JP2000328297A - Substrate plating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate plating device which uniformly executes a plating treatment on a substrate and prevents the wiring defect between layers. SOLUTION: The substrate plating device for executing the plating treatment on the treatment surface WF of a wafer W has a holding mechanism 1 for holding the wafer W, an upper cup 10 for covering the wafer W held in this holding mechanism 1 from above, a supply port 24 for supplying an electrolytic plating liquid to the treatment surface WF of the wafer W held in the holding mechanism 1 and an air exit 25 for reducing the pressure in a plating treatment space 12 formed by the holding mechanism 1 and the upper cup 10 before the electrolytic plating liquid is supplied from the supply port 24 to the treatment surface WF of the wafer W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate plating apparatus for supplying a plating solution to a substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display, and a glass substrate for a photomask to perform a plating process on the substrate.

[0002]

2. Description of the Related Art In a process of manufacturing a semiconductor device, a plating solution is supplied to a processing surface of a wafer to form wiring on a processing surface of the wafer, which is a kind of substrate, and a plating layer is formed on the processing surface of the wafer. There is a plating process. Conventionally, the plating process includes a method of forming a plating layer on a processing surface of a wafer with the processing surface of the wafer facing upward, and a method of forming a plating layer on the processing surface of the wafer with the processing surface of the wafer facing downward. And a method of forming a plating layer on the treated surface.

[0003] First, in a method in which the processing surface of a wafer is directed upward, a plating solution is supplied from a plating solution supply nozzle to the processing surface of the wafer while the wafer is held by a holding mechanism while the wafer is directed upward. The plating layer is formed over the entire processing surface of the wafer. In the method in which the processing surface of the wafer faces downward, the processing surface of the wafer is immersed in a processing tank in which a plating solution is stored while the wafer is held by a holding mechanism with the processing surface of the wafer facing upward. The plating layer is formed over the entire processing surface of the wafer.

When the plating layer is formed, as shown in FIGS.
00 is formed as a first layer and an interlayer insulating film 201
Is formed as a second layer, and the interlayer insulating film 20
A concave portion, which is a step, is formed between the two. Therefore, in either case, the plating process is performed on the wafer W in such a state, and the plating layer 202 a is formed on the surface of the interlayer insulating film 201.

[0005]

However, any of the methods has the following problems.

First, in the case of the method in which the processing surface of the wafer W is directed upward, when the plating solution is supplied to perform the plating process, as shown in FIG.
Gets in. For this reason, when the plating layer 202b is formed on the surface of the interlayer insulating film 201, voids V are formed in the concave portions as shown in FIG. The yield will be worse.

In the case of the method in which the processing surface of the wafer W is directed downward, when the plating process is performed by immersing the wafer W in the processing tank, as shown in FIG. Air A enters the air. Therefore, the interlayer insulating film 2
When the plating layer 202b is formed on the surface of
As shown in FIG. 2B, voids V are formed in the concave portions, and as a result, as in the case of the method in which the processing surface of the wafer W is directed upward, the yield of the semiconductor device is deteriorated due to poor wiring between layers. That means that

The entry of the air A into the recesses and the formation of the voids V become more problematic as the aspect ratio of the interlayer insulating film 201 increases.

Therefore, before performing the plating process, the adhesive force of the air A that has entered the concave portion with respect to the lower wiring 200 and the interlayer insulating film 201 using an additive or the like is released, and the air A is taken out from the concave portion by buoyancy. Although it is conceivable that the air A does not flow out of the recess and remains in the recess.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a substrate plating apparatus for uniformly plating a substrate and preventing wiring failure between layers.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is a substrate plating apparatus for plating a substrate, comprising: a substrate holding means for holding a substrate; A cup covering the substrate from above, a plating solution supply means for supplying a plating solution to the processing surface of the substrate held by the substrate holding means, and a plating solution supplied by the plating solution supply means to the processing surface of the substrate, Decompression means for decompressing a space formed by the substrate holding means and the cup,
It is characterized by having.

The pressure reducing means may be provided with an exhaust means for exhausting gas in a space formed by the substrate holding means and the cup.

A positive electrode provided in a space formed by the substrate holding means and the cup and disposed above the processing surface of the substrate held by the substrate holding means and opposed to the processing surface of the substrate; The apparatus may further include a negative electrode electrically connected to the substrate held by the holding means, and a power supply means for supplying power so that a current flows between the positive electrode and the negative electrode. In this case, the plating solution is an electrolytic plating solution.

The apparatus may further include a chamber for accommodating the substrate holding means and the cup, and an inert gas supply means for supplying an inert gas into the chamber. In this case, it is conceivable that an inert gas such as N2 gas (nitrogen gas) is supplied into the chamber from the inert gas supply unit when the substrate is carried in with the substrate holding unit and the cup separated from each other. .

The plating solution supply means has a supply port formed at the top of the cup, and supplies the plating solution to the processing surface of the substrate held by the substrate holding means by supplying the plating solution into the cup. You may do it.

