JP4014827B2 - Plating equipment - Google Patents

Abstract

A plating processing device is so arranged that at least a part of a portion touching plating liquid is made of a material whose change rate of surface roughness in response to a removing agent is lower than resin when the material and the resin are measured in the same conditions. For example, a storage tank (1), a plating processing tank (2), a buffer tank (3), and a pipe (9) are made of hard glass and quartz glass. With this, it is possible to prevent a plating material from being deposited as foreign body on wall surfaces of the plating processing tank, etc.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plating apparatus used in a manufacturing apparatus such as a semiconductor integrated circuit.
[0002]
[Prior art]
Electronic devices such as portable information terminals are becoming smaller and lighter, and in response, semiconductor integrated circuits incorporated in these devices are also required to be smaller and lighter and more densely mounted.
[0003]
As an effective method for achieving miniaturization and high-density mounting of a semiconductor integrated circuit or the like (hereinafter referred to as a semiconductor device), a so-called bump is formed by gold (Au) using a plating technique at a predetermined position on the surface of the semiconductor device. There is a method in which an electrode is formed and a semiconductor device is directly mounted on a mounting substrate using the bump electrode, which is widely used.
[0004]
FIG. 3 shows an overview of a conventionally used plating apparatus.
[0005]
In FIG. 3, 51 is a storage tank, 52 is a plating tank, 53 is a buffer tank, 54 is a circulation pump, 55 is a float type flow meter, 56 is a filter, 57 is a heat exchange unit, and 58 is piping. . Resin-based materials are used as materials for the storage tank 51, the plating tank 52, the buffer tank 53, the heat exchange unit 57, and the pipe 58.
[0006]
The plating solution pressurized by the circulation pump 54 flows into the storage tank 51. The plating solution injected into the storage tank 51 is adjusted in flow rate in the storage tank 51 and flows into the next plating treatment tank 52 at a predetermined flow rate (liquid weight). Next, the plating solution flows from the outlet of the plating tank 52 into the buffer tank 53, accelerated again by the circulation pump 54, and flows into the storage tank 51.
[0007]
When circulating the plating solution, bubbles may be generated in the plating solution due to cavitation of the circulation pump. When these bubbles adhere to the surface of the substrate, the growth of the plating is hindered, and in the worst case, abnormal plating (abnormal plating thickness or defective plating shape) occurs. In order to remove the bubbles, for example, the plating solution pressurized by the circulation pump is once flowed into the storage tank, and after the bubbles in the solution are released into the atmosphere, the plating solution is not pressurized, It flows into the plating tank 52 by its own weight.
[0008]
When plating, the control of the plating solution flow rate and the plating solution temperature are also important factors for controlling the metal deposition rate and the uniformity of the deposition rate on the substrate, that is, for controlling the plating thickness. .
[0009]
For measuring the flow rate of the plating solution, a float type flow meter 55 is provided in the middle of the piping from the storage tank 51 to the plating treatment tank 52 to control the flow rate. The temperature control of the plating solution is performed by immersing a heat exchange unit 57 (indirectly adjusting the temperature (temperature adjustment) by circulating hot water in a resin-bound tube) in the buffer tank 53.
[0010]
When plating is performed, the plating metal may be deposited on a plating solution circulation pipe, a circulation pump, or a plating tank itself other than a predetermined position on the substrate due to the property of the plating solution. A part of the deposited metal other than the predetermined position peels off from the deposited position and floats as a foreign substance in the plating solution, and moves in the plating apparatus according to the flow of the plating solution. If this foreign matter adheres to the surface of the substrate, it causes it to cause abnormal plating (abnormal plating thickness or defective plating shape) in the worst case. In order to remove this foreign matter, for example, a filter 56 is provided after the circulation pump. Further, as shown in FIG. 3, a filter 56 is also provided immediately before the plating tank 52.
[0011]
Foreign matters floating in the plating solution are removed by using a filter, but precipitates deposited and fixed on the inner wall of a plating tank or the like cannot be removed by the filter. Since these deposits may cause defects such as clogging of pipes and an increase in the number of foreign substances, the pipes and plating tanks should be periodically cleaned using halogen-based chemicals (such as aqua regia and iodine). Yes.
