem

The present invention has been made to overcome the above-mentioned drawbacks, and provides a plating jig which is characterized by including: a support portion formed in an engageable manner with a side wall of a plating bath; and a substrate holder mounted on the support portion in a vertically rotatable manner, wherein the plating jig further includes a rotary means for rotating the substrate holder.
The present invention also provides a plating device which is characterized in that the plating jig is engageable with the side wall of the plating bath, and a paddle which is movable in a reciprocating manner in the lateral direction is arranged between the substrate holder and an anode plate which faces the substrate holder in an opposed manner.

Advantageous Effects of Invention

According to the plating jig of the present invention, the plating jig can be easily mounted on the plating device by merely making the plating jig engage with the side wall of the plating bath, a plating solution flow is used as a rotary drive unit for rotating the substrate holder, or power of a drive part is transmitted to the substrate holder by way of a rotary shaft or a gear member. None of these provisions requires the modification of the plating bath.
Further, according to the plating device provided with the plating jig of the present invention which is also provided with the paddle for agitation between the substrate holder and the anode plate, a plating solution flow which flows along a surface to be plated of the substrate can be made uniform also by the agitation generated by the paddle in addition to the rotation of the plating jig and hence, it is possible to form a plating film having a more uniform film thickness.
In the case where the plating device provided with the plating jig of the present invention is also provided with a plating solution jetting port on a bottom portion of the plating bath disposed below the substrate holder, a rotational force can be generated more efficiently by providing a difference in strength of the plating solution flow between left and right sides of the substrate holder.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 An exploded perspective view of a plating jig of the present invention.

FIG. 2 A schematic constitutional view of a plating device on which the plating jig of the present invention is mounted.

FIG. 3 (a) A side view of an outer frame member of the plating jig of the present invention.

(b) A front view of the outer frame member of the plating jig of the present invention.

FIG. 4 (a) A side view of the outer frame member of the plating jig of the present invention.

FIG. 5 (a) A side view of the outer frame member of the plating jig of the present invention.

FIG. 6 (a) A view showing a different mode of a blade portion of the outer frame member of the plating jig of the present invention.

(b) A view showing a different mode of the blade portion of the outer frame member of the plating jig of the present invention.

FIG. 7 A schematic constitutional view of the plating device on which the plating jig of the present invention is mounted.

FIG. 8 A schematic constitutional view of the plating device on which the plating jig of the present invention is mounted.