According to another aspect of the present invention, there is provided a substrate plating apparatus for plating a substrate, comprising: a substrate holding means for holding the substrate; a chamber for accommodating the substrate holding means; A plating solution supply unit that supplies a plating solution to the processing surface of the substrate held by the holding unit, and a pressure reducing unit that reduces the pressure in the chamber before supplying the plating solution to the processing surface of the substrate by the plating solution supply unit. It is characterized by having.

The pressure reducing means may be provided with an exhaust means for exhausting gas in the chamber.

A positive electrode provided in the chamber and disposed above the processing surface of the substrate held by the substrate holding means and opposed to the processing surface of the substrate; A negative electrode, which is electrically connected, and power supply means for supplying power so that current flows between the positive electrode and the negative electrode,
May be further provided. In this case, the plating solution is an electrolytic plating solution.

The plating solution supply means has a supply port formed in the upper part of the chamber, and supplies the plating solution to the processing surface of the substrate held by the substrate holding means by supplying the plating solution into the cup. You may do it.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS <First Embodiment> A first embodiment according to the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram of the substrate plating apparatus according to the first embodiment.

In this substrate plating apparatus, a wafer W, which is a kind of substrate, is oriented with a processing surface FW for forming a plating layer facing upward.
Is provided.

In the holding mechanism 1, a disk-shaped base member 4 having a diameter larger than that of the wafer W is integrally rotated on an upper part of a rotating shaft 3 which is connected to an electric motor 2 and is rotated around a vertical axis. At least three holding members 5 that are connected to each other and that hold the peripheral edge of the wafer W are provided around the upper surface of the base member 4. The holding member 5 can be provided continuously over the entire circumference.

The base member 4 is formed of a conductive material. A power supply brush 6 supplies power to the connecting portion 4 a of the base member 4 that connects to the rotating shaft 3 even during rotation of the holding mechanism 1. The upper and lower portions of the rotating shaft 3 are electrically insulated by an insulating portion 3a.
Is configured so as not to affect.

Each holding member 5 is configured to be rotatable around a vertical axis, and locks the wafer W on an outer peripheral portion away from the axis. In addition, in each holding member 5, only the negative electrode 7 provided on the ceiling surface is electrically connected to the power supply brush 6, and when the wafer W is locked and held by each holding member 5, the wafer W The processing surface WF of W and the negative electrode 7 are electrically connected to each other, and only the processing surface WF of the wafer W is energized. When the holding member 5 is provided on the entire circumference, the holding member 5 can be moved in the vertical direction. After the wafer W is set from between the holding member 5 and the base member 4 that have moved upward, the holding member 5 is lowered. As a result, the wafer W is locked.

The holding mechanism 1 is configured to be vertically movable by a first lifting mechanism 8. The first elevating mechanism 8 is realized by a well-known uniaxial driving mechanism including a ball screw or the like.

Above the holding mechanism 1, a lower part is opened,
An upper cup 10 that covers the upper part of the holding mechanism 1 and that has an inverted U-shape and a closed cylindrical shape is provided. The upper cup 10 corresponds to the cup of the present invention. This upper cup 1
0 is also configured to be able to move up and down in the vertical direction by a second lifting mechanism 11 realized by a well-known one-axis driving mechanism. The holding mechanism 1 and the upper cup 10 are brought close to each other by the first lifting mechanism 8 and the second lifting mechanism 11, and the upper surface of the base member 4 of the holding mechanism 1 and the lower end of the upper cup 10 are closed to each other. A plating processing space 12 for storing an electroplating solution is formed above the wafer W held by the substrate 1. An annular seal member 13 is provided at a lower end portion of the upper cup 10. When an electrolytic plating solution for performing a copper plating process is filled in the plating solution processing space 12, the upper surface of the base member 4 and the upper cup 10 are closed. The electrolytic plating solution is prevented from leaking from the joint with the lower end of the electroplating.

A disc-shaped positive electrode 14 is disposed in the upper cup 10 so as to be opposed to the processing surface WF of the wafer W held by the holding mechanism 1. This positive electrode 1
4 is attached to the ceiling side of the upper cup 10.

The power supply brush 6 is connected to the cathode side of the power supply unit 15, and the positive electrode 14 is connected to the anode side of the power supply unit 15. Therefore, the processing surface WF of the wafer W
In addition, only the negative electrode 7 becomes a cathode via a conductive part (not shown) for conducting with the base member 4, the base member 4, the connecting part 4 a, the power supply brush 6, and the conductor 16, and the positive electrode 14 via the conductor 17. Power is supplied so that it becomes an anode.

A supply port 24 and an exhaust port 25 for the electrolytic plating solution are formed in the ceiling of the upper cup 10.
From the supply port 24, an electrolytic plating solution is supplied to the plating space 12. From the exhaust port 25, the plating space 12
Is discharged, and the pressure of the plating processing space 12 is reduced by discharging the gas.

The electrolytic plating solution is supplied to the plating space 12 through the electrolytic plating solution supply port 24 formed in the ceiling portion of the upper cup 10 in the following manner.

That is, the supply port 24 is connected to the electrolytic plating solution supply source 30 via the supply pipe 31. An on-off valve 32 and a pump 33 are provided in the middle of the supply pipe 31. When supplying the electrolytic plating solution to the plating space 12 while the substrate plating apparatus is operating, the on-off valve 3
The pump 33 is constantly driven with 2 open.
When the electrolytic plating solution is not supplied to the plating space 12, the open / close valve 32 is switched from open to closed.

