JP2003201600A - Plating apparatus, and semiconductor device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plating apparatus capable of reducing the treating and manufacturing loads and performing the plating of high quality, and to provide a semiconductor device manufacturing method. <P>SOLUTION: The plating apparatus comprises an electrolyte basin filled with electrolyte in which a conductive layer formed on a treatment surface is brought into contact with a first electrolyte to perform the plating on the conductive layer, an electrolyte tank to store the first electrolyte fed to the electrolyte basin and the first electrolyte discharged from the electrolyte basin, and a first electrolyte circulating passage to feed the first electrolyte from the electrolyte tank to the electrolyte basin and discharge the first electrolyte to the electrolyte tank from the electrolyte basin, and a deaeration mechanism to deaerate gas bubbles in the electrolyte is provided on an electrolyte feed passage of the first electrolyte circulation passage. Small bubbles in the electrolyte are removed, and no small bubbles are adhered to the surface of a work even when the feed of the electrolyte to the electrolyte basin is reduced. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating apparatus for plating an object to be processed and a method for manufacturing a semiconductor device including a step of plating the object to be processed, and particularly to a high processing cost and a low manufacturing load. The present invention relates to a plating processing apparatus suitable for forming a high quality plating, and a method for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In recent years, a plating process in a semiconductor manufacturing process or a liquid crystal device manufacturing process is more frequently replaced with a reaction process in a vapor phase state due to miniaturization of processing required for manufacturing a semiconductor device or a liquid crystal device. Are being used for.

In such a plating process, it is an important issue to control the quality of the semiconductor or the like to be manufactured, to ensure the film quality and thickness uniformity of the plating on the surface of the object to be processed.

Here, as an example, the process of plating the surface of the wafer to be processed with copper will be described.

When copper is plated on the surface of a wafer to be processed, a conductive seeding layer which becomes a cathode for electroplating and serves as a seed for plating is formed on the surface in advance.

The wafer to be processed on which the seeding layer is formed is immersed in a plating solution tank filled with a plating solution based on copper sulfate, for example, and an electric conductor is brought into contact with the seeding layer from the outer periphery of the wafer for electrolytic plating. Is supplied with electricity. In the plating solution tank, a copper anode electrode containing, for example, phosphorus is provided in contact with the plating solution.

A flow of the plating solution is created toward the surface of the wafer to be processed which is immersed in the plating solution tank so that the plating solution is kept uniform in the tank and the plating solution containing a fresh additive is always supplied. . Therefore, a jetting pipe for the plating liquid is provided in a portion of the plating liquid tank facing the surface of the wafer to be processed, and a pump for jetting the plating liquid is arranged on the extension of the root of the jetting pipe.

Further, in response to an increase in the plating solution in the plating solution tank due to the ejection of the plating solution, the plating solution overflowing from the plating solution tank is recovered and circulated so as to eject the plating solution again from the ejection pipe. A plating solution circulation system is formed.

A plating solution tank for managing and storing a plating solution containing an additive is provided in the middle of the plating solution circulation system, and a pipe for supplying the plating solution is provided between the plating solution tank and the plating solution tank. And piping for discharging is provided.

Using these structures, the plating layer was initially supplied with electricity while maintaining the uniformity of the plating solution in the bath and constantly supplying the plating solution containing a fresh additive, while supplying electricity between the cathode and the anode. Copper is reduced and deposited on the cathode, and copper is formed as plating on the seeding layer.

[0011]

By the way, the flow of the plating solution for maintaining the uniformity of the plating solution in the plating solution tank and constantly supplying the plating solution containing a fresh additive should achieve its purpose. The flow velocity is set high enough to allow the flow rate, that is, the flow rate is set large. For this reason, generally, the pump for ejecting the plating solution becomes large in size, the plating solution circulation system becomes large, and the burden for the plating process and the device manufacturing burden are large.

On the other hand, improvements have been attempted with regard to the additives contained in the plating solution. The additive is added so as to promote the plating formation more uniformly. For example, the additive is promoted inside the fine grooves or holes formed on the surface of the semiconductor wafer and other than the fine grooves or holes. The wafer surface contains a component that suppresses plating formation. By such a function of the additive, it becomes possible to fill the fine grooves and holes with the plating material without voids.

