JP2002249896A - Liquid treating apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid treating apparatus which ensures the electrical contact which supplies electricity and surely seals the electrical contact from the treating liquid, and to provide the liquid treating method. SOLUTION: The sealing state of peripheral part of the object to be treated which is in electrical contact with a contact member which is disposed on a part holding the object to be treated is maintained until the part holding the object to be treated is retreated from the upper part of the treating vessel by a transporting mechanism. After the treatment, the treated surface of the object to be treated is washed. Therefore, without regarding the contamination of the washing liquid to the treating liquid, the treated surface and the part holding the body to be treated can be adequately washed by a washing mechanism which is different from the treating vessel. In addition, the washing mechanism can be disposed on a place different from the treating vessel and, thereby, an atmosphere in which the washing is performed is easily made to be a space in which there is no mist of treating liquid. As a result, even when the sealing state is opened, the contamination to the contact member and the sealing member which are disposed on the part holding the object to be treated is extremely reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid processing apparatus and a liquid processing method for performing liquid phase processing on an object to be processed, and more particularly, to an electric contact for supplying electricity to an object to be processed for liquid phase processing. The present invention relates to a liquid processing apparatus and a liquid processing method suitable for ensuring contact and for reliably sealing the electrical contact from a processing liquid.

[0002]

2. Description of the Related Art In recent years, a liquid processing step in a semiconductor manufacturing process or a liquid crystal device manufacturing process has been replaced by a reaction process in a gaseous phase due to the miniaturization of processing required for manufacturing a semiconductor device or a liquid crystal device. It is becoming increasingly used.

[0003] As an example of the liquid processing step, a step of applying copper plating to a wafer surface as an object to be processed will be described. When copper plating is performed on the surface of the wafer to be processed, a conductive seed layer serving as a cathode for electroplating and serving as a seed for plating is formed on the surface in advance.

[0004] The surface of the wafer to be processed on which the seeding layer is formed is
For example, it is immersed in a plating solution tank so as to come into contact with a plating solution based on copper sulfate, and from a plurality of points on the outer periphery of the wafer,
An electric conductor (cathode contact; hereinafter, simply referred to as a contact, as appropriate) is brought into contact with the seeding layer, and electricity for electrolytic plating is supplied.

Further, a contact portion of the peripheral portion of the wafer with the contact is sealed with a sealing member made of rubber, for example, so as to prevent the plating solution from entering. This prevents the contact from being corroded by the plating solution. The plating solution tank is provided with a copper anode electrode immersed in the plating solution and containing, for example, phosphorus.

By using these structures and supplying electricity between the cathode and the anode, copper is reduced and deposited on the cathode, which was initially the seeding layer, and copper is formed as plating on the seeding layer.

In the plating apparatus having the above-described structure, it is an important technical problem to ensure the electrical contact with the peripheral portion of the wafer by the cathode contact and to secure the sealing property of the cathode contact by the sealing member. It is.

If the electrical contact of the cathode contact with the peripheral portion of the wafer is not reliable, the electrical resistance of the contact increases, the uniformity of the plating film thickness on the wafer surface deteriorates, and the yield is affected. The increase in the contact resistance leads to the deterioration of the uniformity of the plating film thickness because the larger the contact resistance of the cathode contact, the smaller the flow of electricity during the plating process. This is because the amount of plating formed on the wafer surface also decreases.

Such deterioration of the electrical contact is caused not only by mechanical deterioration such as abrasion, but also by deterioration of the contact surface by a plating solution. As described above, the fact that the plating solution is corrosive is the cause of such deterioration. Therefore, it is important to ensure the sealing property of the cathode contact by the sealing member.

[0010] However, even if the sealing property is ensured during the plating process, there is a problem when the sealed state between the sealing member and the wafer is released when the wafer after the plating process is carried out of the plating solution tank. That is, since the residual plating solution present at the contact portion of the seal member forms a liquid film due to surface tension as the seal member is separated from the wafer, the liquid film is broken and splashes are scattered in the air. Since the droplets can adhere to the contacts located in the immediate vicinity, the corrosion of the contacts may be deteriorated depending on the residual amount of the plating solution component.

In the same case, if the plating solution remains on the surface of the seal member, the deposit acts as a non-elastic body on the surface of the seal member, which may cause poor sealing. Such poor sealing causes plating solution to enter the contact and causes a change in contact resistance of the contact.

Considering such circumstances, the following is a tentative measure for preventing the plating solution from being contaminated in the contact and the seal member. For example, there is a method in which a wafer processing surface is cleaned with pure water or the like in a plating apparatus before the sealing state of the wafer is released.

[0013]

According to the above method, the plating solution component contained in the droplets generated when the sealing state is broken is very small, and the plating solution contamination of the contact and the seal member is reduced. However, since the cleaning is performed in the plating apparatus, the cleaning solution is mixed into the plating solution tank, and is not appropriate for controlling the composition of the plating solution. Therefore, such cleaning cannot be performed very carefully.

In order to eliminate this inconvenience, a method is conceivable in which the above-mentioned cleaning is performed in the plating apparatus after all the plating solution is drained from the plating solution tank. According to this, the processing target wafer surface can be sufficiently cleaned,
Since it is necessary to drain the plating solution from the plating solution tank and refill it after cleaning for each single wafer processing, the productivity is extremely deteriorated and is not practical.

In the first place, when cleaning a wafer to be processed in a plating apparatus, the cleaning effect is limited to a certain extent because the cleaning is performed in an atmosphere in which mist of a plating solution is present.

As described above, the current plating apparatus has a configuration in which a failure in electrical contact with the peripheral portion of the wafer by the cathode contact and a failure in ensuring the sealing performance of the cathode contact by the sealing member can still occur. is there.

The present invention has been made in view of the above-mentioned circumstances, and ensures a contact of an electric contact for supplying electricity to an object to be processed for a liquid phase treatment, and also enables the electric contact to be removed from a processing liquid. It is an object of the present invention to provide a liquid processing apparatus and a liquid processing method capable of reliably sealing.