[0012]
[Problems to be solved by the invention]
As described above, due to the nature of the plating solution, the metal deposits on portions other than the desired position, such as the inner wall of the plating tank and the inner wall of the pipe, where the plating solution contacts. Most of these metals are deposited and fixed on the inner wall surface of a plating tank or the like, and are periodically cleaned and removed with a halogen-based chemical solution.
[0013]
Conventionally, there is a problem that it is difficult to easily and effectively suppress the precipitation of a plating substance as a foreign material that occurs in the plating process.
[0014]
[Means for Solving the Problems]
In order to solve the above-described problems, the plating apparatus of the present invention supplies a plating solution containing a plating substance, and contacts the plating object with the plating solution to plate the plating object, and at an undesired position. In a plating apparatus that removes a plating substance with a removing agent when the plating substance is deposited on the surface, at least a part of the portion that comes into contact with the plating solution is measured under the same conditions when the removing agent is applied. It is characterized in that it is formed of a material whose surface roughness change rate is sometimes lower than that of resin.
[0015]
With the above configuration, at least a part of the portion that comes into contact with the plating solution is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied.
[0016]
Therefore, when a plating substance is deposited at an undesired position after plating, the portion formed with the above-mentioned material when the removing agent is applied and in contact with the plating solution is made of resin. The surface is less likely to be rough than when formed. Since the surface is difficult to be roughened, it is possible to suppress the precipitation of the plating substance from being accelerated by the unevenness corresponding to the roughness.
[0017]
Therefore, it is possible to easily and effectively suppress the precipitation of the plating substance as a foreign matter, which occurs in the plating process.
[0018]
The plating apparatus of the present invention further includes a plating treatment tank for bringing the object to be plated into contact with the plating solution in addition to the above-described configuration, and the wall surface of the plating treatment tank is the same when the removing agent is applied. It is characterized in that it is formed of a material whose surface roughness change rate is lower than that of resin when measured under conditions.
[0019]
With the above configuration, the wall surface of the plating treatment tank is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied. Therefore, in addition to the effects of the above-described configuration, it is possible to more easily and effectively suppress the precipitation of the plating substance as a foreign matter that occurs in the plating process.
[0020]
In addition to the above-described configuration, the plating apparatus of the present invention includes a plating tank for bringing a plating object into contact with a plating solution, and a pipe for a plating tank that carries the plating solution to the plating tank. The wall surface of the plating tank pipe is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied.
[0021]
With the above configuration, the wall surface of the plating tank pipe is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied. Therefore, in addition to the effects of the above-described configuration, it is possible to more easily and effectively suppress the precipitation of the plating substance as a foreign matter that occurs in the plating process.
[0022]
In addition to the above configuration, the plating apparatus of the present invention includes a plating tank for bringing a plating object into contact with a plating solution, and a storage tank for storing a plating solution to be put into the plating tank, and the storage The wall surface of the tank is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied.
[0023]
With the above configuration, the wall surface of the storage tank is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied. Therefore, in addition to the effects of the above-described configuration, it is possible to more easily and effectively suppress the precipitation of the plating substance as a foreign matter that occurs in the plating process.
[0024]
In addition to the above-described configuration, the plating apparatus of the present invention is characterized by including a heating tank in which the storage tank is placed and the plating solution in the storage tank is heated by heat conduction.
[0025]
With the above configuration, the plating solution in the storage tank is heated by heat conduction. Therefore, it is not necessary to use a member that directly contacts the plating solution as a heat exchange unit for temperature adjustment. Therefore, in addition to the effects of the above-described configuration, it is possible to more easily and effectively suppress the precipitation of the plating substance as a foreign matter that occurs in the plating process.
[0026]
In addition to the above-described configuration, the plating apparatus of the present invention includes a plating tank for bringing a plating object into contact with a plating solution, and a pipe for a plating tank that carries the plating solution to the plating tank. An ultrasonic flow meter is disposed in a part of the plating tank pipe, and the wall surface of the plating treatment pipe in which the ultrasonic flow meter is disposed removes the removing agent. It is characterized in that it is formed of a material whose surface roughness change rate is lower than that of resin when measured under the same conditions.