However, such an additive is consumed so much in the course of plating formation, and it is necessary to constantly supply a plating solution containing a new additive onto the surface of the wafer to be processed.
Therefore, the above-mentioned pump is increased in size.

With the recent improvement of additives, a premise for reducing the flow rate of supplying a plating solution containing a fresh additive onto the surface of a wafer to be processed is being provided. However, if the flow rate of the plating solution supplied to the surface of the wafer to be processed is reduced, a new problem that has never occurred until now occurs.

The plating solution always has an interface with air in the plating solution tank or the plating solution tank. For this reason, air is entrained at the interface of the plating solution, and a state in which gas bubbles are present in the plating solution is created. Among such gas bubbles, those with a large diameter that float on the surface of the plating solution within a relatively short time cause the gas bubbles to float while the plating solution is stored in the plating solution tank, and If the completed plating solution is supplied to the plating solution tank, the plating formation will not be affected.

However, those having a diameter small enough to float in the plating solution (fine bubbles) are supplied to the plating solution tank together with the plating solution and adhere to the surface of the wafer to be processed on which the plating is formed.

Even if fine bubbles adhere to the surface of the wafer to be processed in the plating solution, if the flow rate of the plating solution is high, they are successively replaced by other fine bubbles and averaged in terms of time. It does not affect the non-uniformity of plating formation.

However, if the flow rate of the plating solution supplied to the surface of the wafer to be processed becomes smaller than ever before, the fine bubbles once adhered to the surface of the wafer to be processed in the plating solution will remain as they are for a certain period of time or longer. Become. Then, microscopically, the conditions for forming the plating are different between the part where the fine bubbles happen to adhere and the part where the fine bubbles happen to not adhere.

Therefore, due to such non-uniformity of the plating forming conditions, the quality and thickness of the plating film formed on the surface of the wafer to be processed becomes uneven within the surface, and semiconductors to be manufactured, etc. There is a hindrance in ensuring the quality of.

The present invention has been made in consideration of such a situation, and a plating apparatus for plating an object to be processed,
In a method of manufacturing a semiconductor device including a step of plating an object to be processed, a plating processing apparatus capable of forming a high-quality plating while reducing a processing / manufacturing burden,
Another object of the present invention is to provide a method for manufacturing a semiconductor device.

[0021]

In order to solve the above problems, a plating apparatus according to the present invention contains a first and a second plating solution and is a conductive layer formed on a processing surface of an object to be processed. A plating solution tank for bringing the conductive layer into contact with the first plating solution to form a plating layer, and an anode provided in the plating solution tank and in contact with the second plating solution contained in the plating solution tank Electrodes, provided in the plating solution tank,
An electrolytic film for separating the first plating solution that contacts the conductive layer and the second plating solution that contacts the anode electrode, and first and second plating solutions to be supplied to the plating solution tank; A plating solution tank for storing first and second plating solutions discharged from the plating solution tank; and a first plating solution supplied from the plating solution tank to the plating solution tank and A first plating solution circulation path for discharging the first plating solution to a plating solution tank; and supplying the second plating solution from the plating solution tank to the plating solution tank and from the plating solution tank A second plating solution circulation path for discharging the second plating solution to a plating solution tank, and a gas in the first plating solution in a plating solution supply path of the first plating solution circulation path. Degas bubbles Characterized in that it has at least one care mechanism.

By providing a degassing mechanism in the plating solution supply path of the plating solution circulation path, fine bubbles of the plating solution supplied to the plating solution tank can be removed. That is, in the case where the plating solution tank is divided into the anode side and the cathode side (the side of the object to be processed) with the electrolytic membrane, by providing the degassing mechanism in the plating solution supply path of the plating solution circulation path on the cathode side, It is possible to remove fine bubbles adhering to the surface of the object to be processed. Therefore, the pump for supplying the plating solution can be downsized to reduce the burden of processing and manufacturing, and high-quality plating can be performed.