[0018]

In order to solve the above-mentioned problems, a liquid processing apparatus according to the present invention includes a first electrode capable of storing a processing liquid and being immersed in the stored processing liquid. A processing tank to be processed, a processing object holding unit for holding the processing object and bringing the processing surface into contact with the processing liquid, and the processing surface provided in the processing object holding unit and contacting the processing liquid A contact member electrically contacting a peripheral portion of the object to be processed so that the conductive layer becomes a second electrode; and a peripheral portion of the object provided in the object holding portion and electrically contacted. A sealing member that seals from the processing liquid that comes into contact with the processing surface, and the processing object holding portion that holds the processing object, the sealed processing object peripheral edge portion remains in a sealed state, An object to be withdrawn from the processing tank and moved to the processing tank And a cleaning mechanism for cleaning the retracted workpiece holding section including the processing surface of the workpiece held therein. ).

That is, the sealing state of the peripheral portion of the object to be electrically contacted with the contact member provided in the object holding portion is maintained until the object holding portion is retracted from the processing tank by the transfer mechanism. Is done. After retreating the object-to-be-processed holding part from above the processing tank, it is cleaned including the processing surface of the object to be processed.

Therefore, the processing surface and the object-to-be-processed holding portion can be sufficiently cleaned by a cleaning mechanism different from that of the processing tank without worrying about mixing of the cleaning liquid into the processing liquid. In addition, since this cleaning mechanism can be installed in a place different from the processing tank, it is easy to set the cleaning atmosphere to a space in which the processing liquid mist does not exist. Therefore, the cleaning effect of removing the plating solution component on the processing surface and the workpiece holding portion is sufficiently exhibited.

Thus, contamination of the contact member and the seal member provided on the processing object holding portion is greatly reduced even when the sealed state is opened. Therefore, it is possible to ensure the contact of the electric contact for supplying electricity to the object to be processed for the liquid phase treatment, and to reliably seal the electric contact from the processing liquid.

Further, in the liquid processing method according to the present invention, a processing tank having a first electrode capable of storing a processing liquid and being immersed in the stored processing liquid, and a processing object are held. An object-to-be-processed holding part for bringing the processing surface into contact with the processing liquid; and a second electrode provided on the object-to-be-processed holding part, wherein the conductive layer of the processing surface contacted with the processing liquid is used as a second electrode. A contact member that is in electrical contact with a peripheral portion of the processing target; and a sealing member that is provided on the processing target holding portion and seals the peripheral portion of the processing target that is in electrical contact with the processing surface from the processing liquid that contacts the processing surface. The seal member to be processed and the object holding portion holding the object to be processed are retracted from the processing tank and moved to the processing tank while the sealed peripheral edge of the object is kept in a sealed state. A transfer mechanism of the processing body holding unit,
A liquid processing method using a liquid processing apparatus having a cleaning mechanism for cleaning the retracted workpiece holding unit including the processing surface of the workpiece held therein. here,
The processing is performed such that electrical contact is made between the peripheral portion of the object to be processed and the contact member, and a sealed state of the peripheral portion of the object that is electrically contacted is established with the seal member. Holding the object to be processed in the object-to-be-processed holding section; contacting the processing surface of the held object to be processed with the processing liquid stored in the processing bath; and contacting the contact member with the first member. Supplying electricity between the electrodes and processing the processing surface; and the cleaning mechanism by the transfer mechanism while the processing object holding unit holding the processing object after the processing is kept in the sealed state. And a step of cleaning the evacuated workpiece holding section including the processing surface of the workpiece held therein (claim 6).

That is, the sealing state of the peripheral portion of the object to be electrically contacted with the contact member provided on the object holding portion is maintained until the object holding portion is retracted from the processing tank by the transfer mechanism. Is done. After retreating the object-to-be-processed holding part from above the processing tank, it is cleaned including the processing surface of the object to be processed.

Therefore, in the same manner as described above, it is possible to ensure the contact of the electric contact for supplying electricity to the object to be processed for the liquid phase treatment, and to reliably seal this electric contact from the processing liquid. Become.

[0025]

According to a preferred embodiment of the present invention, in the liquid processing apparatus according to the first aspect, the cleaning mechanism further includes a cleaning unit that is provided when the workpiece holding unit does not hold the workpiece. The contact member and the seal member are cleaned (claim 2).

According to this, in the processing tank, contamination when the processing liquid reaches the sealed contact member or the sealing member as mist in the atmosphere can also be removed. Therefore, it is possible to further ensure the contact of the electric contact for supplying electricity to the object to be processed for the liquid phase treatment, and to reliably seal the electric contact from the processing liquid.

As a preferred embodiment, the liquid processing apparatus according to claim 1, further comprising a workpiece transport mechanism for transporting a workpiece to be held by the workpiece holding unit, The body transport mechanism transfers the object to be held to the object holding part when the object holding part is located closer to the cleaning mechanism than the processing tank (Claim 3). ).

According to this, the standby place of the object-to-be-processed holding section can be set to a place different from the atmosphere of the processing liquid mist. Therefore, contamination of the contact member and the seal member provided in the processing object holding portion with the processing liquid can be still reduced. Therefore, it is possible to further ensure the contact of the electric contact for supplying electricity to the object to be processed for the liquid phase treatment, and to reliably seal the electric contact from the processing liquid.

As a preferred embodiment, the liquid processing apparatus according to claim 1, further comprising a workpiece transport mechanism for transporting the cleaned workpiece, wherein the workpiece transport mechanism comprises: Receiving the cleaned object from the object holding portion is performed when the object holding portion is closer to the cleaning mechanism than the processing tank (claim 4).

According to this, the object to be processed can be directly carried out from the object holding mechanism located in the cleaning mechanism after the cleaning, and therefore, the object to be processed can be rationally transferred to the next step. .

As a preferred embodiment, the liquid processing apparatus according to claim 4, further comprising a second cleaning mechanism for etching and cleaning a peripheral portion of the cleaned object to be cleaned, wherein the cleaning mechanism cleans the peripheral portion. The movement of the processed object from the processed object holding unit to the second cleaning mechanism is performed by the processed object transport mechanism, and the second cleaning mechanism includes the second cleaning mechanism and the processing unit. The cleaning mechanism is arranged so as to be located between the tank and the tank (claim 5).

