JPH11274201A - Manufacture of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent side etching of a substrate metal layer. SOLUTION: After an oxide film 2, an aluminum electrode pad 3 and a surface protecting film 4 are formed on a semiconductor substrate 1, a through hole is formed on the aluminum electrode pad 3. After a substrate metal layer 5 is formed on the entire surface, a photosensitive resin film 6 is deposited on the entire surface. Exposure and development are performed, and a bump- electrode forming pattern is formed. An expanding part is formed at the interface with the substrate metal layer 5 at the photosensitive resin film. Thereafter, the surface of the exposed substrate metal layer 5 is etched. With the substrate metal layer 5 as the electrode, a plated layer is formed in the through hole. The pattern is removed by etching solvent for the photosensitive resin film. With a bump electrode 7s as a mask, the substrate metal layer is removed by etching.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device having a bump electrode.

[0002]

2. Description of the Related Art Conventionally, as a method of manufacturing a bump formed on a semiconductor substrate, the following method is generally performed. First, an electrode pad is formed on a semiconductor substrate, and a surface protective film is formed on the entire surface of the substrate. Next, a through hole is formed in a portion of the surface protection film corresponding to the electrode pad. Thereafter, a plurality of base metal layers are sequentially formed on the entire surface of the semiconductor substrate by a sputtering method or the like. As the underlayer metal layer, Cr-Cu, Cr-Cu-Au, Ti-Au, Ti-
Pt, Ti-Pd, Ti / W-Au, Ti / W-Pd and the like are used.

After a photosensitive resin film is coated on the entire surface of a base metal, a pattern for forming a bump is formed in a part of the electrode pad. Next, a predetermined current is supplied using the base metal layer as one common electrode, and gold, copper, solder, or the like is electrodeposited by electroplating to form a bump electrode.

After removing the photosensitive resin film with a removing solvent or the like,
By using the bump electrode as a mask and removing the underlying metal layer other than the one covered with the bump electrode by wet etching, the final electrode structure is obtained.

[0005]

However, the conventional method of manufacturing a semiconductor device has the following problems. After the formation of the bump electrode, it is necessary to use the bump electrode as an etching mask to etch away the underlying metal layer other than that covered by the bump electrode. At the time of this etching, a phenomenon occurs in which the underlying metal layer is etched to the inside of the dimension of the bump electrode (hereinafter referred to as side etching). Therefore, there is a problem that the contact area between the bump electrode and the underlying metal layer is reduced, and the shear strength of the bump electrode is reduced.

[0006]

According to the present invention, there is provided a method for manufacturing a semiconductor device, comprising: forming an electrode pad on a first insulating layer of a semiconductor substrate having the first insulating layer; Forming a conductive layer on the insulating layer including the electrode pad; and forming a second insulating layer having an opening at a position corresponding to the pad and having a widening portion at an interface with the conductive layer. Forming a layer on the conductive layer, etching the surface of the conductive layer exposed in the opening, and forming a plating layer in the opening using the conductive layer as an electrode. Removing the second insulating layer, and removing the conductive layer using the plating layer as a mask. Since the present invention is configured as described above, the position where etching of the base metal is started is located outside the base metal immediately below the plating electrode, and the base metal immediately below the plating electrode is not etched.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment FIGS. 1 to 4 are sectional views showing a method for manufacturing a semiconductor device according to a first embodiment of the present invention.

First, as shown in FIG. 1A, a circuit element (not shown) and an oxide film 2 are formed on a semiconductor substrate 1. Thereafter, aluminum is formed on the entire surface by a sputtering method or the like, and the aluminum is patterned by photolithography / etching.
An aluminum electrode pad 3 having a size of about m × 70 μm is formed.

After a surface protection film 4 is formed on the entire surface of the insulating film such as SiO2 to a thickness of, for example, about 0.8 to 1.4 μm by the CVD method, the surface protection on the aluminum electrode pad 3 is performed by photolithographic etching. The film 4 is removed, and a through hole is formed on the aluminum electrode pad 3.

Next, as shown in FIG. 1B, a plurality of base metals are sequentially formed on the entire surface of the semiconductor substrate 1 by sputtering or the like. As a configuration of the underlayer metal layer,
For example, it is formed of Ti5-a having good adhesion to aluminum and Pd5-b for preventing the diffusion of Au.

Next, as shown in FIG. 2A, a positive photosensitive resin film 6 is formed on the underlying metal layers Ti5-a and Pd5-b.
Is applied to the entire surface to a thickness of about 25 to 30 μm, and then, using a mask, a portion of the photosensitive resin film 6 on the aluminum electrode pad 3 is exposed and immersed in a photosensitive resin film etching solvent.
The exposed portion is etched, and above the aluminum pad 18 about 20 μm inside the aluminum electrode pad 3,
A bump electrode forming pattern made of a photosensitive resin film 6 having an opening of about 30 × 50 μm is formed.

Next, as a processing step for increasing the adhesion area between the bump electrode and the underlying metal layer, a solvent or the like having a dissolving effect on the photosensitive resin film 6 is dropped on the opening portion of the bump electrode forming pattern. Then, the opening of the photosensitive resin film is increased by 2 to 5 μm in the lateral direction. FIG. 2B shows an enlarged view of FIG. 2A.

Next, as a processing step for removing impurities such as an oxide film on the surface of the base metal layer, Pd5-
b. An etchant having a dissolving effect on b (nitric acid, hydrochloric acid,
Sulfuric acid and a mixture thereof) are dropped onto the opening of the bump electrode forming pattern, and as shown in FIG. 3A, the Pd5-b of the underlying metal layer is etched by 100 to 500 [deg.]. Thereafter, a current is supplied using the underlying metal layers 5-a and 5-b as one common electrode, thereby performing Au plating to make the structure shown in FIG.
A bump electrode 7 is formed as shown in FIG.

Next, as shown in FIG. 4, the photosensitive resin film 6 is removed with a removing solvent or the like, and the underlying metal layers 5-a and 5-b are further removed by etching using the bump electrodes 7 as a mask. A bump electrode structure is obtained.

As described above, according to the first embodiment, the step of increasing the opening size of the photosensitive resin film and the step of slightly etching the surface of the underlying metal layer are provided immediately before the electroplating for forming the bump electrode. For this reason, the adhesion area between the bump electrode and the underlying metal layer can be increased, and the adhesion between the bump electrode and the underlying metal layer can be improved by removing impurities and the like on the surface of the underlying metal layer. To reduce, even if it occurs, after the adhesion area between the bump electrode and the underlying metal layer becomes larger than before, and after increasing the aperture size of the photosensitive resin film,
By removing the impurities and the like on the surface of the base metal layer, the area of the base metal layer from which the impurities and the like have been removed is increased, so that the shear strength of the bump electrode can be improved, and the quality of the bump electrode formation process can be expected to be improved.

Further, an etchant (such as nitric acid, hydrochloric acid, sulfuric acid, or a mixture thereof) is dropped on the opening of the bump electrode forming pattern, and Pd5-b of the underlying metal layer is coated with 100 to 5 μm.
After the etching, the base metal layer is used as an anode and the anode used for gold plating is used as a cathode, and the reverse electrolysis is applied to the base metal layer, so that the surface of the base metal layer is electrolytically removed by about 100 °. Gold plating may be formed. This makes it possible to remove even a small amount of impurities generated after etching the surface of the base metal layer, so that the adhesion between the gold plating and the base metal can be further improved.

Further, an etchant (such as nitric acid, hydrochloric acid, sulfuric acid, or a mixture thereof) is dropped on the opening of the bump electrode forming pattern, and Pd5-b of the underlying metal layer is coated with 100 to 5%.
After etching by 00 °, the base metal layer may be electrolytically removed by about 100 ° by exposing it to a cyan plating solution for about 60 seconds to 300 seconds (or more), and then gold plating may be formed. In this case, since the etching is performed while the surface of the underlying metal layer is planarized, a reduction in the occurrence rate of abnormal bump electrode shapes can be expected.

In the first embodiment, the photosensitive resin film shown in FIG. 2A is formed, and a solvent or the like having a dissolving effect on the photosensitive resin film 6 is opened to form the bump electrode forming pattern. It is dropped on the hole part, and the opening part of the photosensitive resin film is
The process for increasing the contact area between the bump electrode and the underlying metal layer after removing the layer by 5 μm and removing impurities such as an oxide film on the surface of the underlying metal layer includes the following steps.

For example, immediately before the gold plating treatment, the surface of the base metal layer is formed to have a surface area of 100 to 500 ° C. by applying an electrolysis reverse to the usual electrolysis to the base metal layer using the base metal layer as an anode and the anode used during gold plating as a cathode. Electrolytic removal. Immediately thereafter, a bump electrode is formed by Au plating by supplying current in the same plating tank with the underlying metal layer 5 as one common electrode. In this way, the quality of the bump electrode forming step can be expected to be improved without providing any special equipment (for pre-plating treatment).

As another method, the surface of the semiconductor substrate is exposed to the plating solution for about 60 to 300 seconds (or more) for dissolving the underlying metal layer with the cyan plating solution immediately before the gold plating process. Good. This dissolves and removes the underlying metal layer by about 100 to 500 °. Immediately thereafter, a current is supplied using the underlying metal layer as one common electrode, thereby forming a bump electrode by Au plating. In this way, the quality of the bump electrode formation process can be expected to be improved without providing special (for pre-plating) equipment, and a slight amount of etching is performed while flattening the surface of the underlying metal layer. Therefore, it is possible to reduce the occurrence rate, and expect improvement in the quality of the bump electrode forming step.

Second Embodiment FIGS. 5 to 6 are cross-sectional views showing a method of manufacturing a semiconductor device according to a second embodiment of the present invention. The same components as those in the first embodiment have the same reference numerals. And description thereof is omitted.

In the second embodiment, a circuit element (not shown) and an oxide film 2 are formed on a semiconductor substrate 1. afterwards,
Aluminum is formed on the entire surface by sputtering or the like, and the aluminum is patterned by photolithography / etching to form an aluminum electrode pad 3 having a size of, for example, about 50 μm × 70 μm at a position where a bump electrode is to be formed. afterwards,
After a surface protective film 4 is formed on the entire surface of the insulating film such as SiO2 to a thickness of, for example, about 0.8 to 1.4 μm by the CVD method, the surface protective film 4 on the aluminum electrode pad 3 is formed by photolithographic etching. After removal, a through hole is formed on the aluminum electrode pad 3.

Next, a plurality of base metals are sequentially formed on the entire surface of the semiconductor substrate 1 by sputtering or the like. The underlying metal layer may be composed of, for example, Ti5-a, which has good adhesion to aluminum, and Pd5-b for preventing diffusion of Au.
Is formed.

Next, the underlying metal layers Ti5-a, Pd5-b
After a positive photosensitive resin film 6 is coated on the entire surface to a thickness of about 25 to 30 μm, a part of the photosensitive resin film 6 on the aluminum electrode pad 3 is exposed using a mask, and the photosensitive resin film 6 is exposed. The exposed portion is etched by immersion in an etching solvent for a conductive resin film. The photosensitive resin film 6 has an opening of about 30 × 50 μm above the aluminum pad 18 about 20 μm inside the aluminum electrode pad 3. A pattern for forming a bump electrode is formed. The steps up to here are formed by the same steps as in the first embodiment.

Next, as a processing step for increasing the adhesion area between the bump electrode and the underlying metal layer and for removing impurities such as an oxide film on the surface of the underlying metal layer, a dissolving action on Pd5-b of the underlying metal layer is performed. An etchant (such as nitric acid, hydrochloric acid, sulfuric acid, or a mixture thereof) is dropped on the opening of the bump electrode forming portion, and the underlying metal layer Pd5-b is etched by 100 to 500 °.

Further, as a treatment for removing impurities such as an oxide film on the surface of the base metal layer adhered during the processing such as cleaning and drying after the etching, the base metal layer 5 is formed immediately before the gold plating processing.
By applying an electrolysis reverse to normal electrolysis to the base metal layer 5 using the anode as the anode and the anode used during gold plating as the cathode,
As shown in FIG. 5A, the surface of the underlying metal layer Pd5-b is
電解 Electrolytic removal to the extent.

Immediately after that, in the plating tank from which the base metal layer Pd5-b has been electrolytically removed, a current is supplied using the base metal layer 5 as one common electrode, thereby performing Au plating.
A bump electrode 7 is formed as shown in FIG.

Next, as shown in FIG. 6, the photosensitive resin film 6 is removed with a removing solvent or the like, and the underlying metal layers 5-a and 5-b are removed by etching to obtain a final bump electrode structure. .

As described above, according to the second embodiment, the step of etching the surface of the base metal layer by a small amount and the step of removing the oxide film and the like on the surface of the base metal layer by reversing the electrolysis direction inside the plating apparatus are performed. By providing this, the adhesion area between the bump electrode and the underlying metal layer can be increased, and the adhesion between the bump electrode and the underlying metal layer can be improved by removing impurities and the like on the surface of the underlying metal layer.

Therefore, it is necessary to reduce the amount of side etching during the etching of the underlying metal layer, to increase the adhesion area between the bump electrode and the underlying metal layer even if it occurs, and to reduce the surface of the underlying metal layer by a small amount. By providing a process to remove even a small amount of impurities generated after the etching process, impurities contained in the interface with the underlying metal layer can be reduced and the adhesion can be improved, and the shear strength of the bump electrode can be improved. As a result, improvement in the quality of the bump electrode forming step can be expected.

Immediately before the gold plating treatment, the base metal layer 5 is used as an anode and the anode used during gold plating is used as a cathode. As a treatment for flattening the surface of the metal layer, the surface of the semiconductor substrate is treated with a cyan plating solution for 6 minutes.
The base metal layer Pd5-b may be electrolytically removed by about 100 ° by exposing for about 0 to 300 seconds (or more).

Further, an etching solution (such as nitric acid, hydrochloric acid, sulfuric acid, or a mixture thereof) is dropped on the opening of the bump electrode forming portion, and the step of etching Pd5-b of the base metal layer by 100 to 500 ° is omitted. Immediately before the gold plating treatment, the base metal layer 5 is used as an anode, the anode used during gold plating is used as a cathode, and the reverse metallization is applied to the base metal layer 5 to remove the base metal by 100 to 500 °. As a treatment for flattening the layer surface, the base metal layer Pd5-b may be electrolytically removed by about 100 ° by exposing the semiconductor substrate surface to a cyan plating solution for about 60 to 300 seconds (or longer).

Further, in the second embodiment, immediately before gold plating, the base metal layer 5 is used as an anode, and the anode used for gold plating is used as a cathode, so that the base metal layer 5 is subjected to electrolysis reverse to normal electrolysis. Instead of this, the surface of the semiconductor substrate is exposed to a cyan plating solution for about 60 to 300 seconds (or more) immediately before the gold plating treatment to electrolytically remove the base metal layer Pd5-b by about 100 °. You may. This makes it possible to electrolytically remove the surface of the base metal layer without switching the electrolysis method of the plating apparatus. In addition, a small amount of etching can be performed while flattening the surface of the underlying metal layer, and the occurrence rate of bump electrode shape abnormality can be reduced.

Third Embodiment FIGS. 7 and 8 are cross-sectional views showing a method of manufacturing a semiconductor device according to a third embodiment of the present invention. And description thereof is omitted.

In the third embodiment, the base metal layer Ti5
After the photosensitive resin film 6 is applied over the entire surface of the Pd5-b, a hole is formed in a part of the aluminum electrode pad 3 where the bump electrode is to be formed.

Thereafter, a current is supplied by using the underlying metal layer 5 as one common electrode, and as shown in FIG.
The bump electrode 7 is formed by u plating, and the photosensitive resin film 6 is removed with a removing solvent or the like. And HNO ₃ (nitric acid) and H ₂ S
With a mixed solution of O ₄ (sulfuric acid) and CH ₃ COOH (acetic acid), only Pd5-b of the underlying metal layer is selectively removed without etching the bump electrode itself. Further, only Ti5-a other than the bonding portion of the bump electrode 7 is selectively removed by etching with H ₂ O ₂ (hydrogen peroxide solution) or hydrofluoric acid, etc., as shown in FIG. A simple bump electrode structure can be obtained.

For this reason, both the underlying metal layer and the bump electrode itself are simultaneously etched using the bump electrode as a mask, so that the bump electrode itself used as a mask is etched with the lapse of the etching processing time. It is possible to solve the problem caused by the decrease in the area in close contact with the layer and the decrease in the area of the base metal layer after etching (because the dimensions of the mask itself decrease). In addition, it is possible to use the bump electrode as a mask that always secures a constant area when etching the base metal layer, and it is possible to ensure a contact area between the bump electrode and the base metal layer. Furthermore, the occurrence of side etching below the bump electrode can be suppressed by the effect of CH ₃ COOH, and the contact area between the bump electrode and the underlying metal layer can be kept constant.

As for the solution for selectively etching Pd, HNO ₃ and H ₂ SO _{4 in the} etching solution are used.
FIG. 8 shows the respective concentrations of CH ₃ and CH ₃ COOH, and the Pd etching rate. In this case, the working conditions such as the concentration of the etching solution and the amount of the etching solution depend on Pd in the bump electrode forming step.
The etching is performed under the same conditions as the etching, and the amount of Pd etched for each concentration is measured. In FIG. 8, as an example, HNO ₃ -9%, H ₂ SO ₄ −
The correlation between the concentration ratio of the mixed solution of 85% (water-6%) and CH ₃ COOH and the Pd etching rate is shown in the graph. Here, each ratio indicates a weight ratio (wt%).

From FIG. 8, in order to shorten the etching time, HNO ₃ -9% and H ₂ SO ₄ -85% (water-
6%) to the mixture of 35% to 50% CH ₃ COOH.
% By weight. When the mixing ratio is set to around 40%, the etching rate is remarkably improved, and the workability of Pd etching is greatly improved. It can be seen that the etching rate for Pd is the fastest in the case of the composition of (water-6%).

Further, even when the concentration of the etching solution changes, HNO ₃ , H ₂ SO ₄ , CH ₃ COO in the solution may be changed.
By analyzing the concentration of H, the optimum etching time of Pd etching can be easily set, and a reduction in member costs due to the long-term use of the etching solution can be expected.

Further, the invention described in the third embodiment is as follows.
The present invention can be appropriately used in the inventions described in the first embodiment and the second embodiment. That is, according to the inventions described in the first and second embodiments, the steps up to the formation of the bumps are performed, and the etching solution in the third embodiment can be used when etching the underlying metal layer using the bumps as a mask.

[0042]

According to the semiconductor devices according to the first and second embodiments of the present invention, the bonding area between the bump electrode and the underlying metal layer can be increased, or the adhesion between them can be improved. Therefore, side etching can be prevented when the base metal layer is etched using the bump electrode as a mask, and since the surface of the base metal layer is flattened, the occurrence rate of bump electrode shape abnormality can be reduced. Furthermore, according to the third embodiment, when the base metal layer is removed by etching, the etching solution containing CH3COOH in a weight ratio of 35% to 50% is removed, so that the base metal is etched without etching the bump electrode itself. The layer can be removed by etching while suppressing the occurrence of side etching.

[Brief description of the drawings]

FIG. 1 is a process chart showing a first embodiment of the present invention.

FIG. 2 is a process chart showing a first embodiment of the present invention.

FIG. 3 is a process chart showing a first embodiment of the present invention.

FIG. 4 is a process chart showing a first embodiment of the present invention.

FIG. 5 is a process chart showing a second embodiment of the present invention.

FIG. 6 is a process chart showing a second embodiment of the present invention.

FIG. 7 is a process chart showing a third embodiment of the present invention.

FIG. 8 is a process chart showing a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 2 Oxide film 3 Aluminum electrode pad 4 Surface protective film 5-a Base metal layer 5-b Base metal layer 6 Photosensitive resin film 7 Bump electrode

Claims (16)

[Claims] A step of forming an electrode pad on the first insulating layer of the semiconductor substrate having the first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; While having an opening at the position corresponding to the pad,
Forming a second insulating layer having a spread portion at the interface with the conductive layer on the conductive layer, etching the surface of the conductive layer exposed to the opening, A semiconductor comprising: a step of forming a plated layer in the opening as an electrode; a step of removing the second insulating layer; and a step of removing the conductive layer using the plated layer as a mask. Device manufacturing method. A step of forming an electrode pad on the first insulating layer of the semiconductor substrate having the first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; While having an opening at the position corresponding to the pad,
Forming a second insulating layer having a spread portion at an interface with the conductive layer on the conductive layer; and electrolyzing a surface of the conductive layer exposed to the opening using the conductive layer as a first electrode. Removing the conductive layer and the second electrode, which is an electrode opposite to the first electrode.
Forming a plating layer in the opening as an electrode, removing the second insulating layer, and removing the conductive layer using the plating electrode as a mask. A method for manufacturing a semiconductor device. A step of forming an electrode pad on the first insulating layer of the semiconductor substrate having the first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; While having an opening at the position corresponding to the pad,
Forming a second insulating layer having a spread portion at the interface with the conductive layer on the conductive layer; and thereafter, immersing the semiconductor substrate in a plating solution of a cyanide bath for a predetermined period of time. A semiconductor comprising: a step of forming a plating layer in the opening as an electrode; a step of removing the second insulating layer; and a step of removing the conductive layer using the plating electrode as a mask. Device manufacturing method. 4. a step of forming an electrode pad on the first insulating layer of the semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; A step of forming a second insulating layer having an opening on the conductive layer; a step of etching the surface of the conductive layer exposed to the opening; and the step of using the conductive layer as a first electrode. Electrolytically removing the surface of the conductive layer exposed to the opening, and forming the conductive layer on the second electrode opposite to the first electrode.
Forming a plating layer in the opening as the electrode, removing the second insulating layer, and removing the conductive layer using the plating layer as a mask. A method for manufacturing a semiconductor device. 5. A step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; A step of forming a second insulating layer having an opening on the conductive layer; a step of etching the surface of the conductive layer exposed to the opening; Forming a plating layer in the opening using the conductive layer as one electrode, removing the second insulating layer, and using the plating electrode as a mask to form the conductive layer. A method of manufacturing a semiconductor device, comprising: 6. a step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; Forming a second insulating layer having an opening on the conductive layer, and thereafter immersing the semiconductor substrate in a plating solution of a cyanide bath for a predetermined time, and then opening the opening using the conductive layer as a first electrode. Electrolytically removing the surface of the conductive layer exposed to the portion; and a second step of forming the conductive layer on an electrode opposite to the first electrode.
Forming a plating layer in the opening as an electrode, removing the second insulating layer, and removing the conductive layer using the plating electrode as a mask. A method for manufacturing a semiconductor device. 7. A step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; Forming a second insulating layer having an opening on the conductive layer; and thereafter, immersing the semiconductor substrate in a plating solution of a cyanide bath for a predetermined time, and then using the conductive layer as one electrode in the opening. Forming a plating layer on the substrate, removing the second insulating layer, and removing the conductive layer using the plating electrode as a mask. 8. The step of forming the plating layer includes: electrolytically removing a surface of the conductive layer exposed to the opening using the conductive layer as a first electrode; and forming the conductive layer with the first electrode. Is the opposite electrode, the second
Forming a plating layer in said opening as said electrode. 2. The method of manufacturing a semiconductor device according to claim 1, wherein 9. After the surface of the conductive layer exposed at the opening is etched or electrolytically removed, and before forming the plating layer, the conductive layer is immersed in a plating solution of a cyan bath for a predetermined time. 4. The method for manufacturing a semiconductor device according to claim 2, wherein 10. A step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; A step of forming a second insulating layer having an opening on the conductive layer; a step of forming a plating layer on the conductive layer exposed to the opening; and a step of removing the second insulating layer And a step of removing the conductive layer using a mixture of nitric acid, sulfuric acid, and acetic acid with the plating layer as a mask. 11. The method according to claim 9, wherein acetic acid is mixed with the mixed solution at a weight ratio of 35% to 50%. 12. A step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; While having an opening at the position corresponding to the pad,
Forming a second insulating layer having a spread portion at the interface with the conductive layer on the conductive layer; forming a plating layer in the opening using the conductive layer as an electrode; A method for manufacturing a semiconductor device, comprising: a step of removing a layer; and a step of removing the conductive layer using a mixed solution containing nitric acid, sulfuric acid, and acetic acid, using the plating layer as a mask. 13. A step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; A step of forming a second insulating layer having an opening on the conductive layer; a step of etching the surface of the conductive layer exposed to the opening; and an opening in the opening using the conductive layer as an electrode. Forming a plating layer, removing the second insulating layer, and removing the conductive layer using the plating layer as a mask by using a mixed solution containing nitric acid, sulfuric acid, and acetic acid. A method for manufacturing a semiconductor device, comprising: 14. A step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; Forming a second insulating layer having an opening on the conductive layer; electrolytically removing a surface of the conductive layer exposed to the opening using the conductive layer as a first electrode; The layer is a second electrode opposite to the first electrode;
A step of forming a plating layer in the opening as an electrode; a step of removing the second insulating layer; and Removing the semiconductor device. 15. A step of forming an electrode pad on the first insulating layer of a semiconductor substrate having a first insulating layer; a step of forming a conductive layer on the insulating layer including the electrode pad; Forming a second insulating layer having an opening on the conductive layer; and thereafter, immersing the semiconductor substrate in a plating solution of a cyanide bath for a predetermined time, and then using the conductive layer as one electrode in the opening. Forming a plating layer on the substrate, removing the second insulating layer, and removing the conductive layer using the plating layer as a mask by using a mixed solution containing nitric acid, sulfuric acid, and acetic acid. A method for manufacturing a semiconductor device, comprising: 16. The method according to claim 1, wherein the conductive layer is removed using a mixed solution containing nitric acid, sulfuric acid, and acetic acid when the conductive layer is removed using the plating layer as a mask.
10. The method for manufacturing a semiconductor device according to any one of items 9 to 9.