[0027]
With the above configuration, the wall surface of the portion where the ultrasonic flowmeter is arranged in the plating treatment pipe is changed in surface roughness when measured under the same conditions when the removing agent is applied. It is formed of a material whose rate is lower than that of the resin. The ultrasonic flow meter is disposed at a position where it does not come into contact with the plating solution, and an ultrasonic signal is applied to the plating solution passing through the plating treatment pipe and the signal reflected from the plating solution is used. The flow rate of the plating solution can be measured. Therefore, in addition to the effects of the above-described configuration, it is possible to more easily and effectively suppress the precipitation of the plating substance as a foreign matter that occurs in the plating process.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
One embodiment of the present invention will be described with reference to FIGS. 1 and 2 as follows.
[0029]
Conventionally, a plating apparatus has been made using a resin-based material from a plating tank to piping.
[0030]
It has been found that the surface roughness of these resins increases with repeated washing with a halogen-based chemical solution (removal agent). The result is shown in FIG.
[0031]
In PVDF resin (Poly vinylidene fluoride) and PFA resin (Tetrafluoroethylene PerFluoroAlkylvinylether copolymer) used in plating tanks and storage tanks, the surface roughness (Ra: center line average roughness) In one week, the roughness increases by 70% to 158% compared to the initial value.
[0032]
With this change in surface roughness (increase in surface roughness), the activity of the irregularities formed on the surface changes, which becomes the nucleus and accelerates the deposition of the metal that is the plating substance Conceivable.
[0033]
On the other hand, in the case of hard glass and quartz glass (hereinafter referred to as glass) shown in FIG. 2, even when immersed in the same iodine solution, the change in surface roughness is 0% to 10%. And very few. Since it is impossible to completely prevent the deposition of metal to a place other than a predetermined position on the substrate (the part to be plated), periodic cleaning with a halogen-based chemical is inevitable. It is necessary to use a material that does not roughen the inner wall surface (the surface in contact with the plating solution) of the plating apparatus even if the cleaning with the chemical solution is repeated.
[0034]
The thickness of the plating needs to be uniform on the substrate to be plated. For this purpose, the flow control of the plating solution and the temperature control of the plating solution are also important factors as described above.
[0035]
Conventionally, a float type flow meter is used for measuring the flow rate. In this type of flow meter, the float (float) is floated and digitized, and the float itself becomes a factor that hinders the liquid flow. In addition, the piping for installing the flow meter is complicated, which increases the liquid contact area between the plating solution and the pipe (the area in contact with the liquid), and the metal inside the flow meter and the bent part of the pipe Is likely to precipitate, and also occurs in the float itself. Therefore, there is a possibility that stable and accurate measurement of the flow rate may not be possible due to the precipitate accumulated with the use time.
[0036]
As a method for measuring the flow rate of the chemical solution, there is a method using ultrasonic waves that can be performed without contact with the solution. An ultrasonic signal is applied to the fluid in the pipe, the transmission signal is read, and the flow velocity and flow rate are accurately measured. However, since the inner wall surface of the pipe becomes rough and the metal is deposited on the resin pipe, the transmission signal cannot be accurately transmitted and received, and cannot be used in the plating apparatus.
[0037]
The temperature control of the plating solution uses a heat exchange unit in which resin tubes are bundled in the buffer tank. However, the resin has poor thermal conductivity, and the liquid contact area must be increased to perform desired heat exchange. There is a need to. Therefore, in combination with the structure of the heat exchanger, the metal as the plating substance is likely to be deposited.
[0038]
Although it is desirable to control the temperature of the plating solution immediately before the plating tank, the conventional plating apparatus uses a resin heat exchange unit, so that metal is likely to deposit. Therefore, the temperature is controlled in a buffer tank, pressurized by a circulation pump, passed through a filter, and the plating solution is injected into the storage tank. As a result, the piping becomes long and a temperature drop occurs, making accurate temperature control difficult. Moreover, it will also lead to the further metal precipitation accompanying the increase in a liquid contact area.