Further, a plating solution tank filled with the plating solution and contacting the conductive layer formed on the processed surface of the object to be processed with the plating solution to form a plating on the conductive layer, and a plating solution tank are supplied. A plating solution tank for storing a plating solution to be performed and a plating solution discharged from the plating solution tank, and supplying the plating solution from the plating solution tank to the plating solution tank and from the plating solution tank to the plating solution tank It has a plating solution circulation path for discharging the plating solution, and a degassing mechanism which is provided so as to be immersed in the plating solution in the plating solution tank and degasses gas bubbles in the plating solution in the plating solution tank. It is characterized by

That is, the degassing mechanism for removing fine bubbles is
It may be provided in the plating solution tank. By providing the plating solution tank with a degassing mechanism, the plating solution from which fine bubbles have been removed is supplied to the plating solution tank. Therefore, the pump for supplying the plating solution can be miniaturized to reduce the processing / manufacturing burden and to perform high-quality plating formation.

Here, in claim 1, the degassing mechanism is:
A pipe that allows a plating solution to be degassed to pass therethrough and has a gas-liquid separation function, an outer cylinder that secures a space between the pipe and airtightly surrounds the pipe, and is connected to the outer cylinder. And a pressure reducing mechanism for reducing the atmospheric pressure in the outer cylinder.

By decompressing the inside of the outer cylinder, fine bubbles contained in the plating liquid passing through the tube pass through in the thickness direction of the tube and are removed. As a material forming the tube, a material having a property that gas passes but liquid does not pass is used.

In the second aspect of the present invention, the demounting mechanism has a pipe having a gas-liquid separating function and a pressure reducing mechanism for reducing the pressure in the pipe.

By depressurizing the inside of the tube having a gas-liquid separating function immersed in the plating solution, fine bubbles contained in the plating solution pass through in the thickness direction of the tube and are removed.

Here, the gas bubbles to be degassed may have a diameter of 0.1 μm or less. This is because gas bubbles having such a size do not float on the surface of the liquid in a short time and float in the plating liquid.

Further, the method for manufacturing a semiconductor device according to the present invention uses a plating solution tank containing a first plating solution which comes into contact with the processing surface of the object to be processed and a second plating solution which comes into contact with the anode electrode. A method of manufacturing a semiconductor device, comprising a step of removing gas bubbles in the first plating solution,
A step of supplying the first plating solution from which the gas bubbles have been removed to the plating solution tank, a step of supplying the second plating solution to the plating solution tank, and a step of supplying the first and second plating solutions. And a step of performing a plating process on the object to be processed in a supplied plating tank.

According to this manufacturing method, it is possible to prevent fine bubbles from adhering to the surface of the object to be treated. Therefore, the pump for supplying the plating solution can be downsized to reduce the burden of processing and manufacturing, and high-quality plating can be performed.

Further, the method for manufacturing a semiconductor device according to the present invention comprises a step of removing gas bubbles having a diameter of 0.1 μm or less from a plating solution for plating an object to be processed, and a plating solution from which the gas bubbles have been removed. Is supplied to the plating solution tank for plating the object to be processed in an amount of 10 liters or less per minute, and the step of plating the object to be processed in the plating solution tank to which the plating solution is supplied. It is characterized by

According to this manufacturing method, it is possible to prevent fine bubbles from adhering to the surface of the object to be treated, especially when supplying an amount of 10 liters or less per minute. Therefore, the pump for supplying the plating solution can be downsized to reduce the burden of processing and manufacturing, and high-quality plating can be performed. This is because when the plating liquid is supplied at an amount of 10 liters / min or less, if gas bubbles adhere to the processing surface, they cannot be easily separated.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION A pump for feeding a plating solution is usually provided in a plating solution supply path, and a foreign material mainly generated from an anode electrode provided downstream of the pump is prevented from circulating together with the plating solution. And a filter.
In the practice of the present invention, the degassing mechanism may be provided at any position along this path. For example, upstream of the pump, downstream of the filter, intermediate between the pump and the filter. Further, a degassing mechanism may be provided so as to be built in the filter. Moreover, you may provide in multiple in these positions.

A degassing mechanism may also be provided in the plating solution supply path of the plating solution circulation path on the anode side. Further, it is possible to remove fine bubbles of the plating solution.

When the degassing mechanism is provided in the plating solution supply paths of both the cathode side and the anode side, the plating solution supply path may be provided at any position in this supply path.