According to this, it is possible to move the object to be processed to the second cleaning mechanism at a place remote from the processing tank, and to perform the above-mentioned "positioning in the cleaning mechanism after cleaning". The object to be processed can be directly carried out of the object to be processed holding mechanism ", and the object to be cleaned can be kept as far away from the processing tank as possible. Therefore, contamination of the object to be processed by the processing liquid mist is reduced, and the load of cleaning by the second cleaning mechanism can be reduced.

According to a preferred embodiment of the present invention, in the liquid processing method according to claim 6, the object to be processed is held before the object to be processed is held in the object holding portion or the cleaning mechanism is retracted to the cleaning mechanism. After cleaning the processing object holding part,
The method further includes a step of cleaning the contact member and the seal member by the cleaning mechanism.
According to this, the operation and effect are exhibited in the same manner as described in claim 2.

As a preferred embodiment, in the liquid processing method according to claim 6, the step of holding the object to be processed in the object holding portion includes the step of: This is performed when the washing mechanism is located closer to the washing mechanism than the tank (claim 8). According to this, the operation and effect are exhibited in the same manner as described in the third aspect.

As a preferred embodiment, in the liquid processing method according to claim 6, when the object-to-be-processed holding part is located closer to the cleaning mechanism than the processing tank, the cleaned object-to-be-processed. Is further received by the processing object transport mechanism from the processing object holding unit (claim 9). According to this, the operation and effect are exhibited in the same manner as described in the fourth aspect.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front sectional view schematically showing the vicinity of a processing tank of a liquid processing apparatus according to an embodiment of the present invention. FIG. 1 exemplifies, as a liquid processing apparatus, a plating apparatus which forms wiring and vias between wirings on a surface of a semiconductor wafer as an object to be processed by plating. It shows a plating section. As shown in FIG. 1, the plating section 10 is entirely covered with a housing 12 having a closed structure. This housing 12
Is made of a plating liquid resistant material such as a synthetic resin.

The inside of the housing 12 has a structure divided into two stages, upper and lower, that is, a first processing unit located at a lower stage and a second processing unit located at an upper stage. The first processing section and the second processing section are separated by a separator 23 having a built-in exhaust port 22. At the center of the separator 23, the wafer 21 held by the wafer holding
A through hole is provided so as to be able to move back and forth between the processing unit and the second processing unit.

Further, the housing 12, which is located slightly above the boundary between the first processing section and the second processing section and reaches a guide rail 15, which will be described later, has a wafer holding section 17 together with its driving section 14 in the plating processing section 10. There is provided a gate valve 18 for moving or retreating from the plating processing section 10. When the gate valve 18 is closed, the inside of the plating unit 10 becomes a space separated from the space outside the plating unit 10, so that the diffusion of dirt from the plating unit 10 into the outside space is prevented.

A plating solution tank 24 as a processing tank is provided inside the first processing section. This plating solution tank 24
Is provided with an outer tank 25 arranged concentrically on the outside thereof. When the plating solution tank 24 is filled with the plating solution,
The plating solution tank 2 is arranged such that the surface to be plated of the wafer 21 at a plating position (IV) described later is lower than the plating solution level.
4 is fixed.

The plating solution tank 24 is formed in a substantially cylindrical shape with a bottom, and the opening surface of the plating solution tank 24 is maintained substantially horizontal. The plating bath 2 is provided inside the plating bath 24.
An ejection pipe 29 for ejecting the plating solution from the bottom surface side of the plating solution 4 toward the upper surface protrudes from substantially the center of the bottom surface of the plating solution tank 24 to almost the middle in the depth direction of the plating solution tank 24. Around the ejection pipe 29, an approximately disk-shaped anode electrode 27 as a first electrode is disposed concentrically with the plating solution tank 24. The anode electrode 27 is placed in a plating solution containing, for example, copper sulfate. To keep the copper ion concentration in the plating solution constant.

A lead wire is extended from the anode electrode 27 to an external power supply (not shown) outside the outer tank 25. When the power supply is turned on, an electric field is generated between the anode electrode 27 and the wafer 21. Is formed.

Between the outer periphery of the end of the jet pipe 29 and the plating solution tank 24, the diaphragm 2 for dividing the plating solution tank 24 into upper and lower parts.
6 is provided above the anode electrode 27 and the diaphragm 2
The plating solution as the first processing solution is supplied from the ejection pipe 29 to the upper side of the plating solution tank 24 partitioned in 6 (hereinafter referred to as “upper side of the plating solution tank”), and the plating solution partitioned by the diaphragm 26. A plating solution as a second processing solution is supplied to the lower side of the tank 24 (hereinafter, referred to as “the lower side of the plating solution tank”) from a circulation pipe 28 described later. Also,
The diaphragm 26 transmits ions, but the anode electrode 27
Are dissolved so as to prevent impurities such as oxygen and hydrogen generated during the plating process from passing through the surface to be plated of the wafer 21 such as oxygen and hydrogen.

Circulation pipes 28 and 30 are provided at positions eccentric from the center of the bottom surface of the plating solution tank 24, and a pump (not shown) is provided between the circulation pipes 28 and 30. By operating this pump, the plating solution is circulated below the plating solution tank 24.

The outer tank 25 is formed in a substantially cylindrical shape with a bottom similarly to the plating solution tank 24, and the opening surface of the outer tank 25 is maintained substantially horizontal. The bottom of the outer tank 25 has two outlets.
The outlet 32 is connected to a pipe 32. A pump 31 is provided between the pipe 32 and the ejection pipe 29. A tank (not shown) containing a plating solution is connected to the pipe 32 via a pump and a valve, and the pump is operated to open the valve so that the plating solution in the tank is removed from the plating solution tank 24. Can be supplied.

On the other hand, inside the second processing unit, the wafer 2
Wafer holding unit 17 as an object holding unit for holding the wafer 1
Is disposed right above the center of the plating solution tank 24. Further, the wafer holding unit 17 is capable of rotating the wafer 21 together with the wafer holding unit 17 in a substantially horizontal plane, and is suspended from a driving unit 14 that moves the wafer holding unit 17 up and down.