[0039]
In the conventional plating apparatus, a filter 56 is also provided immediately before the plating tank 52 shown in FIG. This is provided in order to remove metal foreign matter deposited in the storage tank 51, the flow meter 55, and the piping from the storage tank 51 to the plating treatment tank 52. In order to remove foreign substances with a filter, it is necessary to apply a predetermined pressure to the chemical solution, but a pressurizing pump cannot be installed between the storage tank 51 and the plating tank 52 to prevent cavitation. It is necessary to pressurize with the drop of the chemical (self-weight). In order to obtain a desired pressure, it is necessary to install the storage tank 51 at an appropriate height and replace the filter depending on the condition of clogging of the filter (flow rate drop). For this reason, maintenance time and cost may increase.
[0040]
In order to prevent the deposition of metal such as gold (plating substance) other than a predetermined position on the substrate (the part to be plated of the plating target), the wetted area of the part in contact with the plating solution of the plating apparatus is minimized. In addition, it has been found that it is effective to make a plating apparatus using a material that does not change the roughness of the inner wall surface even when periodic cleaning with a cleaning agent such as a halogen-based chemical solution is performed. According to this, the generation of foreign matter in the plating apparatus can be greatly suppressed, the number of filters conventionally required for removing the foreign matter can be reduced, and maintenance time and costs associated with this replacement can be suppressed. It becomes.
[0041]
The outline of the process for forming gold (Au) bump electrodes on semiconductor integrated circuits will be described later. As already mentioned, pipes and plating tanks are regularly used with halogen-based chemicals (such as aqua regia and iodine). Must be cleaned.
[0042]
As already explained, FIG. 2 shows the rate of change in the surface roughness of the resin-based material and the glass-based material used in the plating apparatus when washed with a halogen-based chemical solution. As for the roughness (initial value) of the resin-based material and the glass-based material, there is no significant difference in the surface roughness in the pipe, but when immersed in a chemical solution (iodine) for one week, The surface roughness of the resin-based material changes very greatly at a rate of change of 70 to 158% with respect to the initial value. On the other hand, in the case of glass-based materials, it can be seen that the rate of change is remarkably small, 0 to 10%. The smaller the surface roughness change rate, the better.
[0043]
When the surface roughness change rate is high, that is, when the unevenness of the inner wall increases, the metal tends to deposit on the inner wall of each tank or pipe using it as the core, so each time cleaning with chemicals or several times of cleaning It is necessary to change each tank and piping every time.
[0044]
In the present embodiment, each part of the plating apparatus is configured by using glass as a material that does not cause roughening of the inner wall surface even when the cleaning with a halogen-based chemical solution is repeated. For this reason, the metal which precipitates on an inner wall surface can be suppressed.
[0045]
Since glass has a higher thermal conductivity than resin, the storage tank is made of glass, and the temperature of the plating solution is controlled by immersing the storage tank in the heating tank. As a result, a heat exchange unit is not required, the contact area with the plating solution is greatly reduced, and the temperature of the plating solution can be controlled in a place closer to the plating bath, thus stabilizing the processing temperature. Can be achieved.
[0046]
Since the storage tank, plating tank, and the piping between them are all made of glass-based material, it is possible to prevent metal deposition between them, so no filter is required between the storage tank and the plating tank. It is possible to reduce maintenance costs and maintenance time such as periodic filter replacement. Furthermore, the drop between the storage tank and the plating treatment tank may be provided with a drop necessary for the plating solution to flow, and the plating apparatus can be made compact.
[0047]
In addition, by changing the pipe to glass, it is possible to introduce an ultrasonic flowmeter that can measure the flow rate without contact with the liquid by suppressing the deposition of metal on the inner wall surface of the pipe, and the pipe has a simple structure. It is also possible to do.
[0048]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings for a plating apparatus used in a manufacturing process of a semiconductor integrated circuit.
[0049]
The chemical solution used in the following description is basically the same as the chemical solution and use conditions used in the production of a normal semiconductor integrated circuit, and detailed description thereof is omitted unless otherwise specified.
[0050]
First, a method for manufacturing a semiconductor integrated circuit using the plating apparatus according to the present embodiment, that is, a bump electrode forming process by gold (Au) plating on a semiconductor substrate will be described.
[0051]
The semiconductor substrate used as the substrate to be plated (plating target object) in the present embodiment is formed by incorporating a plurality of semiconductor integrated circuits, and is produced by the following steps.