Further, the gas in the plating space 12 is exhausted from the exhaust port 25 formed in the ceiling portion of the upper cup 10 as described below, and the pressure in the plating space 12 is reduced. I have.

That is, the exhaust port 25 communicates with the outside of the substrate plating apparatus via the exhaust pipe 26. An on-off valve 27 is provided in the exhaust pipe 26. When the gas in the plating space 12 is discharged, the on-off valve 27
Is opened, gas is exhausted from the exhaust port 25, and the pressure in the plating space 12 is reduced.

The base member 4 and the upper cup 10 of the holding mechanism 1 are housed in a chamber 40. Chamber 40
In the ceiling part, a conductor hole 41 for the conductor 17 connecting the positive electrode 14 and the power supply unit, a supply tube hole 42 for the supply tube 31, and an exhaust tube hole 4 for the exhaust tube 26 are provided.
3 are formed respectively. Also, the chamber 40
An N2 gas supply port 44 connected to a N2 gas (nitrogen gas) supply source (not shown) via a supply pipe 50 provided with an on-off valve 51 in the middle is formed on one side of the. An unillustrated transfer port for transferring the wafer W into and out of the chamber 40 is provided on the side portion. When plating the wafer W in the chamber 40,
N2 gas is supplied into the chamber 40 from the N2 supply port 44, and the inside of the chamber 40 is set to an atmosphere of N2 gas.

Around the holding mechanism 1 in the chamber 40,
An electrolytic plating solution recovery section 45 is formed. A cylindrical outer wall 47 is provided around the outer periphery of the recovery port 46 of the electrolytic plating solution recovery section 45.
However, a cylindrical inner wall 48 is provided on the inner periphery of the collection port 46.

During the electroplating process, the holding mechanism 1 is moved up and down with respect to the electrolytic plating solution collecting section 45 by the first elevating mechanism 8 so that the collecting port 46 of the electrolytic plating solution collecting section 45 is positioned around the holding mechanism 1. The electrolytic plating solution scattered around the holding mechanism 1 and the wafer W with the rotation of the holding mechanism 1 and the wafer W held by the holding mechanism 1 is collected by the liquid collecting unit 4.
5 is collected in the recovery port 46. The electrolytic plating solution recovered in the recovery port 46 is discarded to the outside of the substrate plating apparatus via a liquid discharge port 49 formed at the bottom of the chamber 40 and a discharge pipe 52. An opening / closing valve 61 for adjusting the discharge of the electrolytic plating solution is provided in the middle of the discharge pipe 52.

Next, the operation of the substrate plating apparatus according to the first embodiment will be described. FIG. 2 is a flowchart showing the operation of the substrate plating apparatus according to the first embodiment.

First, the supply of the N2 gas into the chamber 40 is started by opening the on-off valve 51 (step S).
1). Next, the wafer W with the processing surface WF facing upward is held by the holding mechanism 1 through the loading / unloading port provided on the side of the chamber 40 (step S2).

More specifically, the holding mechanism 1 is raised by the first lifting / lowering mechanism 8 so that the base member 4 of the holding mechanism 1 is positioned above the recovery port 46 of the electrolytic plating solution recovery section 45 and the second The upper cup 1 by the lifting mechanism 11
0 is raised to separate the holding mechanism 1 from the upper cup 10 so that a transfer arm (not shown) can enter. In addition, each holding member 5 is rotated so that the locking portion of each holding member 5 faces outward, so that the wafer W can be received.

Further, the transfer arm is advanced with the processing surface WF of the wafer W facing upward, and the height of the peripheral edge of the wafer W is adjusted to the height corresponding to the height of the locking portion of each holding member 5. To Then, by rotating each holding member 5, the peripheral portion of the wafer W is locked by the locking portion of each holding member 5, and the wafer W
And the transfer arm is retracted from the chamber 40.

When the holding of the wafer W on the holding mechanism 1 is completed, the holding mechanism 1 is lowered by the first lifting / lowering mechanism 8, and around the base member 4 of the holding mechanism 1, the electrolytic plating solution collecting section 45 is moved. The recovery port 46 is located and the second
The upper cup 10 is lowered by the elevating mechanism 11 to bring the holding mechanism 1 and the upper cup 10 close to each other. Thereby, the upper surface of the base member 4 of the holding mechanism 1 and the upper cup 10
Are closed with each other to form a plating space 12.

Next, the on-off valve 51 is switched from open to closed, and the supply of N2 gas into the chamber 40 is stopped (step S3). Thus, the inside of the chamber 40 is filled with the N2 gas atmosphere.

Next, the on-off valve 27 is switched from closed to open, and the gas in the plating space 12 is exhausted to reduce the pressure in the plating space 12 (step S4). After a lapse of a predetermined time, the opening / closing valve 27 is switched from open to closed, and the pressure reduction processing of the plating processing space 12 ends. As shown in FIG. 4A, the surface of the wafer W at this time is such that an underline wiring 200 is formed as a first layer on the surface of the wafer W, and an interlayer insulating film 201 is formed thereon as a second layer. In this state, a concave portion is formed between the interlayer insulating films 201. However, unlike the conventional technique shown in FIGS. 8A and 9A, air enters the concave portion. Not.