Further, on the depressurizing side of the degassing mechanism, there may be provided a mechanism for separating a small amount of leaking liquid (that is, the plating liquid) into a gas and a liquid on the depressurizing side. It is possible to prevent the plating liquid from leaking to the outside.

Materials having the gas-liquid separation function of the degassing mechanism include polytetrafluoroethylene (PTFE), polyethylene, polycarbonate, etc., which are used as porous membranes, non-porous membranes, and composite membranes combining these.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram schematically showing the structure of a plating apparatus which is an embodiment of the present invention.

As shown in the figure, in the plating solution tank 11 filled with the plating solution, a mounting table 10 for placing the object 12 to be processed with its processing surface facing downward is immersed in the surface of the plating solution. The object 12 to be processed is mounted on the mounting table 10 from the outer periphery thereof.
The negative power supply for the plating process is supplied from the plating power source 14 through the conductor disposed in the.

A doughnut-shaped anode electrode 13 made of copper containing phosphorus, for example, is arranged near the bottom of the plating solution tank 11 and receives a positive side electric power supply from a plating power source 14.

A jet pipe 16 for jetting the plating solution toward the object 12 to be treated extends from the center of the bottom portion of the plating solution tank 11 to the upper part thereof, so that the plating process is constantly performed in a new plating solution. .

An ionization film 15 is provided above and below the jetting pipe 16 to divide the plating solution into upper and lower parts, and prevents foreign matter that is separated from the anode electrode 13 during plating from entering the cathode side and obstructing the plating formation.

On the upper part of the plating liquid tank 11, there is provided a liquid outlet 17 for discharging the plating liquid overflowing corresponding to the plating liquid ejected from the ejection pipe 16.

A liquid inlet 18 and a liquid outlet 19 for circulating the plating liquid on the anode side are provided at positions eccentric from the center of the bottom of the plating liquid tank 11 to maintain the uniformity of the plating liquid. Circulate the plating solution.

For circulation of the cathode side plating solution, the first plating solution 23 in the plating solution tank 20 is provided as a supply side.
A supply pipe for guiding the gas to the ejection pipe 16 is provided. The supply pipe has a pump 26 for adjusting the supply amount, an in-line filter 27 for filtering foreign substances in the plating liquid, and a degassing mechanism 28 for removing fine bubbles in the plating liquid. Is provided. On the discharge side, the first plating solution 23 in the plating solution tank 20 is supplied from the solution outlet 17.
A discharge pipe is provided toward.

In order to circulate the anode side plating solution, the second plating solution 22 in the plating solution tank 20 is used as a supply side.
A supply pipe that guides the liquid to the liquid inlet 18 is provided, and a pump 29 that adjusts the supply amount and an in-line filter 27 that filters foreign substances in the plating liquid are provided in the supply pipe. On the discharge side, a discharge pipe is provided from the liquid outlet 19 toward the second plating liquid 22 of the plating liquid tank 20.

As described above, the plating solution tank 20 contains the plating solution 23 for circulating the cathode-side plating solution,
The plating solution 22 for circulating the anode-side plating solution is separated by the partition wall 21 for the time being, but there is a separate circulation system for circulating and homogenizing these. For this circulation, a pump 24 for supplying the second plating solution 22 to the first plating solution 23 side and an in-line filter 25 on the downstream side of the pump 24 are provided. By this supply, the first plating liquid 23 overflows the partition wall 21 and flows into the second plating liquid 22 side. By such circulation of the first and second plating solutions 23, 22, at the same time, the bubbles generated in the first plating solution 23 are floated up, and the bubbles are not mixed particularly in the plating solution supply path on the cathode side. To do so.

In the plating apparatus having the above-described structure, the main causes of bubbles in the plating solution are:
This is a part where the plating solution and air form an interface, and more specifically, the first plating solution 2 in the plating solution tank 20.
3, the second plating liquid 22, and the liquid level of the plating liquid in the plating liquid tank 11.

Therefore, in the plating liquid tank 20, a sufficient amount of the plating liquid is stored, the bubbles are floated by the storage, and the plating liquid from which the bubbles have been sufficiently removed is used especially for circulation on the cathode side. .