FIG. 9 A partially enlarged cross-sectional view of a substrate holder in the plating jig of the present invention.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of a plating jig of the present invention and a plating device which uses the plating jig are explained in detail by reference to drawings. The present invention is not particularly limited to the embodiments.
FIG. 1 is an exploded perspective view of the plating jig of the present invention, and FIG. 2 is a schematic constitutional view of the plating device on which the plating jig of the present invention is mounted. In the drawings, symbol 1 indicates the plating device, symbol 2 indicates the plating jig, symbol 10 indicates a plating bath, symbol 11 indicates a side wall, symbol 12 indicates a jetting port, symbol 20 indicates an overflow tank, symbol 30 indicates a substrate holder, symbol 31 indicates a holding member, symbol 32 indicates a sealing member, symbol 33 indicates an outer frame member, symbol 34 indicates a shaft portion, symbol 35 indicates a fixing bolt, symbol 36 indicates a fixing bolt, symbol 37 indicates a fixing bolt, symbol 40 indicates a support portion, symbol 41 indicates a hole portion, symbol 50 indicates an anode plate, symbol 60 indicates a paddle, symbol 70 indicates a power source, symbol 71 indicates an electricity supply path, symbol 80 indicates a piping, symbol 81 indicates a pump, symbol 82 indicates a filter, symbol 311 indicates a base portion, symbol 312 indicates a substrate mounting surface, symbol 313 indicates a hole portion, symbol 314 indicates a first electricity supply member, symbol 321 indicates an opening portion, symbol 331 indicates connecting portions, symbol 332 indicates blade portions, and symbol W indicates a substrate respectively.
As shown in the drawings, the plating jig 2 of the present invention is constituted of: the support portion 40 which is formed in an engageable manner with the side wall of the plating bath; and the substrate holder 30 which is rotatably mounted on the support portion 40. The respective portions are explained in detail by reference to FIG. 1. The support portion 40 is formed of a columnar-shaped member having an upper portion thereof formed into a hook shape such that the support portion 40 can be engaged with an upper end of the side wall of the plating bath, and the hole portion 41 into which the shaft portion 34 can be inserted is formed in a lower portion of the support portion 40. The substrate holder 30 having a disc shape is held by the hole portion 41 by way of the shaft portion 34 in a vertically rotatable manner.
The substrate holder 30 is constituted of: the holding member 31; the sealing member 32; the outer frame member 33; the shaft portion 34; and the fixing bolts 35, 36, 37. Among these components, with respect to the holding member 31, on an upper surface of the base portion 311 formed in a disc shape, the substrate mounting surface 312 having a diameter smaller than a diameter of the base portion 311 is mounted in a projecting manner. The substrate mounting surface 312 has the substantially same shape and size as the substrate W to which plating is applied. A plurality of first electricity supply members 314 are mounted on the base portion 311 around the substrate mounting surface 312 in a projecting manner. Further, the hole portion 313 into which the shaft portion 34 can be inserted is formed in a center portion of the substrate mounting surface 312.
The sealing member 32 is formed into an annular shape having the substantially same diameter as the holding member 31, and the opening portion 321 of the sealing member 32 is formed with an inner diameter slightly smaller than an outer diameter of the substrate W. On a surface of the sealing member 32 which faces the holding member 31 in an opposed manner, an annular-shaped seal packing 322 and a second electricity supply member 323 (not shown in FIG. 1) are mounted. At the time of assembling the substrate holder 30, the substrate W is sandwiched between the sealing member 32 and the holding member 31 thus sealing the first electricity supply member 314 on the base portion 311 and supplying electricity to the substrate W.
The outer frame member 33 is constituted of two members consisting of semi-annular left and right members. The outer frame member 33 has an approximately U-shaped cross section. At the time of assembling the substrate holder 30, the outer frame member 33 is fitted on outer peripheral edges of the holding member 31 and the sealing member 32. To be more specific, two outer frame members 33 are mounted on the outer peripheral edges of the holding member 31 and the sealing member 32 from left and right sides, and the outer frame members 33 are fastened and fixed to each other at upper and lower connecting portions 331 using bolts or the like. In the plating jig 2 shown in FIG. 1, the plurality of blade portions 332 are formed on an outer peripheral surface of the outer frame member 33 in a projecting manner. However, as described later, when other rotary means is used, such blade portions 332 are not always necessary.
The substrate holder 30 is mounted on the support portion 40 such that the shaft portion 34 having a threaded portion is inserted into the hole portion 313 formed in the holding member 31 and the hole portion 41 formed in the support portion 40, and the fixing bolts 35, 36, 37 are threadedly engaged with the threaded portion of the shat portion 34 thus fixing the substrate holder 30 to the support portion 40. In this case, it is desirable to seal the fixing bolt 36 which are exposed to a plating solution by applying coating or the like to the fixing bolt 36 after the bolt 36 is fixed to the shaft portion 34. Although the fixing bolt 37 is exposed to the plating solution in the same manner as the fixing bolt 36, it is desirable to form recessed portions into which the fixing bolt 37 can be embedded on a back surface of the support portion 40 as shown in FIG. 1, and to mask an opening portion of the recessed portion using a vinyl chloride plate, a tape or the like. Further, it is also desirable that coating is applied to a portion of the shaft portion 34 which is exposed to the plating solution using Teflon (registered trademark), an epoxy-system resin or the like.