When the decompression process of the plating space 12 in step S4 is completed, an electrolytic plating solution is supplied to the plating space 12, and the plating process is performed on the processing surface WF of the wafer W as shown in FIG. 3 (step S5). ). FIG.
5 is a flowchart showing an operation of a plating process.

First, the open / close valve 32 is opened, and the supply of the electrolytic plating solution from the electrolytic plating solution supply source 30 via the supply pipe 31 and the supply port 24 is started (step S51).
Thus, the electrolytic plating solution is supplied to the plating space 12, and after a predetermined time has elapsed, the plating space 12 is filled with the electrolytic plating solution. At this time, as shown in FIG. 4B, the upper surface of the interlayer insulating film 201 is filled with the electrolytic plating solution 202a, and the electrolytic plating solution 202a enters the concave portion.

Next, while the supply of the electrolytic plating solution to the plating processing space 12 is continued, the upper cup 10 is lifted by the second lifting mechanism 11 to hold the holding mechanism 1 and the upper cup 1.
0 is separated by a predetermined amount (step S52), and a gap for discharging the electrolytic plating solution is formed around the wafer W held by the holding mechanism 1. Along with this, while the electric motor 2 is driven to rotate the holding mechanism 1 and the wafer W held by the holding mechanism 1 (step S53), the power supply unit 15 is operated to cause the gap between the positive electrode 14 and the negative electrode 7 to move. Is supplied (step S54).

As a result, the processing surface WF of the wafer W becomes a cathode (-) and the positive electrode 14 becomes an anode (+), and the electrode plating filled between the processing surface WF of the wafer W and the positive electrode 14 is performed. When the solution is electrolyzed and, for example, the electrolytic plating solution is a copper sulfate plating solution, as shown in FIG. 4C, the plating layer 202b is formed on the upper surface of the interlayer insulating film 201, and the plating layer 202b is formed in the concave portion. Also, a plating layer 202b is formed.

The electrolytic plating solution scattered around from the gap with the rotation of the holding mechanism 1 and the wafer W is collected in the collecting port 46 of the electrolytic plating solution collecting section 45, and the liquid discharging port 49.
Is discharged out of the substrate plating apparatus through the

When the power supply process in step S54 is completed,
The on-off valve 32 is switched from open to closed to stop the supply of the electrolytic plating solution from the supply port 24 to the plating processing space 12 (step S55), and the driving of the electric motor 2 is stopped to rotate the holding mechanism 1. Stop temporarily (step S5
6). Then, the upper cup 1 is driven by the second lifting drive 11.
0 is further raised, the distance between the holding mechanism 1 and the upper cup 10 is further increased, and the electrolytic plating solution in the plating space 12 is discharged to the recovery port 46 of the electrolytic plating solution recovery unit 45 (Step S57). Thus, a series of plating processes in step S5 is completed.

When the plating process in step S5 is completed,
While rotating the wafer W by the electric motor 2, a cleaning liquid is supplied from a cleaning liquid supply nozzle (not shown) to the processing surface WF of the wafer W to perform a cleaning process (step S6). When the cleaning processing is performed for a predetermined time, the supply of the cleaning liquid from the cleaning liquid supply nozzle to the processing surface WF of the wafer W is stopped.

After the cleaning process at step S6, the wafer W is rotated at a higher speed by the electric motor 2, and the cleaning liquid adhering to the processing surface WF of the wafer W is shaken off and dried (step S7). The cleaning liquid scattered around from the gap with the rotation of the holding mechanism 1 and the wafer W is collected by the liquid recovery unit 45.
And is discharged out of the substrate plating apparatus through a liquid discharge port 49. When the drying process in step S7 is performed for a predetermined time, the driving of the electric motor 2 is stopped and the rotation of the holding mechanism 1 is stopped.

Thereafter, the wafer W is unloaded from the holding mechanism 1 (Step S8).

Specifically, the holding mechanism 1 is raised by the first lifting mechanism 8, and the base member 4 of the holding mechanism 1 is positioned above the recovery port 46 of the liquid recovery section 45. next,
The transfer arm is moved into the chamber 40 to support the wafer W held by the holding member 5 and rotate each holding member 5 so that the locking portion of each holding member 5 faces outward. The holding is released, and the wafer W is delivered to the transfer arm. Then, the transfer arm supporting the wafer W is retracted, and the wafer W is unloaded from the chamber 40.

Thus, a series of operations of the substrate plating apparatus according to the first embodiment ends.

As is clear from the above configuration and operation,
According to the first embodiment of the present invention, the following effects can be obtained.

That is, the gas in the plating space 12 is evacuated by opening the on-off valve 27 and the pressure in the plating space 12 is reduced. After that, the electrolytic plating solution is supplied to the plating space 12 and the wafer W Is performed, when the plating layer 202b is formed on the surface of the interlayer insulating film 201, no void is formed in the concave portion. As a result, the yield of the semiconductor device can be prevented due to a wiring failure between layers.