The driving section 14 is covered with a cover made of a plating liquid resistant material such as a synthetic resin, and prevents the mist from evaporating and scattering the plating liquid from entering the driving section 14. Preventing. The drive section 14 is disposed on a guide rail (corresponding to a transfer mechanism of a workpiece holding section) 15 which is disposed substantially horizontally and extends outside the plating section 10 so as to be movable leftward in the drawing. As a result, the driving unit 14 and the wafer holding unit 17
Together with the wafer 21 held in the plating section 10, and can be retreated from the plating section 10.

The vertical movement of the wafer holding unit 17 by the drive unit 14 is, specifically, a process in which the wafer 21 placed on the wafer holding unit 17 is moved from the initial position (I) to the spin position for performing spin drying described later. The process is performed so as to move up and down between a dry position (II) and a plating position (III) for forming a plating layer on a surface to be plated of the wafer 21. The initial position (I) is above the plating solution level when the plating solution is filled in the plating solution tank 24, and the spin dry position (II) and the plating position (III) are below the plating solution level. It is in.

The wafer holding portion 17 is formed in a substantially cylindrical shape, and can hold one wafer 21 substantially horizontally inside the wafer holding portion 17. A substantially circular opening is formed in the bottom surface of the wafer holding unit 17, and a plating layer can be formed on the surface of the wafer 21 held inside the wafer holding unit 17, which is to be plated as a second electrode. I can do it.

The wafer 21 held by the wafer holder 17
A thin film of copper, a so-called seed layer, is previously formed on another surface of the wafer 21 by another apparatus, and a voltage applied to a cathode contact member described later is also applied to the surface of the wafer 21 to be plated. ing.

Further, the wafer holding section 17 is provided with a wafer pressing mechanism 19 and a contact / seal presser 20. The back surface of the wafer 21 placed on the wafer holding unit 17 is pressed by the wafer pressing mechanism 19 to ensure electrical contact between the wafer 21 and the contacts.
The wafer pressing mechanism 19 is disposed so as to be able to uniformly press the wafer 21 toward the outer periphery in the circumferential direction, and moves up and down independently of the wafer holding unit 17.

The contact / seal press 20 presses and fixes a cathode contact member and a seal member, which will be described later, to the wafer holding section 17. The contact / seal retainer 20 is disposed so as to coincide with the circumferential direction of the wafer holding unit 17.

Next, the structure of a cleaning unit (corresponding to a cleaning mechanism) in the plating apparatus of this embodiment is shown in FIG.
This will be described with reference to FIG. FIG. 1 is a front sectional view schematically showing a cleaning unit in the plating apparatus according to this embodiment, and the same reference numerals are given to the components already described.

As shown in FIG. 2, the cleaning section 40 is entirely covered with a housing 33 having a closed structure. On the side wall of the housing 33, a gate valve for moving the wafer holding unit 17 together with the driving unit 14 into or out of the cleaning unit 40, corresponding to the height up to the guide rail 15. 34 are provided. When the gate valve 34 is closed, the inside of the cleaning unit 40 becomes a space separated from the space outside the cleaning unit 40, so that contamination from the outside space can be prevented. In addition, it is possible to prevent the jetted cleaning liquid and the jet gas for removing the cleaning liquid from the object to be cleaned from being diffused to the outside when cleaning.

Although not shown in the figure, in addition to the gate valve 35, a gate valve is provided in the housing 33 on the wall surface parallel to the plane of the drawing for carrying the wafer 21 into and out of the wafer holding portion 17.

The guide rail 15 is extended outside the cleaning section 40, that is, integrally formed with the guide rail 15 shown in FIG. 1, and provided between the cleaning section 40 and the plating section 10. , The driving unit 14, the wafer holding unit 17, and the wafer 21 held by the wafer holding unit 17 can move at the same time.

The drive section 14 also raises and lowers the wafer holding section 17 in the cleaning section 40. Specifically, loading / unloading for loading / unloading the wafer 21 into / from the wafer holding unit 17 is performed.
It is moved up and down between the carry-out position (I) and the cleaning position (III) for cleaning the surface to be plated of the wafer 21 and the wafer holding portion 17. In addition, when performing cleaning and drying, the wafer holding unit 17 can be rotated in the horizontal direction.

The loading / unloading position (I) is set at the plating section 1
The cleaning position (III) is almost the same height as the initial position (I) at 0 and the plating position (III) in the plating unit 10. With such a height setting, the wafer holding unit 17 can be
At 0, the state of being lowered for the plating process is reproduced in the cleaning unit 40, so that not only the wafer holding unit 17 but also the drive shaft from the driving unit 17 of the wafer holding unit 17 can be cleaned.

A large number of cleaning liquid ejection / gas ejection nozzles 35 are provided on the inner wall surface of the housing 33 so that the wafer holding unit 17 and the drive unit 14 are ejected. Also,
A cleaning liquid jet / gas jet nozzle 36 is disposed on the bottom surface of the housing 33 so that the cleaning liquid and gas are jetted efficiently onto the surface of the wafer 21 mainly held by the wafer holding unit 17.

As the cleaning liquid, for example, pure water can be used, and as the drying gas, for example, an inert gas such as nitrogen gas can be used.

At the substantially bottom center of the housing 33, a discharge pipe 37 for collecting the cleaning liquid and discharging the jetted gas is provided.
Is provided.

Next, details of the mounting state of the wafer 21 on the wafer holder 17 in this embodiment will be described with reference to FIG. FIG. 3 is a schematic front sectional view for explaining a state where the wafer 21 is placed on the wafer holding unit 17. The same reference numerals are given to the components already described in FIG.

As shown in FIG. 3, the wafer holding unit 17
A cathode contact member 42 for applying a voltage to the plating surface of the wafer 21 is disposed inside the side member 17a and the bottom member 17b. The cathode contact member 42 is formed of a conductive material, and includes a portion formed in a ring shape in the circumferential direction of the wafer holding portion 17 and a contact portion protruding from this portion. I have.