Further, a method of mounting the substrate holder 30 on the support portion 40 which differs from the above-mentioned method is explained hereinafter. Firstly, the support portion 40 is formed such that the support portion 40 is split into two parts as viewed from a front side, that is, left and right members, and the recessed portion in which the shaft portion 34 and the fixing bolt 37 can be embedded is formed on the left and right members respectively. Then, the shaft portion 34 on which the fixing bolt 37 is preliminarily mounted is arranged on either one of the left and right members of the support portion 40 having the split structure, and the other member of the support portion 40 is abutted and fixed to one member thus finishing the mounting of the substrate holder 30 on the support portion 40. Due to such a mounting method, the whole length of the shaft portion 34 can be further shortened and, at the same time, as described above, it is unnecessary to seal the opening portion formed on a back side of the support portion 40.
Next, a method of supplying electricity to the substrate W is explained. An electricity supply path 71 which is embedded into the support portion 40 or drawn into the inside of the support portion 40 from a back surface supplies electricity to the shaft portion 34 via an electricity supply brush (not shown in the drawing) from the external power source 70. The shaft portion 34 is made of a conductive raw material such as a titanium material, a phosphor bronze material, a pure copper material or the like, and supplies electricity to the fixing bolt 35 which is also made of a conductive raw material. Then, electricity is supplied to the first electricity supply members 314 via an electricity supply paths (not shown in the drawing) which is embedded in the inside of the holding member 31 from the fixing bolts 35, 36 provided for fixing the holding member 31.
FIG. 9 is a partially-enlarged view showing a conduction mode in a state where the substrate holder 30 is assembled while sandwiching the substrate W between the sealing member 32 and the holding member 31. As shown in FIG. 9, on a surface of the sealing member 32 which faces the holding member 31 in an opposed manner, the annular seal packing 322 and the second electricity supply member 323 are mounted. The seal packing 322 has a U-shaped cross-sectional shape where a length of an upper and a length of lower side differ from each other. The second electricity supply member 323 is formed into a flat disc shape. A plurality of projecting contact points 324 are formed on an inner periphery of the second electricity supply member 323 in a projecting manner. At the time of assembling the substrate holder 30, a flat plate portion of the second electricity supply member 323 is brought into contact with the first electricity supply member 314 mounted on the base portion 311, and the projecting contact points 324 are brought into contact with a plated surface of the substrate W. Due to such a constitution, electricity can be supplied to the substrate W from the first electricity supply member 314 via the second electricity supply member 323. The above-mentioned conducting method is desirable from a viewpoint that electricity can be surely supplied to the substrate W without exposing the first electricity supply member 314 and the second electricity supply member 323 into the plating solution due to the seal packing 322. However, a method of supplying electricity to the plating jig of the present invention is not limited to the above-mentioned method.
Next, the rotary means for the substrate holder 30 is explained. As the rotary means for the substrate holder 30 in the plating jig 2 of the present invention, a method which makes use of the flow of plating solution by providing blade portions or recessed portions on an outer peripheral surface of the outer frame member or a method which rotates the substrate holder 30 by a drive part can be adopted. FIG. 3( a) and FIG. 3( b) show the constitution where blade portions 332 are formed on the outer peripheral surface of the outer frame member 33 in a projecting manner. As shown in the drawings, with respect to the rotary means of this embodiment, the plurality of blade portions 332 having a rectangular-plate shape are formed on the outer peripheral surface of the outer frame member 33 equidistantly. The blade portion 332 is formed on the outer peripheral surface in an approximately vertically erected manner, and a blade portion is arranged horizontally as viewed in a side view. The rotary means where the blade portions are mounted on the outer frame member 33 can generate a rotational force when a plaiting solution flow impinges on the blade portions 332 so that the substrate holder 30 can be rotated.
FIG. 4 (a) and FIG. 4 (b) show blade portions 333 formed in a different mode. As shown in the drawings, the blade portions 333 are formed on an outer peripheral surface of the outer frame member 33 in an approximately vertically-erected manner. However, the blade portions 333 are not arranged horizontally but are arranged with an angle such that the blade portions 333 are inclined downwardly from a front side to a rear side. By giving such angle to the blade portions 333 in this manner, the rotary means can catch the flow of plating solution from a front side more effectively. Further, by forming the blade portion into an approximately U shape or an approximately V shape instead of a rectangular plate shape, as shown in FIG. 6 (a) and FIG. 6 (b), the rotary means can catch the flow of plating solution more easily.