The decompression process in the plating space 12 is as follows:
Since the gas in the plating space 12 is exhausted from the exhaust port 25 communicating with the outside of the substrate plating apparatus through the exhaust pipe 26 by controlling the opening and closing of the on-off valve 27, the pressure in the plating space 12 is reduced by a simple configuration. Can be realized.

Since the electrolytic plating is performed while rotating the holding mechanism 1 and the wafer W held by the holding mechanism 1, the rotation of the wafer W causes the center of the wafer W on the processing surface WF of the wafer W to move from the center to the periphery. The flow of the electroplating solution is formed, and the boundary layer formed on the processing surface WF of the wafer W held by the holding mechanism 1 can be made thin and uniform, and the plating layer is formed on the processing surface WF of the wafer W. The formation ions are easily moved, and the movement of the plating layer formation ions to the processing surface WF of the wafer W can be made uniform. Therefore, the time required for forming the plating layer can be reduced, and a uniform plating layer can be formed on the processing surface WF of the wafer W.

Further, since the electrolytic plating solution around the positive electrode 14 is held in the upper cup 10, the state where the positive electrode 14 is immersed in the electrolytic plating solution can be always maintained. Therefore, the positive electrode 14 can be prevented from being exposed to the atmosphere, and the plating layer formed on the surface of the positive electrode 14 can be prevented from flowing or being deteriorated.
A reproducible electrolytic plating process can be performed.

Further, when the wafer W is loaded and held, the on-off valve 51 is opened to supply the N2 gas, which is an inert gas, into the chamber 40. Therefore, the wafer W is kept clean. Can be performed. Further, since the plating process can be performed in an atmosphere of N2 gas, the oxidative decomposition of additives in the electrolytic plating solution by air in the atmosphere can be prevented, and the life of the electrolytic plating solution can be extended.

<Second Embodiment> A second embodiment according to the present invention will be described below with reference to the drawings. FIG.
It is a schematic structure figure of a substrate plating device concerning a 2nd embodiment.

In this substrate plating apparatus, a wafer W, which is a kind of substrate, is oriented with a processing surface FW for forming a plating layer facing upward.
Is provided.

The holding mechanism 61 is connected to an electric motor 62 and is connected to a rotating shaft 6 which is rotated about a vertical axis.
A disk-shaped base member 6 having a diameter larger than that of the wafer W
4 are connected so as to be integrally rotatable, and three or more holding members 65 for holding the peripheral portion of the wafer W are provided around the upper surface of the base member 64. The holding member 55 can be provided continuously over the entire circumference.

The base member 64 is formed of a conductive material. A power supply brush 66 supplies power to the connecting portion 64 a of the base member 64 that is connected to the rotating shaft 63 while the holding mechanism 61 is rotating. The upper and lower portions of the rotating shaft 63 are electrically insulated by an insulating portion 63a, and are configured so that power supply from the power supply brush 66 does not affect the electric motor 62.

Each holding member 65 is configured to be rotatable around a vertical axis, and locks the wafer W on an outer peripheral portion away from the axis. Further, each holding member 65 is configured such that only the negative electrode 67 (not shown) provided on the ceiling surface side is a power supply brush 66.
The wafer W is connected to each holding member 6.
5, the processing surface WF of the wafer W is electrically connected to the negative electrode 67, and the processing surface W of the wafer W is electrically connected.
Only the F is energized. When the holding member 55 is provided on the entire circumference, the holding member 55 can be moved in the vertical direction, and the holding member 55 and the base member 54 that have moved upward.
After setting the wafer W from between the above, the holding member 5 is lowered to lock the wafer W.

The holding mechanism 61 is configured to be vertically movable by a first lifting mechanism 68. The first elevating mechanism 68 is realized by a well-known one-axis driving mechanism including a ball screw or the like.

This holding mechanism 61 is housed in a chamber 70. This chamber 70 has a lower chamber 701 having an upper opening and an upper chamber 70 having a lower opening.
The upper chamber 702 is configured to be able to move up and down with respect to the lower chamber 701 by a second elevating mechanism 80 realized by a well-known uniaxial driving mechanism. Also, the upper end of the lower chamber 701 and the lower end of the upper chamber 702 respectively
1, 712 are provided to prevent leakage of gas from the plating space 81 formed by the lower chamber 701 and the upper chamber 702 by joining the seal members 711, 712.

The upper chamber 70 in the chamber 70
A cylindrical support member 71 is provided on a ceiling portion of the disk drive 2, and a disc-shaped positive electrode is disposed in the support member 71 so as to face the processing surface WF of the wafer W held by the holding mechanism 61. 72 are provided. The positive electrode 72 has a plurality of holes 73 through which the electrolytic plating solution passes.

The power supply brush 66 is connected to the cathode side of the power supply unit 77, and the positive electrode 72 is connected to the anode side of the power supply unit 77. Therefore, the processing surface W of the wafer W
F is a cathode through a conductive portion (not shown) that allows only the negative electrode 67 to be in conduction with the base member 64, the base member 64, the connecting portion 64 a, the power supply brush 66, and the conducting wire 78, and the positive electrode 7.
2 is supplied as an anode through a conductive wire 79 passing through the inside of the support member 71.