By such a method, bubbles having a large diameter that float on the liquid surface in a relatively short time are removed, but fine bubbles are not removed because they float in the plating solution. It also removes such fine bubbles that remain without being removed.
In particular, this embodiment is designed so as not to reach the processing surface of the object to be processed 12.

For this reason, a deaeration mechanism 28 is provided immediately before the ejection pipe 16. The degassing mechanism 28 removes fine bubbles contained in the plating solution, and supplies such a plating solution to the processing surface of the object 12 to be processed. Therefore, fine bubbles do not adhere to the processing surface regardless of the supply speed.

Especially when the feeding speed is slow (eg 1 / min)
At 0 liters or less), if fine bubbles are present, they are not easily attached to the treated surface and are not easily replaced by new fine bubbles, so that the microscopically seen plating formation conditions are not uniform on the treated surface. Therefore, according to this embodiment, such a microscopic difference in the plating forming conditions does not occur, so that it is possible to prevent unevenness in the film thickness and film quality of the formed plating.

In this embodiment, the deaeration mechanism 28
Is provided on the downstream side of the in-line filter 27, but may be provided on the upstream side of the pump 26 or between the pump 26 and the in-line filter 27.

Regarding this arrangement position, one is that fine bubbles contained in the first plating solution 23 stored in the plating solution tank 20 are removed as early as possible and supplied to the plating solution tank 11. In terms of meaning, it is better to install it on the upstream side of the supply pipe. However, in this case, it is premised that the air is not entrained in the pump 26 or the in-line filter 27. If there is a concern about such entrainment of air, a portion near the ejection pipe 16 is preferable as shown in the figure.

Further, in the case where the supply pipe is long, etc., in order to secure a sufficient degassing effect, it may be provided at each of the above-mentioned installation positions. Further, a mechanism may be added to each of the in-line filter 27 and the pump 26 so as to have a deaeration function.

Further, the degassing mechanism may be provided in the supply pipe on the anode side. This is because the degassed anode-side plating solution circulates the degassed plating solution from the anode side to the cathode side. Even when it is provided in the supply pipe on the anode side, it can be provided downstream of the inline filter 30, upstream of the pump 29, and between the pump 29 and the inline filter 30, as described above.

In addition, as a plating processing apparatus, there is a plating processing apparatus in which a plurality of plating solution baths 11 are provided so that the plating can be processed in parallel in order to systematize the processing and improve the productivity. In such a case, a configuration in which a plurality of plating solution tanks 11 are provided and the plating solution tank 20 is single is used. At this time, a degassing mechanism can be provided in the supply pipe from the single plating solution tank to each of the plurality of plating solution tanks.

Next, the deaeration mechanism 2 described in the above embodiment.
A specific example of No. 8 will be described with reference to FIG. This figure shows
It is a figure which shows the structural example of a deaeration mechanism.

The degassing mechanism 28 has a cylindrical hermetic container 51 having an inlet 53 for introducing the plating solution and an outlet 54 for delivering the plating solution. The exhaust pipe 5 is provided on the side wall of the closed container 51.
5 is connected, and the exhaust pipe 55 is connected to the pressure reducing mechanism 56.

From the inlet 53 to the outlet 54,
A plurality of pipe members 52 having a gas-liquid separation function are arranged, and the gas-liquid separation function of the pipe member 52 can be realized by using PTEF, for example.

When the pressure-reducing mechanism 56 is operated to evacuate the inside of the closed container 51, the plating liquid flowing through the pipe member 52 is degassed through the wall of the pipe member 52, and the contained fine bubbles are removed. .

Regarding the diameter of the fine bubbles to be degassed, the larger the finer bubbles are, the smaller the plating solution supply rate is. This is because as the plating solution supply rate decreases, larger bubbles adhere to the processing surface. The range of such fine bubbles to be removed is set by selecting a gas-liquid separation material, or selecting its microscopic structure such as a pore size, and designing the pressure inside the closed container 51 by decompressing the decompression mechanism 56. You can

In any case, the fine bubbles to be deaerated should be those having a diameter of 0.1 μm or less. This is because fine bubbles at this level are slow to float on the liquid surface and have high floating properties in relation to the physical properties such as the viscosity and surface tension of the plating liquid.