FIG. 5 (a) and FIG. 5 (b) show the rotary means where recessed portions 334 are formed on an outer peripheral surface of an outer frame member 33 in a recessed manner. As shown in the drawings, in this embodiment, the plurality of recessed portions 334 each having a rectangular shape are formed on the outer peripheral surface of the outer frame member 33 equidistantly. In this manner, by forming the recessed portions 334 on the outer peripheral surface of the outer frame member 33, the recessed portions catch the flow of the plating solution in the same manner as the blade portions and can generate a rotational force so that the substrate holder 30 can be rotated.
FIG. 7 shows a first mode of rotating a substrate holder 30 by a drive part. As shown in FIG. 7, a rotational force is transmitted to a gear 93 mounted on a shaft portion 34 by way of a shaft 91 from a drive part 90 such as an electrically-operated motor. The gear 34 transmits a rotational force of the shaft 91 to the shaft portion 34 while converting the rotation of the shaft 91 into the rotation of the shaft portion 34. Accordingly, the substrate holder 30 can be rotated. The drive part 90 may be directly mounted on the support portion 40, or may be detachably mounted on a mounting portion 92. An additional support portion may be provided outside a plating bath for supporting the drive part 90. The transmission of a rotational force to the shaft portion 34 from the drive part 90 may be, besides the transmission using the combination of the shaft and the gear as in the case of this embodiment, the transmission using the combination of a plurality of gear members, or the transmission using a belt.
FIG. 8 shows a second mode of rotating a substrate holder 30 by a drive part. As shown in FIG. 8, a gear portion 94 is mounted on an upper portion of the substrate holder 30, and a gear 95 having the same pitch as the gear portion 94 is mounted on an outer frame member of the substrate holder 30. When a rotational force is transmitted to the gear portion 94 from the drive part 90, the rotational force is transmitted to the gear 95 mounted on the outer frame member so that the substrate holder 30 can be rotated. The transmission of a rotational force to the gear portion 94 from the drive part 90 may be the transmission using the combination of the shaft and the gear as in the case of the first embodiment, the transmission using the combination of a plurality of gear members or the transmission using a belt.
The rotary means for the substrate holder 30 is not limited to either one of the above-mentioned methods, that is, the method which makes use of the flow of plating solution by forming the blade portions or the recessed portions on the outer peripheral surface of the outer frame member 33, and the method which rotates the substrate holder 30 by the drive part, and the rotary means may be combination of these rotary means. That is, a rotational force may be imparted to the substrate holder 30 by forming the blade portions or the recessed portions on the outer peripheral surface of the outer frame member 33 and, at the same time, a rotational force may be imparted to the substrate holder 30 by using an external drive part. In this manner, with the use of two kinds of different rotational forces, the rotation of the substrate holder 30 can be made further stable thus suppressing the power consumption.
Next, a plating device which uses the plating jig 2 of the present invention is explained. FIG. 2 is a schematic constitutional view of the plating device 1 on which the plating jig 2 of the present invention is mounted. As shown in FIG. 2, the plating device 1 of the present invention includes the plating bath 10, and the overflow tank 20 arranged on an outer periphery of the plating bath 10. The plating jig 2 is mounted on the side wall 11 of the plating bath 10. In the inside of the plating bath 10, the anode plate 50 is arranged at a position facing a plated surface of the substrate W held by the substrate holder 30 in an opposed manner. The paddle 60 may be arranged between the anode plate 50 and the substrate holder 30 as in the case of this embodiment. The paddle 60 can make the flow of plating solution along the plated surface of the substrate uniform by moving in a reciprocating manner parallel to the plated surface of the substrate W. Accordingly, a plating film having a further uniform film thickness can be formed by a synergistic effect brought about by the paddle 60 and the substrate holder 30 having the rotary means. From the above reasons, the provision of the paddle 60 is desirable.
A jetting port 12 to which the piping 80 is connected is formed in the bottom portion of the plating bath 10, and a plating solution is supplied into the inside of the plating bath 10 through the jetting port 12. When the jig which makes use of the flow of the plating solution by forming the blade portions or the recessed portions on the outer peripheral surface of the outer frame members shown in FIG. 1 and FIG. 3 to FIG. 6 is utilized, it is desirable to arrange the jetting port 12 at a position where the flow of plating solution can effectively transmit a rotational force to the blade portions or the recessed portions of the outer frame member 33. To be more specific, it is desirable to arrange the jetting port 12 below the substrate holder 30 and along the direction parallel to the substrate holder 30. In this case, by providing the jetting port 12 to only one side of the plating bath 10 or by making jetting amounts of the plating solution from the jetting ports 12 different from each other between the left and right sides so as to make a strength of the flow of plating solution different between the left and right sides of the substrate holder 30, a rotational force can be generated more efficiently. Accordingly, it is desirable to adopt such a constitution.