Further, a supply port 703 and an exhaust port 704 for the electrolytic plating solution are formed in the ceiling portion of the upper chamber 702. From the supply port 703, an electrolytic plating solution is supplied to the plating space 81. The gas in the plating space 81 is exhausted from the exhaust port 704, and the pressure in the plating space 81 is reduced.

The electrolytic plating solution is supplied to the plating space 81 through the electrolytic plating solution supply port 703 formed in the ceiling portion of the upper chamber 702 as follows.

That is, the supply port 703 is connected to the electrolytic plating solution supply source 91 via the supply pipe 90. An on-off valve 92 and a pump 93 are provided in the middle of the supply pipe 90. When supplying the electrolytic plating solution to the plating processing space 81 during operation of the substrate plating apparatus, the on-off valve 92 is opened and the pump 93 is constantly driven. When the electrolytic plating solution is not supplied to the plating space 81, the open / close valve 92 is switched from open to closed.

The gas in the plating space 81 is discharged from the exhaust port 704 formed in the ceiling of the upper chamber 702 as follows.
Is decompressed.

That is, the exhaust port 704 is
Through the substrate plating apparatus. Exhaust pipe 1
In the middle of 00, an on-off valve 101 is provided. When the gas in the plating space 81 is discharged, the on-off valve 101 is opened to discharge the gas from the exhaust port 704, and the pressure in the plating space 81 is reduced.

An N 2 gas supply port 705 connected to an N 2 gas supply source (not shown) through the supply pipe 102 is formed on one side of the upper chamber 702, and the wafer W is plated in the chamber 70. When processing, N2
N2 gas is supplied into the chamber 70 from the supply port 705,
The inside of the chamber 70 is set to an atmosphere of N2 gas. In the middle of the supply pipe 102, an on-off valve 103 for adjusting the supply of N2 gas is provided.

A liquid collecting section 82 is formed around the holding mechanism 61 in the chamber 70. A cylindrical outer wall 84 is provided on the outer circumference of the recovery port 83 of the liquid recovery section, and a cylindrical inner wall 85 is provided on the inner circumference of the recovery port 83.

At the time of the electrolytic plating process, the holding mechanism 68 is moved up and down by the first elevating mechanism 68 with respect to the liquid collecting section 82 so that the collecting port 83 of the liquid collecting section 82 is positioned around the holding mechanism 68. With the rotation of the wafer W held by the holding mechanism 68 and the holding mechanism 68, the electrolytic plating solution scattered around the holding mechanism 68 and the wafer W is stored in the recovery port 83 of the liquid recovery unit 82. The electrolytic plating solution recovered in the recovery port 83 is discarded outside the substrate plating apparatus via a liquid discharge port 706 formed in the bottom of the lower chamber 701 and the discharge pipe 104. An opening / closing valve 105 for adjusting the discharge of the electrolytic plating solution is provided in the middle of the discharge pipe 104.

Next, the operation of the substrate plating apparatus according to the second embodiment will be described. FIG. 6 is a flowchart showing the operation of the substrate plating apparatus according to the second embodiment.

First, the supply of the N 2 gas into the chamber 70 is started by opening the on-off valve 92 (step T).
1). Next, the holding mechanism 61 holds the wafer W with the processing surface WF facing upward (step T2).

Specifically, the upper chamber 702 is raised by the second lifting mechanism 80 to separate the upper chamber 702 from the lower chamber 701, and the base member 64 of the holding mechanism 61 is moved by the first lifting mechanism 68. The transfer arm (not shown) is positioned above the collection port 83 of the collection section 82 so that it can enter the chamber 70. In addition, each holding member 65 is rotated so that the locking portion of each holding member 65 faces outward, so that the wafer W can be received.

The transfer arm is advanced with the processing surface WF of the wafer W directed upward, and the height of the peripheral edge of the wafer W is adjusted to the height corresponding to the height of the locking portion of each holding member 65. To Then, each holding member 65 is rotated, the peripheral edge of the wafer W is locked by the locking portion of each holding member 65 to hold the wafer W, and the transfer arm is evacuated from the chamber 70.

When the holding of the wafer W on the holding mechanism 61 is completed, the holding mechanism 61 is lowered by the first lifting / lowering mechanism 68 so that the periphery of the base member 64 of the holding mechanism 61 is removed.
The recovery port 83 of the liquid recovery section 82 is located and the second
The upper chamber 702 is lowered by the elevating mechanism 80 so that the seal member 711 and the seal member 712 are joined. As a result, the plating processing space 81 in the chamber 70 is formed.
Is formed.

Next, the on / off valve 92 is switched from open to closed, and the supply of N2 gas into the chamber 70 is stopped (step T3). Thus, the inside of the chamber 70 is filled with the N2 gas atmosphere.

Next, the on-off valve 101 is switched from the closed state to the open state to exhaust the processing gas in the plating processing space 81, in particular, the space in the support member 71, and depressurize the plating processing space 81 (step T4). After a predetermined time has passed, the on-off valve 10
1 is switched from open to closed, and the decompression process of the plating process space 81 ends. The processing surface of the wafer W at this time is as follows:
As in the case of the first embodiment, as shown in FIG. 4A, a lower wiring 200 is formed as a first layer on a processing surface of a wafer W, and an interlayer insulating film 201 is formed thereon as a second layer. Although a concave portion is formed between the interlayer insulating films 201, unlike the conventional technology shown in FIGS. 8A and 9A, air is filled in the concave portion. I have not entered.