Further, in order to perform degassing more efficiently, the pressure reduction by the pressure reducing mechanism 56 is preferably large, and for that purpose, for example, -933 hPa (-700 mmH) on the atmospheric pressure basis is used.
g, an absolute pressure of 80 hPa, a pressure lower than about 60 mmHg) can be used.

When degassing is performed at such a low pressure, the plating solution may mix on the reduced pressure side. The plating solution is acidic and corrosive, and it is not preferable to release it to the outside. Therefore, the decompression mechanism 56 may be provided with a mechanism for trapping the mixed plating liquid. Such a mechanism will be described later.

Next, an embodiment different from the embodiment shown in FIG. 1 will be described with reference to FIG. This figure is a diagram schematically showing the configuration of a plating apparatus which is an embodiment of the present invention, and the components already described are given the same numbers and their explanations are omitted.

The degassing of this embodiment is performed by the plating liquid tank 2
Degassing members 41, 42 provided at 0 and the degassing member 41,
Valves 44, 45 connected to 42 and valves 44, 4
5 and a pressure reducing mechanism 43 connected to each other.

The degassing members 41 and 42 are respectively used as the second plating liquid 22 and the first plating liquid 2 in the plating liquid tank 20.
It is dipped in the storage part of No. 3 in a spiral shape, for example. As a result, the contact surface area with the plating solution can be increased and efficient degassing can be achieved.

The degassing members 41 and 42 are the same as those described above for P.
It is possible to use a TEF or the like which is closed at one end and is tubular. FIG. 5 is a vertical cross-sectional view of this partial structure. That is, a hollow 72 is secured inside the pipe 71 having a gas-liquid separating function such as PTEF, and the hollow maintaining member 73 is spirally formed, for example, in order to prevent the pipe 71 from being crushed by depressurizing the hollow 72. It is provided. With such a structure, the deaeration members 41, 42
Will have flexibility as a whole, and can have various shapes other than the spiral shape shown in FIG. 2 in order to increase the contact area with the plating solution. For example, a shape in which a large number of tubes are reciprocated such that the tubes are arranged in parallel is used.

To operate the deaeration function, the valve 44,
45 is opened and the decompression mechanism 43 causes the deaeration members 41, 42.
The inner hollow 72 is decompressed. As a result, when the inside of the hollow 72 is evacuated, the plating solution existing in the plating solution tank 20 is degassed via the walls of the degassing members 41 and 42, and the contained fine bubbles are removed. Therefore, the plating liquid supplied from the cathode side supply path to the processing surface via the ejection pipe 16 does not have fine bubbles, and there is no microscopic difference in the plating forming conditions on the processing surface. Thick,
It is possible to prevent uneven film quality.

Also in this case, the range of the fine bubbles to be removed is set by selecting the gas-liquid separating material or the microscopic structure such as the pore size, and the depressurizing mechanism 43 and the valve 4.
This can be done by designing the pressure inside the deaerating members 41 and 42 by reducing the pressure to 4, 45.

The size of the fine bubbles to be degassed can be considered in the same manner as in the embodiment shown in FIG.

Further, the pressure reducing mechanism 43 and the valves 44 and 4
The decompression by 5 and 5 can be considered in the same manner as the decompression by the decompression mechanism 56.

Next, the pressure reducing mechanism 56 or the pressure reducing mechanism 43.
A depressurizing mechanism having a plating liquid trapping function that can be used as the above will be described with reference to FIG. This figure is a diagram showing a configuration of a pressure reducing mechanism having a plating liquid trap function.

The depressurizing mechanisms 56, 43 can be, in the simplest form, pumps having a function of vacuuming. However, when the set pressure for efficient degassing and the result of selection of the material having the gas-liquid separation function and its fine structure are actually applied to the plating apparatus, the plating solution may be mixed on the reduced pressure side. is there.

The plating solution is acidic and corrosive, and it is not preferable to release it to the outside. Therefore, the pressure reducing mechanism 56, 4
In addition to 3, a mechanism for trapping the mixed plating solution is added.