REFERENCE SIGNS LIST

1: plating device
2: plating jig
10: plating bath
11: side wall
12: jetting port
20: overflow tank
30: substrate holder
31: holding member
32: sealing member
33: outer frame member
34: shaft portion
35: fixing bolt
36: fixing bold
37: fixing bolt
40: support portion
41: hole portion
50: anode plate
60: paddle
70: power source
71: electricity supply path
80: piping
81: pump
82: filter
90: drive part
91: shaft
92: mounting portion
93: gear
94: gear portion
95: outer frame member
311: base portion
312: substrate mounting surface
313: hole portion
314: first electricity supply member
321: opening portion
322: seal packing
323: second electricity supply member
324: projecting contact point
331: connection portion
332: blade portion
333: blade portion
334: recessed portion
W: substrate

Claims

1-9. (canceled)

10. A plating jig comprising:

a support portion detachably engaged with a side wall of a plating bath;

a substrate holder held on the support portion in a vertically rotatable manner;

a rotary means for the substrate holder which utilizes a flow of plating solution; and

a rotary means for the substrate holder which is rotated by a drive part;

or a combination of the rotary means for the substrate holder which utilizes the flow of the plating solution and the rotary means for the substrate holder which is rotated by the drive part.

11. The plating jig according to claim 10, wherein the substrate holder comprises:

a holding member including a substrate mounting surface;

an annular sealing member configured to sandwich the substrate between the sealing member and the holding member;

an outer frame member configured to be fitted on peripheries of the holding member and the sealing member; and

a shaft portion configured to be inserted into a hole portion formed in a center portion of the holding member.

12. The plating jig according to claim 11, wherein the rotary means for the substrate holder includes a blade portion formed on an outer peripheral surface of the outer frame member of the substrate holder in a projecting manner.

13. The plating jig according to claim 11, wherein the rotary means for the substrate holder includes a recessed portion formed on an outer peripheral surface of the outer frame member of the substrate holder.

14. The plating jig according to claim 11, wherein the rotary means for the substrate holder is configured to transmit a rotational force to the shaft portion of the substrate holder by a rotary shaft of a drive part mounted on the support portion.

15. The plating jig according to claim 11, wherein the rotary means for the substrate holder is configured to transmit a rotational force to the shaft portion of the substrate holder or the outer frame member by a gear member from a drive part mounted on the support portion.

16. The plating jig according to claim 10, wherein the rotary means for the substrate holder is formed by combining a plurality of rotary means.

17. A plating device, wherein the plating jig according to claim 10 is engageable with a side wall of a plating bath, and a paddle which is movable in a reciprocating manner in a lateral direction is arranged between the substrate holder and an anode plate which is arranged to face the substrate holder in an opposed manner.

18. A plating device, wherein the plating jig according to claim 12 is engageable with a side wall of a plating bath, and a plating solution jetting port is formed in a bottom portion of the plating bath disposed below the substrate holder.