When the pressure reduction in the plating space 81 in step T4 is completed, an electrolytic plating solution is supplied to the plating space 81, and the plating process is performed on the processing surface WF of the wafer W as shown in FIG. 7 (step T5). ). FIG.
5 is a flowchart showing an operation of a plating process.

First, the on-off valve 93 is opened, and the supply of the electrolytic plating solution from the electrolytic plating solution supply source 91 through the supply pipe 90 and the supply port 703 is started (step T5).
1). Thereby, the support member 71 of the plating space 81 is
When a predetermined time elapses after the electrolytic plating solution is supplied to the space, the space in the support member 71 is filled with the electrolytic plating solution. At this time, the electrolytic plating solution enters the space below the positive electrode 72 from the space above the positive electrode 72 through the plurality of holes 73 and is supplied to the processing surface WF of the wafer W. The processing surface of the wafer W at this time is shown in FIG.
As shown in FIG. 7, the upper surface of the interlayer insulating film 201 is filled with the electrolytic plating solution 202a, and the electrolytic plating solution enters the recess. After that, N2 gas may be supplied for a predetermined time to return the inside of the chamber 70 to the atmospheric pressure.

Next, the supply of the electrolytic plating solution to the plating processing space 81 is continued, and the electric motor 62 is driven to rotate the holding mechanism 61 and the wafer W held by the holding mechanism 61 (step T52). The power supply unit 67 is operated to supply power between the positive electrode 72 and the negative electrode 67 (step T53).

As a result, the processing surface WF of the wafer W becomes the cathode (-) and the positive electrode 72 becomes the anode (+), and the electrode plating filled between the processing surface WF of the wafer W and the positive electrode 72 is performed. When the solution is electrolyzed and, for example, the electrolytic plating solution is a copper sulfate plating solution, as shown in FIG. 4C, the plating layer 202b is formed on the upper surface of the interlayer insulating film 201, and the plating layer 202b is formed in the concave portion. Also, a plating layer 202b is formed.

The electrolytic plating solution scattered around from the gap with the rotation of the holding mechanism 61 and the wafer W is collected in the collecting port 83 of the liquid collecting section 82, and is collected outside the substrate plating apparatus through the liquid discharging port 706. Is discharged.

When the power supply process in step T53 is completed,
The on / off valve 92 is switched from open to closed to stop the supply of the electrolytic plating solution from the supply port 703 to the plating processing space 81 (step T54), and the driving of the electric motor 62 is stopped to rotate the holding mechanism 61. The operation temporarily stops (step T55). The electrolytic plating solution is discharged to a recovery port 83 of the liquid recovery section 82. Thus, a series of plating processes in Step T5 is completed.

When the plating process in step T5 is completed,
While the wafer W is rotated by the electric motor 62, a cleaning liquid is supplied from a cleaning liquid supply nozzle (not shown) to the processing surface WF of the wafer W to perform a cleaning process (step T6). When the cleaning processing is performed for a predetermined time, the supply of the cleaning liquid from the cleaning liquid supply nozzle to the processing surface WF of the wafer W is stopped.

After the cleaning process in step T6, the wafer W is further rotated at a higher speed by the electric motor 62, and the cleaning liquid adhering to the processing surface WF of the wafer W is shaken off to dry the wafer W (step T7). The cleaning liquid scattered from the gap to the surroundings with the rotation of the holding mechanism 61 and the wafer W is recovered by the recovery port 83 of the liquid recovery section 82 and the liquid discharge port 70
6 and is discharged out of the substrate plating apparatus. When the drying process in step T7 is performed for a predetermined time, the driving of the electric motor 62 is stopped, and the rotation of the holding mechanism 61 is stopped.

Thereafter, the wafer W is carried out of the holding mechanism 61 (Step T8).

Specifically, the upper chamber 702 is raised by the second raising / lowering mechanism 80, and the holding mechanism 61 is raised by the first raising / lowering mechanism 68.
Is positioned above the recovery port 63 of the liquid recovery section 62. Next, the transfer arm is advanced into the chamber 70 to support the wafer W held by the holding member 65 and rotate each holding member 65 so that the locking portion of each holding member 65 faces outward. The holding of the wafer W is released, and the wafer W is delivered to the transfer arm. Then, the transfer arm supporting the wafer W is retracted, and the wafer W is unloaded from the chamber 70.

Thus, a series of operations of the substrate plating apparatus according to the second embodiment ends.

As is clear from the above configuration and operation,
According to the second embodiment of the present invention, the following effects can be obtained.

That is, the gas in the plating space 81 is exhausted by opening the on-off valve 101 and the pressure in the plating space 81 is reduced.
1 is supplied with an electrolytic plating solution to perform a plating process on the wafer W, so that the plating layer 20 is formed on the surface of the interlayer insulating film 201.
When 2b is formed, no void is formed in the concave portion. As a result, the yield of the semiconductor device can be prevented due to a wiring failure between layers.