To explain the structure, a trap tank 61, which is connected to the gas side of the degassing mechanism and accommodates the plating liquid leaked during the degassing process, and a stop valve 6 in the trap tank 61.
3, a solenoid valve 64 connected via 3 for adjusting the amount of pressure reduction, an ejector 65 connected to the solenoid valve 64 for reducing the pressure on the gas side of the degassing mechanism, a regulator 68 for adjusting the amount of air flowing through the ejector 65, and a solenoid valve. 66, as well as a gauge 67 indicating the pressure downstream of the regulator 68. Further, the trap tank 61 has a liquid level sensor 62 for detecting the liquid level.

To perform the deaeration process, the solenoid valve 6
4 is opened, the regulator 68 and the solenoid valve 66 are set in a predetermined state while observing the gauge 67, and the ejector 65 is set.
To operate. As a result, the pressure is reduced by the solenoid valve 6
4, through the stop valve 63 and the trap tank 61 to the gas side of the degassing mechanism.

From the gas side of the degassing mechanism, the degassed gas and the leaked plating solution are transferred to the trap tank 61. Of these, only gas is taken out by the ejector 65 via the stop valve 63 and the solenoid valve 64. The plating liquid caused by the leakage is trap tank 61
Housed in. The liquid level sensor 62 detects a predetermined upper limit and a lower limit, and when the upper limit is reached, the plating liquid is discharged to the lower limit.

Next, an embodiment of the semiconductor device manufacturing method of the present invention will be described with reference to FIG. The figure is a flow chart for explaining the method for manufacturing a semiconductor device of the present invention.

The method of manufacturing a semiconductor device according to this flowchart can be carried out in the plating apparatus shown in FIG. 1 or 2 which has already been described. That is, FIG.
As shown in (1), first, fine bubbles are removed from the plating solution (step 81). This is directly performed by the degassing mechanism 28 in FIG. 1 and by the degassing members 41 and 42 in FIG.

Next, the plating solution is supplied to the plating solution tank (step 82). This corresponds to the fact that in FIG. 1, the plating solution that has passed through the degassing mechanism 28 is supplied from the ejection pipe 16 to the processing surface of the object to be processed 12 into the plating solution tank 11.
Then, the plating liquid degassed by the degassing members 41 and 42 of the plating liquid tank 20 enters the plating liquid tank 11 via the pump 29 and the in-line filter 30, or the pump 2
6, corresponding to being supplied to the plating liquid tank 11 via the in-line filter 27.

Next, plating is formed in the plating liquid tank 11 (step 83). This plating is performed in the plating solution from which the fine bubbles have been removed as described above. Therefore, even if the amount of the plating solution supplied is small, the state in which the fine bubbles adhere to the treated surface is not created, and thus the plating is performed. The film quality and film thickness of can be made more uniform. Further, since the amount of plating liquid supplied to the processing surface can be reduced even if the film quality and film thickness of such plating are made uniform, the pump for ejecting the plating liquid can be downsized and the plating process can be performed. It is possible to reduce the burden for manufacturing and device manufacturing.

[0086]

As described in detail above, according to the present invention,
By providing a degassing mechanism in the plating solution supply path of the plating solution circulation path, fine bubbles of the plating solution supplied to the plating solution tank are removed, and even if the amount of plating solution supplied to the plating solution tank is reduced No fine bubbles adhere to the body surface. As a result, the pump for supplying the plating solution can be downsized to reduce the processing / manufacturing burden, and high-quality plating can be performed without being affected by fine bubbles.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a configuration of a plating processing apparatus that is an embodiment of the present invention.

FIG. 2 is a diagram schematically showing a configuration of a plating apparatus which is an embodiment of the present invention different from the above.

FIG. 3 is a diagram showing a configuration example of a degassing mechanism 28.

FIG. 4 is a diagram showing a configuration of a pressure reducing mechanism having a plating liquid trap function.

FIG. 5 is a vertical cross-sectional view schematically showing the structure of a part of degassing members 41 and 42.

FIG. 6 is a flowchart illustrating a method for manufacturing a semiconductor device according to the present invention.