The contact portion has at least one ring-shaped portion.
More than one part is formed integrally. Further, it is preferable that the number of contact portions in all the circumferential directions of the wafer is 6 to 180. The reason for this is that, for example, a wafer 2 having a diameter of 30 cm
This is because if the number exceeds 1, even if the number exceeds 180, deficiencies in processing are likely to occur in production, and if the number is less than the above range, the plating current distribution on the surface to be plated of the wafer 21 becomes difficult to be uniform.

A lead wire is connected to the cathode contact member 42 so that a voltage can be applied from an external power supply (not shown) via the lead wire.

The contact portion of the wafer 21 with the contact member 42 is sealed by the seal member 41 to prevent the plating solution from entering. The seal member 41 is used for the wafer holder 1.
7 are arranged in a ring shape in the circumferential direction, and project in a ring shape in a direction facing the wafer 21. The sealing member 41 is made of, for example, rubber having elasticity, and
The back surface of the wafer 21 is elastically deformed by being pressed downward by the wafer pressing mechanism 19 to ensure the sealing property between the wafer 21 and the surface to be plated.

According to the plating apparatus as described above, the contact member 42 provided on the wafer holder 17 is provided.
The sealing state of the peripheral portion of the wafer 21 that makes electrical contact with
The wafer holding unit 17 is moved from the plating solution tank 24 to the guide rail 1.
Even if it moves to the washing | cleaning part 40 by 5, it is maintained as it is.
Then, after retreating from the plating solution tank 24 of the wafer holding unit 17 to the cleaning unit 40, this is cleaned including the surface to be plated of the wafer 21.

Therefore, the plating surface of the wafer 21 and the wafer holding portion 17 can be sufficiently cleaned by the cleaning portion 40 different from the plating solution tank 24 without paying attention to the mixing of the cleaning solution into the plating solution. In addition, this cleaning unit 40
Is a space which is installed in a place different from the plating solution tank 24 and in which the plating solution mist does not exist in the cleaning atmosphere. Therefore, the cleaning effect of removing the plating solution component on the surface to be plated and the wafer holding portion 17 is sufficiently exhibited.

Thus, contamination of the contact member 42 and the seal member 41 provided on the wafer holding part 17 is greatly reduced even when the sealing state is released. Therefore, it is possible to ensure the contact of the electric contact for supplying electricity to the wafer 21 for the liquid phase processing, and to reliably seal this electric contact from the plating solution.

In the plating apparatus configured as described above, the wafer 2 to be held by the wafer
The transfer of 1 can be performed in the cleaning unit 40. That is, when the wafer holding unit 21 is on standby to receive the wafer 21, the wafer holding unit 17 can be placed in an atmosphere in which the plating solution mist does not exist.

Therefore, contamination of the contact member 42 and the seal member 41 provided on the wafer holding portion 17 by the plating solution can be further reduced. Therefore,
Further, it is possible to ensure the contact of the electric contact for supplying electricity to the wafer 21 for the liquid phase processing, and to reliably seal the electric contact from the plating solution.

In this plating apparatus, the cleaning unit 4
The cleaning by 0 may be further performed on the contact member 42 and the seal member 41 by the cleaning liquid ejection / gas ejection nozzle 36 when the wafer holding unit 17 is not holding the wafer 21.

According to this, for example, the plating section 10
In the above, the contamination when the plating solution reaches the sealed contact member 42 or the sealing member 41 as an mist in the atmosphere can be washed and removed. Therefore, it is possible to further ensure the contact of the electric contact for supplying electricity to the wafer 21 for the liquid phase processing, and to reliably seal the electric contact from the plating solution.

Next, the operation of the plating apparatus according to the embodiment of the present invention having the above configuration will be described with reference to FIG. FIG. 4 is a flowchart showing an operation flow of the plating apparatus according to the embodiment of the present invention.

First, the gate valve provided on the side wall of the cleaning unit 40 is opened, and the arm carrying the unprocessed wafer (corresponding to the workpiece transfer mechanism) is extended to move the wafer into / from the loading / unloading position. The wafer is placed on the wafer holding unit 17 waiting at I). Here, in detail, the wafer holding unit 17
As shown in (1), the wafer 21 is received so as to be placed on the contact point of the contact member 42 (step 81).

After the wafer 21 is placed on the contact member 42, the arm retracts to close the gate valve, and the wafer pressing mechanism 19 provided in the wafer holder 17
Presses the back surface of the wafer 21 (step 82).
Due to this pressing, the protrusion of the seal member 41 is surely elastically deformed to generate a compressive stress and repel the contacting wafer 21, so that the plating solution can be prevented from entering the inside of the wafer holding portion 17. That is, thereby, the contact between the wafer 21 and the contact member 42 and the sealing state thereof are established.

Next, the gate valve 34 is opened, and the wafer holding unit 1 holding the wafer 21 is guided by the guide rail 15.
7 and the drive unit 14 move toward the plating unit 10 (step 83). At this time, in the plating unit 10, the gate valve 18 is opened, and the moving wafer holding unit 17 holding the wafer 21 and the driving unit 14 are received, and are positioned immediately above the plating solution tank 24. At this time, the wafer holding unit 17 is at the initial position (I). The plating solution tank 24 of the plating section 10 is filled with a plating solution.

Thereafter, the gate valve 18 is closed, and while the wafer 21 is maintained in the above-mentioned sealed state, the wafer holding unit 17 is lowered by the driving of the driving unit 14 to position the wafer 21 at the plating position (III). Thereafter, a voltage is applied between the anode electrode 27 and the cathode contact member 42, and the plating surface of the wafer 21 is plated with, for example, copper (Step 84). During the plating process, the wafer holding unit 17 is rotated by the drive unit 14 to improve the processing non-uniformity of the wafer 21 caused by the plating solution flow.

After a plating layer having a sufficient thickness is formed on the surface to be plated of the wafer 21, the application of the voltage is stopped. And
A predetermined amount of the plating solution is returned to a tank (not shown), and the level of the plating solution in the plating solution tank 24 is lowered. After the level of the plating solution is lowered, the wafer holding unit 17 is raised by the drive of the driving unit 14 to position the wafer 21 at the spin dry position (II).