[0052]
On the entire surface of a semiconductor substrate incorporating a semiconductor integrated circuit, for example, a silicon wafer having a diameter of 8 inches (about 200 mm), SiO 2 ₂ A predetermined thickness of the insulating film is deposited using a photolithographic technique and an insulating film etching technique.
[0053]
Next, a metal thin film such as Al—Si is deposited to a thickness of about 1 μm on the entire surface of the wafer, and a pad electrode serving as an input / output terminal is formed using a photolithographic technique and a metal thin film etching technique. Here, the size of the pad electrode was about 60 μm × 110 μm. At this time, it is assumed that interconnections of elements such as transistors incorporated on the wafer surface are formed at the same time.
[0054]
Next, an insulating film such as a SiN film is deposited to a thickness of about 0.6 μm as a surface protective film on the entire surface of the wafer, and a predetermined surface protective film is formed by a known method such as a photolithographic technique and an insulating film etching technique. The position is opened and the pad electrode is exposed. The size of the opening of the surface protective film is, for example, about 30 μm × 80 μm.
[0055]
Thereafter, for example, about 0.2 μm of TiW and 2 μm of Au are deposited as barrier metals, and then a mask for plating is formed using a photoresist. Using this mask, gold (Au) having a thickness of about 18 μm is deposited above the pad electrode by a known plating technique to form a bump electrode. The size of the bump electrode is, for example, about 30 μm × 80 μm as described above. More details are as follows.
[0056]
That is, a metal thin film is deposited on the entire surface of the wafer to a predetermined thickness. This metal thin film serves as a so-called current film when performing electrolytic plating while preventing the reaction between Au as a bump electrode and Al or Al alloy as the material of the pad electrode. Called. The underlying metal may be a single-layer metal thin film. However, from the viewpoint of preventing reaction between Au and Al or an Al alloy as described above, or from other viewpoints, a laminated film of a plurality of metals is usually used. It has been. As the base metal, TiW was deposited to about 0.2 μm in the lower layer, and Au was deposited to 0.2 μm in the upper layer.
[0057]
Next, a photoresist is applied to the entire surface of the wafer, and the photoresist on a predetermined position on the wafer, that is, above the opening of the surface protective film, is removed using a photolithographic technique.
[0058]
Through the above steps, the semiconductor substrate 4 to be a substrate to be plated in the next plating step is formed. The photoresist remaining on the wafer serves as a mask in the plating process, and the plated metal is deposited in the opening of the photoresist.
[0059]
Furthermore, a plating process for forming bump electrodes on the semiconductor substrate by Au plating will be described. The plating apparatus according to the present embodiment is an apparatus that performs this plating process.
[0060]
First, the cathode electrode of the plating apparatus is connected to a predetermined position of the base metal deposited on the wafer of the semiconductor substrate. Then, the semiconductor substrate and an anode electrode (not shown) face each other substantially in parallel, and are immersed in a plating solution filled in the plating tank 2. A predetermined voltage is applied between the semiconductor substrate and the anode electrode by a power source, and the plating metal is deposited at a predetermined position of the semiconductor substrate, that is, at the opening of the photoresist by electrolytic plating.
[0061]
What is necessary is just to set suitably the voltage applied between a semiconductor substrate and an anode electrode from the magnitude | size of a semiconductor substrate, a plating speed, etc. FIG.
[0062]
In the semiconductor substrate where the formation of the bump electrode by the plating process is completed, the photoresist is removed, and further, the unnecessary portion of the base metal is removed using the bump electrode itself as a mask. Thereafter, the semiconductor integrated circuit is completed through a predetermined process.
[0063]
Next, details of the plating apparatus according to the present embodiment will be described.
[0064]
FIG. 1 is a schematic diagram showing a configuration of a plating apparatus according to the present embodiment.
[0065]
In FIG. 1, 1 is a storage tank, 2 is a plating tank, 3 is a buffer tank, 4 is a circulation pump, 6 is a filter, 8 is piping (resin piping), 9 is piping (glass piping), 10 is a heating tank, Reference numeral 11 denotes an ultrasonic flow meter (liquid non-contact (non-liquid contact) type).