[Explanation of symbols]

10 ... Stand 11 ... Plating liquid tank 12 ... Object to be processed 13 ... Anode electrode 14 ... Plating power supply 15 ... Electrolytic membrane 16 ... Spout pipe 17 ... Liquid outlet 18 ... Liquid inlet 19 ... Liquid outlet 20 ... Plating liquid tank 21 ... Partition 22 ... Second plating solution 23 ... First plating liquid 24, 26, 29 ... Pump 25, 27, 30 ... In-line filter 28 ... Degassing mechanism 41, 42 ... Degassing member 43 ... Decompression mechanism 44, 45 ... Valve 51 ... Airtight container 52 ... Pipe member 53 ... Inlet 54 ... Delivery port 55 ... Exhaust pipe 56 ... Decompression mechanism 61 ... Trap tank 62 ... Liquid level sensor 63 ... Stop valve 64 ... Solenoid valve 65 ... Ejector 66 ... Solenoid valve 67 ... Gauge 68 ... Regulator 71 ... tube 72 ... Hollow 73 ... Hollow maintenance member

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Norihiko Tsuji             TBS release, 5-3-6 Akasaka, Minato-ku, Tokyo             Sending Center Tokyo Electron Limited F-term (reference) 4M104 BB04 DD52

Claims (7)

[Claims] 1. A plating solution containing a first and a second plating solution and contacting a conductive layer formed on a processing surface of an object to be processed with the first plating solution to form a plating on the conductive layer. A tank, an anode electrode provided in the plating solution tank and in contact with the second plating solution contained in the plating solution tank, and a first electrode provided in the plating solution tank and in contact with the conductive layer The second liquid contacting the plating liquid and the anode electrode
And a plating solution tank for storing the first and second plating solutions to be supplied to the plating solution tank and the first and second plating solutions discharged from the plating solution tank. And a first plating solution circulation path for supplying the first plating solution from the plating solution tank to the plating solution tank and discharging the first plating solution from the plating solution tank to the plating solution tank. And a second plating solution circulation path for supplying the second plating solution from the plating solution tank to the plating solution tank and discharging the second plating solution from the plating solution tank to the plating solution tank And a plating solution supply path of the first plating solution circulation path having at least one degassing mechanism for degassing gas bubbles in the first plating solution. 2. A plating solution tank filled with a plating solution and contacting a conductive layer formed on a processing surface of an object to be processed with the plating solution to form a plating on the conductive layer, and supplying to the plating solution tank. A plating solution tank for storing a plating solution to be performed and a plating solution discharged from the plating solution tank; and a plating solution tank for supplying the plating solution to the plating solution tank from the plating solution tank and from the plating solution tank to the plating solution tank. It has a plating liquid circulation path for discharging the plating liquid, and a degassing mechanism which is provided so as to be immersed in the plating liquid in the plating liquid tank and which degasses gas bubbles in the plating liquid in the plating liquid tank. A plating treatment device characterized in that 3. The degassing mechanism is an outer cylinder that encloses the pipe in a gastight manner by ensuring a space between the pipe and a pipe that allows a plating liquid to be degassed to pass therethrough and has a gas-liquid separation function. The plating processing apparatus according to claim 1, further comprising: a pressure reducing mechanism that is connected to the outer cylinder and that reduces a pressure in the outer cylinder. 4. The plating processing apparatus according to claim 2, wherein the degassing mechanism includes a tube having a gas-liquid separation function and a depressurizing mechanism that depressurizes the atmospheric pressure in the tube. 5. The gas bubble to be degassed has a diameter of 0.
The plating processing apparatus according to claim 1, wherein the plating processing apparatus has a thickness of 1 μm or less. 6. A method of manufacturing a semiconductor device, comprising: a plating liquid tank containing a first plating liquid that contacts a processing surface of an object to be processed and a second plating liquid that contacts an anode electrode; Removing the gas bubbles in the first plating solution, supplying the first plating solution from which the gas bubbles have been removed to the plating solution tank, and supplying the second plating solution to the plating solution tank A method of manufacturing a semiconductor device, comprising: a step; and a step of performing a plating process on the object to be processed in a plating tank to which the first and second plating solutions are supplied. 7. A step of removing gas bubbles having a diameter of 0.1 μm or less from a plating solution for plating an object to be processed, and plating the object to be processed with the plating solution from which the gas bubbles have been removed. A method for manufacturing a semiconductor device, comprising: a step of supplying an amount of 10 liters or less per minute to a liquid tank; and a step of plating the object to be processed in a plating liquid tank to which the plating solution is supplied.