In this state, the wafer holding unit 17 is
Then, the substrate is rotated in a substantially horizontal plane and spin-dried to remove excess plating solution adhering to the plating surface of the wafer 21 (step 85).

After spin-drying is sufficiently performed, the wafer holding unit 17 is raised by the driving of the driving unit 14 to position the wafer 21 at the initial position (I) (step 86). Then, the gate valve 18 is opened, and the wafer holding unit 17 holding the plated wafer 21 and the driving unit 14 are moved from the plating bath 24 along the guide rail 15 to the cleaning unit 40.
Retreat in the direction (step 87). At this time, the cleaning unit 4
At 0, the gate valve 34 opens to receive the wafer holding unit 17 holding the plated wafer 21 and the driving unit 14. When received, the wafer holding unit 17 is at the carry-in / out position (I) in the cleaning unit 40, and the sealed state of the contact member 42 is maintained.

Next, the gate valve 34 is closed, and the wafer holding unit 17 is lowered in the cleaning unit 40 to the cleaning position (II).
I) (step 88). Then, the cleaning liquid is jetted from the cleaning liquid jet / gas jet nozzles 35 and 36 to sufficiently wash the surface to be plated of the wafer 21, the wafer holding unit 17, and the driving unit 14 (Step 89). At this time, the effect of cleaning the surface to be plated of the wafer 21 can be improved by rotating the wafer holding unit 17.

After the cleaning is completed, a gas for drying is discharged from the cleaning liquid jetting / gas jetting nozzles 35 and 36 to sufficiently dry the surface to be plated of the wafer 21, the wafer holding unit 17, and the driving unit 14. (Step 90). At this time,
Spin drying by rotating the wafer holding unit 17 may be used together.

When the drying is completed, the driving unit 14 moves the wafer holding unit 17 to the loading / unloading position (I). In this state, a gate valve provided on the side wall of the cleaning unit 40 is opened, and the arm 21 (corresponding to a workpiece transfer mechanism) extending the plated wafer 21 through the gate valve.
(Step 91). Therefore, at this point, the state of sealing to the wafer 21 is released. Therefore, the contamination of the contact member 42 and the seal member 41 provided on the wafer holding unit 17 is greatly reduced by opening the sealed state after the sufficient cleaning. Therefore, it is possible to ensure the contact of the electric contact for supplying electricity to the wafer 21 for the liquid phase processing, and to reliably seal this electric contact from the plating solution.

In FIG. 4, steps 92 to 95 are optional steps. That is, as described above, when the wafer holding unit 17 does not hold the wafer 21, the cleaning member jetting / gas jetting nozzle 36 further cleans the contact member 42 and the seal member 41.

According to this, for example, the plating solution processing unit 1
At 0, contamination when the plating solution reaches the sealed contact member 42 or the sealing member 41 as mist in the atmosphere can also be washed and removed.

The operation will be described. First, after the wafer 21 is unloaded from the wafer holding section 17, the wafer holding section 17
Is the cleaning position (II)
It falls to I) (step 92). Then, the cleaning liquid is ejected from the cleaning liquid ejection / gas ejection nozzle 36 to wash the contact member 42 and the seal member 41 (step 9).
3). At this time, the wafer holding unit 17 can be rotated by the driving unit 14 to improve the cleaning effect.

When cleaning is sufficient, a gas for drying is blown out from the cleaning liquid blowout / gas blowout nozzle 36 to sufficiently dry the contact member 42 and the seal member 41 provided on the wafer holder 17 (step 94). . At this time,
Spin drying by rotating the wafer holding unit 17 may be used together.

When the drying is completed, the wafer holding unit 17 is raised by the driving unit 14 and is positioned at the loading / unloading position (I). As a result, the next unprocessed wafer can be received.

Note that steps 92 to 95
May be performed every time a plurality of wafers are processed, instead of every time. This is because the contamination of the contact member 42 and the seal member 41 located inside the wafer holding unit 17 by the plating solution mist is smaller than the plating surface of the wafer 21, the wafer holding unit 17, and the driving unit 14. Because it can be done.

Next, an embodiment of an apparatus in which a second cleaning unit as a second cleaning mechanism is added to the plating apparatus as described above and these processings are systematized will be described with reference to FIG.
This will be described with reference to FIG.

FIG. 9 is a schematic plan view of an embodiment in which a plating apparatus as a liquid processing apparatus according to the present invention is systemized. The plating processing is performed on a semiconductor wafer (object to be processed), and the semiconductor wafer is cleaned. And a system for etching and cleaning (bevel etching) the peripheral portion of the wafer.
The components already described are given the same numbers.

The bevel etching is a seeding layer (seed layer) on a wafer formed in advance for plating.
In this step, the wafer peripheral portion is removed after plating. As described above, in the plating process, electrical contact with the contact member is required at the periphery of the wafer, and the vicinity of the contact member is sealed from the plating solution.
Therefore, no plating is formed at the peripheral portion of the wafer.
Such a conductive layer on which plating is not superimposed is easily peeled off by contact with a transfer mechanism during the transfer of the wafer after plating, and contaminates the apparatus. In order to prevent such contamination, etching is performed after plating is formed.

In the ordinary bevel etching step,
At the same time, there is a case in which the contamination of the back surface of the wafer by the plating solution is cleaned. The plating process is a process in an atmosphere in which a mist of the plating solution is present, and contamination of the plating solution on the back surface of the wafer may occur.

To explain the structure, as shown in the figure, the system comprises a carrier station 52 for transferring a wafer 56 in and out, and a process station 53 for actually processing the wafer 56.

The carrier station 52 has a wafer 56
And a sub-arm 57 for accessing the carrier cassette 55 mounted on the mounting table 54 to take out the wafer 56 stored therein and to store the processed wafer 56. It is configured.

In the carrier cassette 55, a plurality of wafers 56, for example, 25 wafers are housed in a vertical direction while being kept horizontally at equal intervals. Mounting table 54
On the upper side, for example, four carrier cassettes 55 are arranged vertically in the figure.