[0066]
Regarding the size of each tank, the storage tank 1 is about 400 mm (length) x 100 mm (width) x 300 mm (height), the plating tank 2 is about 300 mm x 100 mm x 300 mm, and the buffer tank 3 is about 700 mm x The thing of 500 mm x 200 mm was used. Moreover, the heating tank 10 should just have a sufficient bottom area and height for the storage tank 1 to enter.
[0067]
In the plating apparatus according to the present embodiment shown in FIG. 1, the storage tank 1, the plating tank 2, and the buffer tank 3 are made of glass, that is, hard glass or quartz glass, and from the filter 6. The pipe 9 to the storage tank 1 and the pipe 9 from the storage tank 1 to the plating tank 2 (plating tank pipe) 9 are also made of glass.
[0068]
Since the filter 6 to the plating tank 2 are made of glass, the deposition of metal on the tank and the inner wall surface of the pipe during this period is extremely small.
[0069]
Resin piping is used between the plating tank 2 and the filter 6. Since resin piping is used, metal is likely to deposit on the inner wall of the piping. However, metal foreign matter deposited during this time can be prevented from flowing into the storage tank 1 by providing a filter 6.
[0070]
The buffer tank 3 may be made of resin, but since the liquid contact area with the plating solution is increased, the amount of deposited metal is also increased, and the filter 6 is quickly clogged. Therefore, it is desirable that the buffer tank 3 is also made of glass.
[0071]
By making the pipe 9 from the storage tank 1 to the plating tank 2 made of glass, the amount of metal deposited on the inner wall surface is very small, and therefore a flow meter using ultrasonic waves can be used. Unlike conventional float type flowmeters, the piping between them is very simple, coupled with the use of glass, there is little metal deposition between them, resulting in the conventional plating. It is possible to omit the filter immediately before the plating tank that was necessary in the processing apparatus. In the plating apparatus according to the present embodiment, the number of filters can be reduced to about one-fifth compared with the apparatus according to the prior art, and the cost and time required for maintenance of the plating apparatus can be reduced. In addition, it can contribute to the compactness of the plating apparatus.
[0072]
In addition, since the conventional plating processing equipment uses resin-based piping, the amount of precipitate on the inner wall increases due to an increase in the surface roughness of the inner surface of the piping. In non-contact flowmeters using ultrasonic waves, etc. Although stable numerical values could not be obtained, in this embodiment, by changing to a glass-based material pipe, precipitation in the pipe can be suppressed, and even non-contact flowmeters (ultrasonic waves) can be measured stably. Became possible. In addition, by using a non-contact flow meter (ultrasonic wave), it has been possible to eliminate resistance in the pipe such as a float so far and obtain a more stable flow rate.
[0073]
Resin materials such as polypropylene have a thermal conductivity of 4.2 to 4.5 × 10 ^-Four (Cal / cm · sec · ° C), whereas the thermal conductivity of glass-based materials such as hard glass is 26.0 to 30.0 × 10 ^-Four (Cal / cm · sec · ° C), an order of magnitude larger than resin.
[0074]
Therefore, if the heat exchange unit for controlling the temperature of the plating solution is made of glass, it can be made much smaller than the case of resin. Further, in combination with the miniaturization of the heat exchange unit, it is possible to suppress the deposition of metal, and the temperature of the plating solution that can only be achieved in the buffer tank in the conventional plating apparatus can be controlled in the storage tank. As a result, accurate temperature control of the plating solution at a place closer to the plating tank is possible.
[0075]
As the heat exchange unit, a honeycomb-shaped unit in which thin tubes that are normally used are bundled may be immersed in the plating solution of the storage tank 1, but in this embodiment, the storage tank 1 is made of glass. Utilizing the fact that the thermal conductivity is good, for example, as illustrated in FIG. 1, even if the storage tank 1 is directly inserted into a separately provided heating tank 10, the desired temperature control is possible. In this case, since a special heat exchange unit is not immersed in the plating solution, metal deposition can be further suppressed. For example, warm water is put in the heating tank 10, and the plating solution in the storage tank 1 is warmed by heat conduction with this warm water.