The pressure reduction in the plating space 81 is as follows.
Since the gas in the plating space 81 is exhausted from the exhaust port 704 communicating with the outside of the substrate plating apparatus through the exhaust pipe 100 by controlling the opening and closing of the on-off valve 101, the pressure in the plating space 81 is reduced with a simple configuration. Can be realized.

Since the electrolytic plating is performed while rotating the holding mechanism 61 and the wafer W held by the holding mechanism 61, the rotation of the wafer W causes the center of the wafer W on the processing surface WF of the wafer W to move from the center to the periphery. The flow of the electrolytic plating solution is formed, and the boundary layer formed on the processing surface WF of the wafer W held by the holding mechanism 61 can be thin and uniform, and the plating layer is formed on the processing surface WF of the wafer W. The formation ions are easily moved, and the movement of the plating layer formation ions to the processing surface WF of the wafer W can be made uniform. Therefore, the time required for forming the plating layer can be reduced, and a uniform plating layer can be formed on the processing surface WF of the wafer W.

[0100]

As described above in detail, according to the present invention, before the plating liquid is supplied to the processing surface of the substrate by the plating liquid supply means, the space formed by the substrate holding means and the cup is reduced. As a result, the plating process on the substrate can be performed uniformly, and a wiring failure between layers of the semiconductor device can be prevented.

According to the present invention, since the pressure in the chamber is reduced by the pressure reducing means before the plating liquid is supplied to the processing surface of the substrate by the plating liquid supply means, the plating processing on the substrate can be performed uniformly. In addition, wiring defects between layers of the semiconductor device can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a substrate plating apparatus according to a first embodiment.

FIG. 2 is a flowchart showing an operation of the substrate plating apparatus according to the first embodiment.

FIG. 3 is a flowchart showing an operation of a plating process of the substrate plating apparatus according to the first embodiment.

FIG. 4 is a diagram illustrating a process of forming a plating layer on a processing surface of a wafer.

FIG. 5 is a schematic configuration diagram of a substrate plating apparatus according to a second embodiment.

FIG. 6 is a flowchart showing an operation of the substrate plating apparatus according to the second embodiment.

FIG. 7 is a flowchart showing an operation of a plating process of the substrate plating apparatus according to the second embodiment.

FIG. 8 is a diagram illustrating a problem of the conventional technique.

FIG. 9 is a diagram illustrating a problem of the conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holding mechanism 4 Base member 5 Holding member 6 Power supply brush 7 Negative electrode 10 Upper cup 12 Plating processing space 14 Positive electrode 15 Power supply unit 30 Plating liquid supply source 31 Supply pipe 31 33 Pump 40 Chamber 44 N2 gas supply port 50 Supply pipe 61 Holding mechanism 64 Base member 65 Holding member 66 Power supply brush 67 Negative electrode 70 Chamber 71 Plating space 72 Positive electrode 77 Power supply unit 90 Supply pipe 91 Electrolytic plating solution supply source 93 Pump 102 Supply pipe 703 Supply port 705 N2 gas supply port

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C25D 21/10 302 C25D 21/10 302 21/11 21/11 H01L 21/768 H01L 21/90 Q

Claims (7)

[Claims] 1. A substrate plating apparatus that performs a plating process on a substrate, comprising: a substrate holding unit that holds the substrate; a cup that covers the substrate held by the substrate holding unit from above; A plating solution supply unit for supplying a plating solution to the processing surface of the substrate, and a space formed by the substrate holding unit and the cup before the plating solution is supplied to the processing surface of the substrate by the plating solution supply unit. A substrate plating apparatus, comprising: 2. The substrate plating apparatus according to claim 1, wherein said decompression means includes an exhaust means for exhausting gas in said space. 3. The substrate plating apparatus according to claim 1, wherein the substrate plating apparatus is provided in the space and faces the processing surface of the substrate above the processing surface of the substrate held by the substrate holding means. A positive electrode that is disposed as follows; a negative electrode that is electrically connected to a substrate held by the substrate holding unit; and a power supply unit that supplies power so that a current flows between the positive electrode and the negative electrode. , A substrate plating apparatus. 4. The substrate plating apparatus according to claim 1, wherein a chamber accommodating said substrate holding means and said cup, and an inert gas for supplying an inert gas into said chamber. A substrate plating apparatus, further comprising: gas supply means. 5. A substrate plating apparatus for performing plating on a substrate, comprising: a substrate holding means for holding the substrate; a chamber for accommodating the substrate holding means; and a processing surface of the substrate held by the substrate holding means. A plating solution supply means for supplying a plating solution; and a pressure reducing means for reducing the pressure in the chamber before supplying the plating solution to the processing surface of the substrate by the plating solution supply means. apparatus. 6. A substrate plating apparatus according to claim 5, wherein said decompression means includes an exhaust means for exhausting gas in said chamber. 7. The substrate plating apparatus according to claim 5, wherein the substrate plating apparatus is provided in the chamber and faces the processing surface of the substrate above the processing surface of the substrate held by the substrate holding means. A positive electrode that is disposed as follows; a negative electrode that is electrically connected to a substrate held by the substrate holding unit; and a power supply unit that supplies power so that a current flows between the positive electrode and the negative electrode. , A substrate plating apparatus.