The sub-arm 57 has a structure capable of moving on a rail arranged in the vertical direction in the figure, ascending and descending in a vertical direction, that is, a direction perpendicular to the plane of the paper in the figure, and rotatable in a horizontal plane. An unprocessed wafer 56 is taken out of the carrier cassette 55 by accessing a carrier cassette 55 placed on the carrier 54, and a processed wafer 56 is stored in the carrier cassette 55.

The sub arm 57 is connected to the relay stand 64
The wafer 56 before and after processing is also transferred to and from a process station 53 to be described later.

The process station 53 has a rectangular parallelepiped or cubic appearance, and its entire periphery is covered with a housing 58 made of a corrosion-resistant material, for example, a resin or a metal plate whose surface is coated with a resin. .

A processing space is formed in the housing 58, and a bottom plate 59 is attached to the bottom of the processing space.

In the processing space, a plurality of processing devices, such as plating units 10a and 10b, cleaning units 40a and 40b, and second cleaning units 50a and 50b, for example, sandwich a main arm 65 described below in the processing space. Are arranged as follows. In addition, these processing apparatuses 10a, 10b, 40
In addition to a, 40b, 50a, and 50b, another processing device (for example, an annealing device that anneals the formed plating layer) is provided vertically above (ie, in a two-stage configuration). Can also. Further, the main arm 65 corresponds to an object transfer mechanism.

The plating sections 10a and 10b in the processing space
Has the same configuration as the plating section shown in FIG. 1, and the cleaning sections 40a and 40b have the same configuration as the cleaning section shown in FIG. Plating unit 10
a and the cleaning unit 40a are connected by the guide rail 15 as described above, and the same applies to the relationship between the plating unit 10b and the cleaning unit 40b.

At the approximate center of the bottom plate 59, a main arm 65 for transferring a wafer is provided. The main arm 65 is vertically movable and rotatable in a horizontal plane. The main arm 65 further includes a wafer holding member that expands and contracts substantially in a horizontal plane. The installed processing device 40
The wafers before and after the processing can be taken in and out of a, 40b, 50a, and 50b. Note that the wafers before and after the processing can be loaded or unloaded to and from the carrier station 52 via the relay table 64.

Incidentally, when the processing apparatus has a two-stage configuration, the main arm 65 can move vertically and enter and exit the upper processing apparatus. Transporting wafers to other processing equipment,
Conversely, a wafer can be carried from an upper processing apparatus to a lower processing apparatus.

Further, as a function of the main arm 65, the above-mentioned wafer holding member can hold the wafer by, for example, vacuum suction, and can rotate the vacuum-sucked wafer in a horizontal plane.

The main arm 65 has a function of turning the held wafer upside down, and has a structure which can turn the wafer upside down while transferring the wafer from one processing apparatus to another processing apparatus. . Note that the wafer reversing function is not an essential function of the main arm 65.

The procedure for processing a wafer as a system including the plating units 10a and 10b, the cleaning units 40a and 40b, and the second cleaning units 50a and 50b is as follows. It is conveyed to a space, and is carried into either the cleaning unit 40a or the cleaning unit 40b. In the cleaning units 40a and 40b, a series of operations are performed as described with reference to FIG.
a and 10b.

When this process is completed, the cleaning units 40a, 40a
The main arm 65 receives the wafer from 0b, moves and carries the wafer into the second cleaning unit 50a or 50b, and performs bell etching on the wafer. When the bevel etching in the second cleaning unit 50a or 50b is completed, the processed wafer is returned to the carrier station 52 side by the main arm 65 via the relay table 64.

Continuing the description of the structure, an opening is provided in a housing 58a disposed at a position facing the carrier station 52 in the housing 58 of the process station 53. The opening corresponds to the relay table 64 and is used when an unprocessed wafer taken out by the sub arm 57 from the carrier cassette 55 is carried into the process station 53. At the time of loading, the opening is opened, and the sub-arm 57 holding the unprocessed wafer extends the wafer holding member into the processing space to access it, and places the wafer on the relay table 54. The main arm 6
5 accesses and holds the wafer placed on the relay stand 64 and carries it into a processing unit such as a plating unit.

The opening of the housing 58a is
It can also be provided at a position directly corresponding to the cleaning units 50a and 50b. By doing so, the wafer subjected to these processes can be taken out to the carrier station 52 side without passing through the main arm 65.

FIG. 6 is a front view of the system shown in FIG. In FIG. 6, the elements already described are given the same reference numerals, and reference numeral 70 is a top plate of the process station 53.

In the systemized apparatus as shown in FIGS. 5 and 6, the loading / unloading of the wafer by the main arm 65 is not performed directly to the plating units 10a and 10b, and the cleaning units 40a and 40b are not used. And the second cleaning unit 50
Since a and 50b are adjacent to each other, the transfer of the wafer between the apparatuses can be performed rationally in the shortest time.

Further, the wafer is held by the wafer holding unit via the cleaning units 40a and 40b, and then the plating processing unit 10
a, 10b, where the cleaning units 40a, 40b
Therefore, the chance that the back surface of the wafer is exposed to the atmosphere in which the mist of the plating solution is present becomes very small. Therefore, there is almost no contamination of the back surface of the wafer by the plating solution, and therefore, there is an effect that the burden of cleaning the back surface of the wafer in the bevel etching step can be reduced.

[0115]

As described in detail above, according to the present invention,
The sealing state of the peripheral portion of the object to be processed, which is in electrical contact with the contact member provided on the object holding portion, is maintained even if the object holding portion is retracted from the processing tank by the transfer mechanism. Therefore, it is possible to sufficiently clean the processing surface and the object-to-be-processed holding part by a cleaning mechanism different from the processing tank without paying attention to the mixing of the cleaning liquid into the processing liquid. Can be installed in another place, so that it is easy to set the cleaning atmosphere to a space where the processing liquid mist does not exist. Therefore, the cleaning effect of removing the plating solution component on the processing surface and the processing object holding portion is sufficiently exhibited, and even when the sealing state is opened, the contact member and the sealing member provided on the processing object holding portion are greatly contaminated. It is reduced. Therefore, it is possible to ensure the contact of the electric contact for supplying electricity to the object to be processed for the liquid phase treatment, and to reliably seal the electric contact from the processing liquid.