[0076]
In the above, an example in which resin piping is used as the piping from the plating treatment tank 2 to the buffer tank 3 and the piping from the buffer tank 3 to the filter 6 through the circulation pump 4 has been described. There is no particular problem in making the piping during this period from glass in terms of suppressing metal deposition. However, since the pipes near the pump may be damaged by glass due to vibrations of the pump, etc., special consideration is required when changing to glass-based materials.
[0077]
By changing the material of the piping and other tanks of other parts to glass-based materials, it becomes possible to make the portion corresponding to about 90% of the total wetted area of the plating solution into glass-based materials. It has become possible to suppress the deposition on the surface of the apparatus other than the predetermined position (the plating target portion of the plating target object).
[0078]
In FIG. 1, the example in which the outlet of the plating solution from the storage tank 1 is provided on the bottom surface is shown, but it may be provided on the side surface. Even in this case, the temperature can be controlled using the same heating tank 10.
[0079]
1 shows an example in which the plating solution inlet to the plating tank 2 is provided on the side surface of the plating tank 2, but in order to control the thickness of the plating, Needless to say, it may be provided on the bottom surface, or a plurality of inlets may be provided.
[0080]
With such a configuration, metal deposition inside the plating processing apparatus can be prevented. As a result, it can be reduced that the metal peeled from the apparatus adheres to the semiconductor substrate and becomes defective. Therefore, the number of filters used for removing foreign substances can be reduced, and the cost and time for maintenance can be reduced.
[0081]
In addition, the temperature of the plating solution can be controlled at a location closer to the plating tank, and accurate temperature control can be achieved on the substrate to be plated.
[0082]
Here, a halogen-based chemical solution is used as a cleaning solution (removal agent), but this is an example in the case of gold (Au) plating. In addition, in the case of Cu plating, concentrated nitric acid or concentrated sulfuric acid can be used. In the case of Ni plating, concentrated hydrochloric acid or dilute nitric acid can also be used.
[0083]
As described above, the present invention has been described in detail by taking a semiconductor integrated circuit plating apparatus as an example. However, the present invention is not limited to a semiconductor apparatus other than a semiconductor integrated circuit, for example, a plating apparatus used in a manufacturing process of a compound semiconductor, Needless to say, can also be applied to a plating apparatus in a manufacturing process of a liquid crystal panel.
[0084]
The present invention includes a plating solution storage tank, a plating treatment tank into which the plating solution flows from the storage tank, a buffer tank into which the plating solution flows from the plating treatment tank, a flow meter for measuring the flow rate of the plating solution, In a semiconductor integrated circuit manufacturing apparatus comprising a heat exchange unit that controls the temperature of a plating solution, a filter that removes foreign matter in the plating solution, a pump that circulates the plating solution, and a pipe that connects each tank. The portion in contact with the substrate may be made of a material having a surface roughness change rate of 10% or less compared to the initial value due to cleaning with a halogen-based chemical solution.
[0085]
Further, in the above configuration, the material whose surface roughness change rate accompanying cleaning with the halogen-based chemical solution is 10% or less compared to the initial value may be configured to be hard glass or quartz glass. .
[0086]
In the above configuration, the plating solution flow meter may be configured to measure the plating solution in a non-contact manner using ultrasonic waves.
[0087]
Moreover, in the said structure, you may comprise so that a part of piping which connects each said tank may be comprised with hard glass or quartz glass.
[0088]
In the above configuration, the temperature of the plating solution may be controlled in the storage tank.
[0089]
【The invention's effect】
As described above, the plating apparatus of the present invention has a surface roughness change rate that is higher than that of the resin when at least a part of the portion that comes into contact with the plating solution is measured under the same conditions when the removing agent is applied. It is the structure formed with the low material.
[0090]
As a result, when the plating agent is deposited at an undesired position after the plating process and the removing agent is applied, the surface is not easily roughened. The acceleration of the precipitation of the substance can be suppressed. Therefore, there is an effect that it is possible to easily and effectively suppress the precipitation of the plating substance as a foreign matter generated in the plating process.
[0091]
The plating apparatus of the present invention further includes a plating treatment tank for bringing the object to be plated into contact with the plating solution in addition to the above-described configuration, and the wall surface of the plating treatment tank is the same when the removing agent is applied. It is the structure formed with the material whose surface roughness change rate is lower than resin when measured on condition.
[0092]
Thereby, in addition to the effect by said structure, there exists an effect that precipitation of the plating substance as a foreign material which generate | occur | produces by plating processing can be suppressed more easily and effectively.
[0093]
In addition to the above-described configuration, the plating apparatus of the present invention includes a plating tank for bringing a plating object into contact with a plating solution, and a pipe for a plating tank that carries the plating solution to the plating tank. The wall surface of the plating tank pipe is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied.
[0094]
Thereby, in addition to the effect by said structure, there exists an effect that precipitation of the plating substance as a foreign material which generate | occur | produces by plating processing can be suppressed more easily and effectively.
[0095]
In addition to the above configuration, the plating apparatus of the present invention includes a plating tank for bringing a plating object into contact with a plating solution, and a storage tank for storing a plating solution to be put into the plating tank, and the storage The wall surface of the tank is formed of a material whose surface roughness change rate is lower than that of the resin when measured under the same conditions when the removing agent is applied.
[0096]
Thereby, in addition to the effect by said structure, there exists an effect that precipitation of the plating substance as a foreign material which generate | occur | produces by plating processing can be suppressed more easily and effectively.
[0097]
In addition to the above configuration, the plating apparatus of the present invention includes a heating tank in which the storage tank is placed and the plating solution in the storage tank is heated by heat conduction.
[0098]
Thereby, in addition to the effect by said structure, there exists an effect that precipitation of the plating substance as a foreign material which generate | occur | produces by plating processing can be suppressed more easily and effectively.
[0099]
In addition to the above-described configuration, the plating apparatus of the present invention includes a plating tank for bringing a plating object into contact with a plating solution, and a pipe for a plating tank that carries the plating solution to the plating tank. An ultrasonic flow meter is disposed in a part of the plating tank pipe, and the wall surface of the plating treatment pipe in which the ultrasonic flow meter is disposed removes the removing agent. When it is made to act, it is the structure formed with the material whose surface roughness change rate is lower than resin when it measures on the same conditions.
[0100]
Thereby, in addition to the effect by said structure, there exists an effect that precipitation of the plating substance as a foreign material which generate | occur | produces by plating processing can be suppressed more easily and effectively.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a configuration example of a plating apparatus according to the present invention.
FIG. 2 is an explanatory view showing the rate of change in surface roughness due to a halogen-based chemical solution (iodine) of each material.
FIG. 3 is an explanatory view showing a configuration example of a conventional plating apparatus.
[Explanation of symbols]
1 Storage tank
2 Plating tank
3 Buffer tank
4 Circulation pump
6 Filter
8 Piping
9 Piping
10 Heating tank
11 Flow meter

Claims (5)

A plating solution containing a plating material is supplied, and the plating object is plated by bringing the plating object into contact with the plating solution. When the plating material is deposited at an undesired position, the plating material is removed with a removing agent. In the plating processing apparatus to remove
A plating tank for bringing a plating object into contact with a plating solution;
A storage tank for storing a plating solution to be put into the plating tank;
A plating tank for carrying a plating solution from the storage tank to the plating tank;
The storage tank is arranged at a position higher than the plating treatment tank so that the flow rate of the plating solution supplied to the plating treatment layer by the dead weight of the plating solution is adjusted to a predetermined flow rate. Yes,
An ultrasonic type flow meter is arranged in a part of the piping for the plating treatment tank,
The plating apparatus characterized in that the wall surface of the plating tank pipe is formed of hard glass or quartz glass. Wall surfaces of the plating tank and the storage tank are
2. The plating apparatus according to claim 1, wherein the plating apparatus is made of hard glass or quartz glass. Plating apparatus for putting the storage tank, according to claim 1, characterized in that it comprises a heating tank for heating the plating solution storage tank by thermal conduction during. A bumper for a semiconductor integrated circuit is formed by plating using the plating apparatus according to any one of claims 1 to 3. 4. A method of manufacturing a semiconductor integrated circuit, wherein the bump electrode of the semiconductor integrated circuit is formed by plating using the plating apparatus according to any one of claims 1 to 3.

Images