JP3274381B2 - Method for forming bump electrode of semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a projection electrode of a semiconductor device for forming a projection electrode necessary for mounting a semiconductor device by using a flip chip method or a TAB method.

[0002]

2. Description of the Related Art Conventionally, a semiconductor device usually has an external electrode for making an electrical connection to the outside. Usually, when packaging in a resin package or the like, a metal wire is connected to the external electrode. I do. For the external electrodes, Al used for wiring of the semiconductor element is used. In recent years, in response to demands for miniaturization and high performance of electronic equipment, the conventional resin package has been replaced with a TCP (Tape Carrier).
PKG) and a high-density mounting technology such as a flip chip method in which a bare chip is directly mounted on a circuit board. An external electrode of a semiconductor device used for these mounting techniques requires a projecting electrode for bonding.

[0003] A method of forming the protruding electrode will be described with reference to FIG. FIG. 4 is a process sectional view showing a conventional method for forming a bump electrode of a semiconductor device. In FIG. 4, 1
Denotes an Al electrode serving as an external electrode, 3 denotes a semiconductor device, 4 denotes a protective film, 5 denotes a Ni particle film, 6 denotes a Ni film, and 7 denotes an Au film.
As shown in FIG. 4A, before the protruding electrode is formed, the natural oxide film 2 is formed on the surface of the Al electrode 1; therefore, first, wet etching is performed by dipping in an aqueous solution of phosphoric acid or sodium hydroxide. By the process, the natural oxide film 2 formed on the surface of the Al electrode 1 is removed (FIG. 4B).

Next, a Ni particle film 5 is formed. This is because the natural oxide film 2 removed in the previous step is prevented from being re-formed on the Al electrode 1 and is kept at 80 ° C.
6 in an alkaline (pH 9 to 10) solution containing i.
By immersing for 0 second, a thickness of 300 to 5 is applied to the surface of the Al electrode 1 by utilizing a substitution reaction between Al and Ni ions in the solution.
A Ni particle film 5 having a thickness of 00 ° is formed (FIG. 4C).

Next, an electroless Ni plating step of immersing the semiconductor device 3 in an electroless Ni plating solution is performed. Here, the Ni particle film 5 formed in the previous step acts as a catalyst in the electroless Ni plating solution, and Ni is self-precipitated on the Ni particle film 5 by a self-reduction reaction of the electroless Ni plating solution.
An i film 6 is formed (FIG. 4D). Next, electroless A
An electroless Au plating step of immersing the semiconductor device 3 in a u plating solution is performed. This is because the Ni film 6 alone has poor connectivity due to the Ni oxide film, so that the A
The u film 7 is formed by a substitution reaction between Ni and Au ions in the electroless Au plating solution (FIG. 4E).

When the semiconductor device 3 is mounted on a bare chip, a projection electrode composed of a Ni particle film 5, a Ni film 6, and an Au film 7 formed on an Al electrode 1 serving as an external electrode is used.
It is directly connected to a circuit board by flip chip mounting, or packaged in TCP.

[0007]

In the projection electrode forming method shown in FIG. 4, the Ni film 6 is formed on the Al electrode 1 by electroless Ni.
Before forming by plating, as a pretreatment for electroless Ni plating, a Ni particle film 5 is formed by a substitution reaction between Al and Ni ions. This is because, prior to that, a method of laminating a Ni film and another metal film such as Au on an external electrode of a semiconductor device by an electroless plating method to form a protruding electrode is performed by using Zn as a pretreatment for electroless Ni plating. However, if there is a layer of Zn particles due to the Zn substitution treatment, the corrosion resistance of the Zn layer is extremely poor. Therefore, another metal film such as Au is plated on the Ni plating film by electroless plating. There is a drawback that the Zn layer is corroded by the infiltration of the plating solution during the lamination and the intrusion of moisture from the outside after the formation of the bump electrodes, and the adhesion between the Ni plating film and other metal films is deteriorated. ,
As an alternative to the Zn replacement process, a Ni replacement process has come to be used.

However, in the method of forming the protruding electrodes shown in FIG. 4, since the size of the particles of the Ni particle film 5 tends to vary, a gap is generated at the interface between the Ni particle film 5 and the Al electrode 1, and the contact resistance is reduced. There was a problem that the value was high. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for forming a protruding electrode of a semiconductor device, which can form a protruding electrode having a high adhesion to an external electrode of the semiconductor device and a low contact resistance value.

[0009]

According to a first aspect of the present invention, there is provided a method for forming a protruding electrode of a semiconductor device, comprising the steps of:
A method for forming a bump electrode of a semiconductor device in which a Ni particle film is formed as a pretreatment of electroless Ni plating, and a bump electrode is formed by stacking a Ni film and one or more other metal films by an electroless plating method. The step of forming the Ni particle film is characterized in that the step of forming discrete Ni particles on the external electrode and the cleaning step are repeated twice or more.

According to this method, the step of forming discrete Ni particles on the external electrode and the washing step are repeated two or more times, so that the Ni particle film is formed with Ni particles of uniform size without gaps. Therefore, no gap is formed between the external electrode and the Ni particle film. Then, a Ni film is formed on the Ni particle film, and another metal film is further formed thereon by an electroless plating method. When the other metal film is formed, a plating solution is applied to the interface between the external electrode and the Ni particle film. Without intrusion,
It is very easy to form a protruding electrode having high adhesion and a low contact resistance value on the external electrode surface.

According to a second aspect of the present invention, there is provided a method for forming a protruding electrode of a semiconductor device, comprising: forming a Ni particle film on an external electrode of the semiconductor device as a pretreatment for electroless Ni plating; A method of forming a bump electrode of a semiconductor device in which a bump electrode is formed by laminating at least one type of another metal film, wherein the step of forming a Ni particle film includes a first N
performing the step of forming the i-particles, the first cleaning step, the step of dissolving the first Ni particles, and the second cleaning step at least once, and then performing the step of forming the second Ni particles. Features.

According to this method, after the step of forming the first Ni particles, the first cleaning step, the step of dissolving the first Ni particles, and the second cleaning step are performed at least once, 2
The Ni particle film formed by performing the step of forming the Ni particles is formed of fine and uniform Ni particles without any gap, and a gap is formed between the external electrode and the Ni particle film. Never. Then, a Ni film is formed on the Ni particle film, and another metal film is further formed thereon by an electroless plating method. When the other metal film is formed, a plating solution is applied to the interface between the external electrode and the Ni particle film. It is possible to form a protruding electrode having high adhesion to the external electrode surface and low contact resistance very easily without intrusion.

According to a third aspect of the present invention, there is provided a method for forming a protruding electrode of a semiconductor device, comprising: forming a Ni particle film on an external electrode of the semiconductor device as a pretreatment for electroless Ni plating; A method for forming a bump electrode in a semiconductor device in which a bump electrode is formed by laminating at least one type of another metal film, wherein a Ni film forming step is performed after performing electroless Ni plating at a low deposition rate. It is characterized by performing electroless Ni plating at a high deposition rate.

According to this method, after forming the Ni particle film, when forming the Ni film, the gap between the Ni particle films is formed by performing electroless Ni plating at a low deposition rate. Since it is filled, no gap is formed between the external electrode and the Ni particle film. Then, after performing the electroless Ni plating at a high deposition rate, another metal film is formed by the electroless plating method. However, when the other metal film is formed, the interface between the external electrode and the Ni particle film is plated. No liquid intrusion,
It is very easy to form a protruding electrode having high adhesion and a low contact resistance value on the external electrode surface.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. [First Embodiment] First, a first embodiment of the present invention will be described. FIG. 1 is a process sectional view showing a method for forming a bump electrode of a semiconductor device according to a first embodiment of the present invention. In FIG. 1, 1 is an Al electrode which is an external electrode of the semiconductor device 3, 4 is a protective film, 6 is a Ni film, 7 is an Au film,
8 and 9 are Ni particle films.

First, before the formation of the bump electrodes, the natural oxide film (see FIG. 4) formed on the surface of the Al electrode 1 by a wet etching step of dipping the semiconductor device 3 in an aqueous solution of phosphoric acid or sodium hydroxide. Perform removal (Fig. 1
(A)). Thereafter, cleaning is performed with pure water. Next, as shown in FIG. 1B, a Ni particle film 8 is formed on the Al electrode 1. This is because the natural oxide film is removed by the process of FIG. 1A, but if left as it is, a natural oxide film is formed again on the Al electrode 1.
In order to prevent the formation of a natural oxide film on the upper surface, the substrate was immersed for 20 seconds in an alkaline (pH 9 to 10) solution containing Ni kept at 80 ° C., so that Al and N in the solution were removed.
A 300-500-nm-thick Ni particle film 8 is formed on the surface of the Al electrode 1 by utilizing the i-ion substitution reaction. This N
When the i-particle film 8 is formed, there is no natural oxide film on the Al electrode 1, but there are portions on the surface of the Al electrode 1 where the Ni substitution reaction proceeds and portions where the Ni substitution reaction does not proceed, so that the Ni particles are separated. The Ni particle film 8 of FIG. After forming the Ni particle film 8, cleaning is performed with pure water.

Next, as shown in FIG. 1C, a Ni particle film 9 is formed on the Al electrode 1 again. This is shown in FIG.
The Ni particle film 8 was formed by the step (b),
Since a portion where no Ni particles are deposited on the electrode 1 remains, the Ni kept at 80 ° C. which is the same as the treatment of FIG.
20 in an alkaline (pH 9 to 10) solution containing
By immersion for 2 seconds, a Ni particle film 9 in which Ni particles are precipitated is also formed in a gap between the Ni particle films 8. After the formation of the Ni particle film 9, cleaning is performed with pure water.

Next, as shown in FIG. 1D, a Ni film 6 is formed on the Ni particle film 9 formed on the Al electrode 1 without any gap by electroless plating. At this time, FIG.
The Ni particle film 9 formed in the step (c) acts as a catalyst in the electroless Ni plating solution, and Ni is self-precipitated on the Ni particle film 9 by a self-reduction reaction of the electroless Ni plating solution. 6 are formed. Specifically, the semiconductor device 3 is immersed in an electroless Ni plating solution maintained at 90 ° C. for 2 to 5 minutes, so that the Ni film 6 having a thickness of 1.0 to 2.0 μm is formed on the Al electrode 1 of the semiconductor device 3. To form After forming the Ni film 6, cleaning is performed with pure water.

Next, as shown in FIG. 1E, an Au film 7 is formed on the Ni film 6 by an electroless plating method. Specifically, the electroless Au holding the semiconductor device 3 at 90 ° C.
By immersing in a plating solution for 40 minutes, an Au film 7 of 0.2 μm is formed on the Ni film 6. After forming the Au film 7, cleaning is performed with pure water. According to this embodiment, as shown in FIGS. 1B and 1C, the Ni particle film 9 and the cleaning step are repeated twice, so that the Ni particle film 9 has a uniform size. The particles are formed without gaps, and no gaps are formed between the Al electrode 1 and the Ni particle film 9. As a result, when the Au film 7 is formed,
Since the electroless Au plating solution does not enter the interface between the 1 electrode 1 and the Ni particle film 9, it is possible to extremely easily form a protruding electrode having high adhesion and a low contact resistance value on the surface of the Al electrode 1.

In this embodiment, the final Ni
The particle film 9 is formed by two steps of forming a Ni particle and cleaning.
It is formed by repeating the process three times, but may be formed by repeating the process of forming Ni particles and the washing process three times or more. [Second Embodiment] Next, a second embodiment of the present invention will be described. FIG. 2 is a process sectional view showing a method for forming a bump electrode of a semiconductor device according to a second embodiment of the present invention. 2, reference numeral 1 denotes an Al electrode which is an external electrode of the semiconductor device 3, 4 denotes a protective film, 6 denotes a Ni film, and 7 denotes Au.
The films 10, 11 are Ni particle films.

First, before the formation of the bump electrodes, the natural oxide film (see FIG. 4) formed on the surface of the Al electrode 1 by a wet etching step of dipping the semiconductor device 3 in an aqueous solution of phosphoric acid or sodium hydroxide. Perform removal (Fig. 2
(A)). Thereafter, cleaning is performed with pure water. Next, as shown in FIG. 2B, a Ni particle film 10 is formed on the Al electrode 1.
To form This is because the natural oxide film is removed by the process of FIG.
Since a natural oxide film is formed on the Al electrode 1, the formation of the natural oxide film on the Al electrode 1 is prevented at 80 ° C.
Alkaline containing Ni (pH 9-10)
Is immersed in the solution for 30 seconds to form a Ni-particle film 10 having a thickness of 300 to 500 ° on the surface of the Al electrode 1 by utilizing a substitution reaction between Al and Ni ions in the solution. In the step of FIG. 2 (b), Ni particles are deposited on the entire surface of the Al electrode 1 by immersion (30 seconds) longer than the immersion time (20 seconds) of the step of FIG. 1 (b). But,
The size of the Ni particles varies. This Ni particle film 1
After forming 0, washing is performed with pure water.

Next, as shown in FIG. 2C, the Ni particle film 10 formed on the Al electrode 1 is removed. this is,
The Ni particle film 10 formed by the process of FIG.
The formation processing time is long, and Ni particles are precipitated on the entire surface of the Al electrode 1. However, since the size of the Ni particles varies, the semiconductor device 3 is immersed in a solution in which Ni is dissolved. The Ni particle film 10 is dissolved. Specifically, the semiconductor device 3 is placed in a 40% nitric acid solution or a hydrochloric acid solution.
By immersing for 0 second, all of the Ni particle film 10 is dissolved. After dissolution, washing is performed with pure water.

Next, as shown in FIG. 2D, a Ni particle film 11 is formed on the Al electrode 1 of the semiconductor device 3 again. This is because the Ni particle film 10 is formed by the process shown in FIG.
On the Al electrode 1 from which the Ni-containing alkaline (pH 9 to 9) used at FIG.
By dipping the semiconductor device 3 in the solution of 10) for 20 to 30 seconds, a dense and particle-size film having a thickness of 300 to 500 ° is formed on the surface of the Al electrode 1 by utilizing a substitution reaction between Al and Ni ions in the solution. Forms a uniform Ni particle film 11. After forming the Ni particle film 11, cleaning is performed with pure water.

Next, as shown in FIG. 2E, a Ni film 6 is formed by an electroless plating method on the Ni particle film 11 formed on the Al electrode 1 without any gap. At this time, FIG.
The Ni particle film 11 formed in the step (d) acts as a catalyst in the electroless Ni plating solution, and Ni is self-precipitated on the Ni particle film 11 by a self-reduction reaction of the electroless Ni plating solution. 6 are formed. Specifically, the semiconductor device 3 is placed in an electroless Ni plating solution held at 90 ° C.
By immersing for 5 minutes, the Al electrode 1 of the semiconductor device 3
A Ni film 6 having a thickness of 1.0 to 2.0 μm is formed thereon. This N
After forming the i-film 6, cleaning is performed with pure water.

Next, as shown in FIG. 2F, an Au film 7 is formed on the Ni film 6 by an electroless plating method. Specifically, the electroless Au holding the semiconductor device 3 at 90 ° C.
By immersing in a plating solution for 40 minutes, an Au film 7 of 0.2 μm is formed on the Ni film 6. After forming the Au film 7, cleaning is performed with pure water. Note that the formation of the Ni particle film 10 in the step of FIG. 2B is after removing the natural oxide film, and is not in a state where a uniform Ni substitution reaction is started on the entire surface of the Al electrode 1, but for a reaction time. , N
The Ni particle film 10 has a variation in i-particle size. On the other hand, when the Ni particle film 11 is formed in the step of FIG. 2D, the surface of the Al electrode 1 is a surface that has undergone Ni substitution reaction once, so that the Ni surface is uniform over the entire surface of the Al electrode 1.
This is a state in which the substitution reaction is likely to occur, and the Ni particle film 11 having a uniform particle size can be formed.

According to this embodiment, the Ni particle film 10
After forming, washing, dissolving and removing the Ni particle film 10 and washing, the Ni particle film 11 is formed, so that Ni particles having a fine and uniform size are formed without gaps. Thus, no gap is formed between the Al electrode 1 and the Ni particle film 11. As a result, since the electroless Au plating solution does not enter the interface between the Al electrode and the Ni particle film 11 during the formation of the Au film 7, the adhesion to the surface of the Al electrode 1 is extremely easily increased, and the projection having a low contact resistance value is obtained. Electrodes can be formed.

In this embodiment, the Ni particle film 10 is formed before the Ni particle film 11 finally used.
Washing, dissolving and removing the Ni particle film 10 and washing are performed once, but may be performed two or more times. [Third Embodiment] Next, a third embodiment of the present invention will be described. FIG. 3 is a process sectional view showing a method for forming a bump electrode of a semiconductor device according to a third embodiment of the present invention. 3, reference numeral 1 denotes an Al electrode which is an external electrode of the semiconductor device 3, 4 denotes a protective film, 5 denotes a Ni particle film, and 6, 1
2 is a Ni film and 7 is an Au film.

First, before the formation of the bump electrode, the natural oxide film (see FIG. 4) formed on the surface of the Al electrode 1 by a wet etching step of dipping the semiconductor device 3 in an aqueous solution of phosphoric acid or sodium hydroxide. Perform removal (Fig. 3
(A)). Thereafter, cleaning is performed with pure water. Next, a Ni particle film 5 is formed on the Al electrode 1 as shown in FIG. This is because the natural oxide film is removed by the process of FIG. 3A, but if left as it is, the natural oxide film is formed again on the Al electrode 1.
In order to prevent the formation of a natural oxide film on the upper surface, the aluminum and the N in the solution were immersed in an alkaline (pH 9 to 10) solution containing Ni maintained at 80 ° C. for 60 seconds.
A 300-500-nm-thick Ni particle film 5 is formed on the surface of the Al electrode 1 by utilizing the i-ion substitution reaction. This N
After forming the i-particle film 5, cleaning is performed with pure water.

Next, as shown in FIG. 3C, a Ni film 12 is formed on the Al electrode 1 by an electroless plating method having a low deposition rate (0.5 μm / hr or less). This is because the Ni particle film 5 formed in the step of FIG.
Acts as a catalyst in the electroless Ni plating solution,
Ni on the Ni particle film 5 by the self-reduction reaction of the i-plating solution
Is self-deposited, and a Ni film 12 is formed. At this time, since the deposition rate of the electroless Ni plating is low, the Ni film 12 fills the gap between the Ni particle films 5. Specifically, the semiconductor device 3 is immersed in the electroless Ni plating solution maintained at 60 ° C. for 5 to 15 minutes to reduce the deposition rate to 0.05 to 0. 1 μm
Is formed. After forming the Ni film 12, cleaning is performed with pure water.

Next, as shown in FIG.
The Ni film 6 is formed on the Ni film 12 formed in the step (c) by an electroless plating method with a high deposition rate (10 μm / hr or more). At this time, the Ni film 12 formed in the step of FIG. 3C acts as a catalyst in the electroless Ni plating solution, and Ni self-precipitates on the Ni film 12 by a self-reduction reaction of the electroless Ni plating solution. , Ni film 6 is formed. Specifically, to increase the deposition rate to 90 ° C.
Semiconductor device 3 in the electroless Ni plating solution held in
By immersing for 5 minutes, 1.0 to 1.0
A 2.0 μm Ni film 6 is formed. After forming the Ni film 6, cleaning is performed with pure water.

Next, as shown in FIG. 3E, an Au film 7 is formed on the Ni film 6 by an electroless plating method. Specifically, the electroless Au holding the semiconductor device 3 at 90 ° C.
By immersing in a plating solution for 40 minutes, an Au film 7 of 0.2 μm is formed on the Ni film 6. After forming the Au film 7, cleaning is performed with pure water. According to this embodiment, after the Ni particle film 5 is formed, when the Ni film is formed, the Ni deposition is first performed by electroless Ni plating at a low deposition rate (0.5 μm / hr or less). Since the gap between the particle films 5 is filled with the Ni film 12, no gap is formed between the Al electrode 1 and the Ni particle film 5. as a result,
Since there is no intrusion of the electroless Au plating solution into the interface between the Al electrode 1 and the Ni film 5 during the formation of the Au film 7, Al
A protruding electrode having high adhesion and low contact resistance can be formed on the surface of the electrode 1.

In the first, second, and third embodiments, the Au film 7 is formed on the Ni film 6 in the electroless plating step, but instead of the Au film 7, a Cu film and a Pd film are used. Alternatively, a Pt film or the like may be formed in an electroless plating process.

[0033]

According to the method for forming a bump electrode of a semiconductor device according to the first aspect of the present invention, a Ni particle film formed by repeating a step of forming discrete Ni particles on an external electrode and a cleaning step at least twice is used. Thus, Ni particles of uniform size are formed without gaps, and no gaps are formed between the external electrode and the Ni particle film. Then, a Ni film is formed on the Ni particle film, and another metal film is further formed thereon by an electroless plating method.
There is no intrusion of the plating solution into the interface with the i-particle film, and it is possible to extremely easily form a protruding electrode having a high adhesion to the external electrode surface and a low contact resistance value.

According to a second aspect of the present invention, a method for forming a bump electrode of a semiconductor device includes a step of forming first Ni particles, a first cleaning step, a step of dissolving the first Ni particles, and a second cleaning step. The Ni particle film formed by performing the step of forming the second Ni particles after performing one or more times becomes a film in which fine and uniform Ni particles are formed without gaps, and the external electrode and Ni particles are formed. No gap is formed between the particle films. Then, a Ni film is formed on the Ni particle film, and another metal film is further formed thereon by electroless plating.
A plating solution does not enter the interface between the external electrode and the Ni particle film at the time of forming the other metal film, and a projection electrode having high adhesion and a low contact resistance value can be formed extremely easily on the external electrode surface.

According to a third aspect of the present invention, in the method of forming a bump electrode for a semiconductor device, a Ni particle film is formed as a pretreatment for electroless Ni plating, and then, when a Ni film is formed, the deposition rate is low at first. By performing the Ni plating, the gap between the Ni particle films is filled with the Ni film, so that no gap is formed between the external electrode and the Ni particle film. Then, after performing the electroless Ni plating at a high deposition rate, another metal film is formed by the electroless plating method. However, when the other metal film is formed, the interface between the external electrode and the Ni particle film is plated. It is possible to extremely easily form a protruding electrode having high adhesion to the external electrode surface and low contact resistance value without liquid intrusion.

[Brief description of the drawings]

FIG. 1 is a process sectional view illustrating a method for forming a bump electrode of a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a process sectional view illustrating a method for forming a bump electrode of a semiconductor device according to a second embodiment of the present invention.

FIG. 3 is a process sectional view illustrating a method for forming a bump electrode of a semiconductor device according to a third embodiment of the present invention.

FIG. 4 is a process sectional view showing a method for forming a bump electrode of a conventional semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Al electrode (external electrode) 2 Natural oxide film 3 Semiconductor device 4 Protective film 5 Ni particle film 6 Ni film 7 Au film 8 Ni particle film 9 Ni particle film 10 Ni particle film 11 Ni particle film 12 Ni film

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-17450 (JP, A) JP-A-6-232136 (JP, A) JP-A-9-69524 (JP, A) JP-A-9-69 232318 (JP, A) JP-A-9-326395 (JP, A) JP-A-10-256257 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 21/60 C23C 18 / 00

Claims (3)

(57) [Claims] An electroless Ni is provided on an external electrode of a semiconductor device.
A method for forming a protruding electrode of a semiconductor device, comprising: forming a Ni particle film as a pretreatment for plating; and laminating a Ni film and at least one other metal film by electroless plating to form a protruding electrode. The method of forming a bump electrode of a semiconductor device, wherein the step of forming the Ni particle film includes repeating a step of forming discrete Ni particles on the external electrode and a cleaning step at least twice. 2. The method according to claim 1, wherein electroless Ni
A method for forming a protruding electrode of a semiconductor device, comprising: forming a Ni particle film as a pretreatment for plating; and laminating a Ni film and at least one other metal film by electroless plating to form a protruding electrode. The step of forming the Ni particle film is performed after the step of forming the first Ni particles, the first cleaning step, the step of dissolving the first Ni particles, and the second cleaning step are performed at least once. Forming a second Ni particle by performing a step of forming a second Ni particle. 3. An electroless Ni on an external electrode of a semiconductor device.
A method for forming a protruding electrode of a semiconductor device, comprising: forming a Ni particle film as a pretreatment for plating; and laminating a Ni film and at least one other metal film by electroless plating to form a protruding electrode. In the step of forming the Ni film, the deposition rate is low.
A method for forming a protruding electrode of a semiconductor device, comprising: performing i-plating and then performing electroless Ni plating at a high deposition rate.