[Brief description of the drawings]

FIG. 1 is a front sectional view schematically showing the vicinity of a processing tank of a liquid processing apparatus according to an embodiment of the present invention.

FIG. 2 is a front sectional view schematically showing a cleaning unit in the plating apparatus of the embodiment shown in FIG. 1;

FIG. 3 is a schematic front sectional view for explaining a mounting state of a wafer 21 on a wafer holding unit 17 in FIGS. 1 and 2;

FIG. 4 is a flowchart showing an operation flow of the plating apparatus according to the embodiment of the present invention shown in FIGS. 1, 2 and 3;

FIG. 5 is a schematic plan view of an embodiment in which a plating apparatus as a liquid processing apparatus according to the present invention is systematized.

FIG. 6 is a view showing the system shown in FIG. 5 as a front view.

[Explanation of symbols]

10, 10a, 10b: Plating section 12: Housing 14, Drive section 15: Guide rail 17: Wafer holding section 17a: Side member 17b: Bottom member 18: Gate valve 19: Wafer pressing mechanism 19 20: Contact / seal press 21 ... wafer 22 ... exhaust port 23
... Separator 24 ... Plating solution tank 25 ... Outer tank 27 ...
Anode electrode 28, 30: Circulation pipe 29: Spout pipe
31 ... Pump 32 ... Piping 33 ... Housing 34 ...
Gate valves 35, 36: Cleaning liquid ejection / gas ejection nozzle 37: Discharge pipes 40, 40a, 40b: Cleaning section 5
0a, 50b: second cleaning section 52: carrier station 53: process station 54: mounting table 55
... Carrier cassette 56 ... Wafer 57 ... Sub arm 58 ... Housing 58a ... Housing 59 ... Bottom plate 64 ... Intermediate stand 65 ... Main arm 70 ... Top plate

Claims (9)

[Claims] 1. A processing tank having a first electrode capable of storing a processing liquid and being immersed in the stored processing liquid, and holding a processing target and contacting a processing surface with the processing liquid. An object-to-be-processed holding part to be processed, and an electric conductive layer provided on the object-to-be-processed holding part and electrically connected to a peripheral portion of the object to be processed so that a conductive layer of the processing surface brought into contact with the processing liquid is used as a second electrode. A contact member that is in contact with; a seal member that is provided on the processing object holding unit and seals a peripheral edge of the processing object that is in electrical contact with the processing liquid that contacts the processing surface; The object-to-be-processed holding portion holding the object to be processed, while the sealed peripheral portion of the object to be processed is kept in a sealed state,
A transfer mechanism of an object-to-be-processed holding unit that retreats from the processing tank and moves to the processing tank; and cleans the retracted object-to-be-processed holding unit including the processing surface of the object to be processed held therein. And a cleaning mechanism. 2. The cleaning mechanism according to claim 1, wherein the cleaning mechanism further cleans the contact member and the seal member when the processing object holding unit does not hold the processing object. Liquid treatment equipment. 3. The apparatus according to claim 1, further comprising a processing object transport mechanism configured to transport the processing object to be held by the processing object holding unit, wherein the processing object transport mechanism performs the processing of the processing object to be held. 2. The liquid processing apparatus according to claim 1, wherein the delivery to the body holding unit is performed when the processing object holding unit is located closer to the cleaning mechanism than the processing tank. 3. 4. The apparatus according to claim 1, further comprising: an object transfer mechanism configured to transfer the cleaned object to be processed.
2. The apparatus according to claim 1, wherein receiving the cleaned object from the object holding part is performed when the object holding part is located closer to the cleaning mechanism than the processing tank. Liquid processing equipment. 5. A cleaning apparatus according to claim 1, further comprising a second cleaning mechanism for etching and cleaning a peripheral portion of said cleaned object, wherein said second cleaning mechanism cleans said peripheral part from said workpiece holding part by said cleaning mechanism. The movement to the cleaning mechanism 2 is performed by the object transfer mechanism, and the second cleaning mechanism is arranged such that the cleaning mechanism is located between the second cleaning mechanism and the processing tank. The liquid processing apparatus according to claim 4, wherein: 6. A processing tank having a first electrode capable of storing a processing liquid and being immersed in the stored processing liquid, and holding a processing target and contacting a processing surface with the processing liquid. An object-holding portion to be processed, and an electrical connection provided on the object-holding portion and electrically connected to a peripheral portion of the object to be processed so that a conductive layer on the processing surface brought into contact with the processing liquid is used as a second electrode. A contact member that contacts, a seal member that is provided in the processing object holding unit, and seals a peripheral portion of the processing object that is in electrical contact with the processing liquid that contacts the processing surface; and the processing object. The transfer mechanism of the processing object holding unit that retracts from the processing tank and moves the processing object to the processing tank, while the processing target holding unit holding the object, while keeping the sealed processing target peripheral edge in a sealed state, The evacuated workpiece holder is held there. A liquid processing method using a liquid processing apparatus having a cleaning mechanism for cleaning the processing object including the processing surface of the processing object, wherein an electrical contact is made between the peripheral portion of the processing object to be processed and the contact member. Holding the object to be processed in the object holding portion so that the sealing member establishes a sealing state of the peripheral portion of the object to be electrically contacted with the sealing member; and Contacting the treatment surface of the object to be treated with the treatment liquid contained in the treatment tank, and supplying electricity between the contact member and the first electrode to treat the treatment surface. Retreating the workpiece holding unit holding the workpiece after the processing to the cleaning mechanism by the transfer mechanism in the sealed state; and storing the retracted workpiece holding unit therein. The processed object held Washing the body including the treated surface of the body. 7. The contact member and the seal member before the object to be processed is held in the object holding portion or after the object holding portion retracted to the cleaning mechanism is washed. 7. The liquid processing method according to claim 6, further comprising the step of: 8. The step of holding the object to be processed in the object holding part is performed when the object holding part is located closer to the cleaning mechanism than the processing tank. The liquid processing method according to claim 6, wherein 9. A step in which the object transport mechanism receives the cleaned object from the object holder when the object holder is located closer to the cleaning mechanism than the processing tank. 7. The liquid processing method according to claim 6, further comprising: