JP3060710B2 - Method and apparatus for manufacturing electrical contact material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to, for example, industrial equipment,
The present invention relates to a method and an apparatus for manufacturing a material for electrical contacts used for electrical contacts such as wiring connection terminals, relays, and switches mounted on automobiles and the like.

[0002]

2. Description of the Related Art An electrical contact that is electrically connected to a conductive member by contact with the conductive member has a base material made of copper and a copper-based alloy such as brass. In order to improve the corrosion resistance and the contact characteristics, a film of a metal such as gold, nickel and tin is formed on the surface. Of these, tin (Sn)
In general, a tin film is formed on the surface of a base material by a so-called wet process (wet process) such as an electrolytic plating method, an electroless plating method, and a hot dipping method.

[0003] In such an electric contact, there is a problem that the base material constituent element (Cu, Zn) which causes deterioration of the contact characteristics is diffused into the tin film. In particular, the operating environment temperature is high and 100
When the temperature exceeds ° C, the above-mentioned diffusion phenomenon appears remarkably. For example, copper of the base material diffuses to the tin film side, and an alloy is formed by copper and tin. This alloy of copper and tin has a high hardness, and deteriorates adhesion when contacting a conductive member to increase contact resistance.
Further, when the zinc element of the base material is diffused, it deposits on the surface of the tin film to form zinc oxide having low conductivity on the surface of the tin film, and the contact characteristics are deteriorated, for example, the contact resistance is increased as described above. As described above, the conventional electrical contact is inferior in heat resistance. For example, diffusion occurs at the periphery of the engine of an automobile having a high use environment temperature, and the contact characteristics are deteriorated.

On the other hand, a technique has been developed in which a zinc diffusion barrier layer made of pure copper is formed between a base material and a tin film, and the diffusion of the constituent elements of the base material is suppressed by the barrier layer. However, also in this case, an alloy having high hardness similar to the above is formed due to the interdiffusion between copper of the barrier layer and tin of the tin film, and the contact characteristics are not deteriorated. In particular, when the alloying of pure copper and tin progresses and the alloy layer reaches the interface with the base material, the alloy layer promotes the diffusion of the zinc element in the base material, and the zinc element is abundantly deposited on the tin film surface. It precipitates and degrades the contact characteristics as described above.

<Analysis of Conventional Products> On the basis of a conventional example, an electrical contact having pure copper as a zinc diffusion barrier layer and an electrical contact having no barrier layer were formed, and a thermal aging test was performed on each of these electrical contacts. By analyzing the diffusion of the constituent elements of the base material by X-ray photoelectron spectroscopy (XPS), the following points were confirmed and assumed.

First, electrical contacts without a barrier layer include:
A tin oxide film is formed on the outermost surface of the tin film, and diffusion of zinc as a constituent element of the base material is suppressed by the tin oxide film,
The diffusion of zinc stops slightly inside the outermost surface of the tin film. This is considered to be because the tin oxide film has a dense structure, and the layer prevents the diffusion and deposition of zinc. Further, also in the electric contact having the barrier layer, a tin oxide film is formed on the outermost surface, and the growth of the alloy layer due to the interdiffusion between tin and pure copper is prevented by the tin oxide film. This is considered that the diffusion of copper is suppressed by the tin oxide film.

[0007]

In view of these points and the fact that tin oxide is an oxide having a high conductivity (10 ⁻⁴ Ωcm), a diffusion barrier is provided between the base material and the tin film. It is thought that the electrical contact with the tin oxide film interposed as a layer can suppress the diffusion of the base metal constituent element even at high temperature by the tin oxide film, but the tin oxide film and the tin film are adhered with sufficient strength In the state, there has been no method for realizing the above structure.

A first object of the present invention has been made in view of the above-mentioned viewpoint, and has a structure in which a tin oxide film is interposed between a base material and a tin film. An object of the present invention is to provide a method for producing a material for electrical contacts, which can form a material for electrical contacts with excellent properties.

A second object of the present invention is to form an electrical contact material having a structure in which a tin oxide film is interposed between a base material and a tin film and having excellent adhesion between the films. In addition, an object of the present invention is to provide an apparatus for manufacturing a material for electric contacts, which can prevent contamination and generation of impurities during formation of the material for contacts.

[0010]

According to a first aspect of the present invention, there is provided a method for manufacturing a material for electrical contacts, comprising the steps of:
A step of preparing a base material substantially made of copper or a copper-based alloy, a step of performing a dry etching treatment with an inert gas on the surface of the base material, and a dry process on an etched region of the base material. The method includes a step of forming a tin oxide film and a step of forming a tin film on the tin oxide film by a dry process.

[0011] To achieve the second object, a second aspect of the present invention is provided.
In the apparatus for producing an electrical contact material according to the above, the first to third chambers are arranged in this order, and the first and second chambers are arranged in this order.
The first and second chambers are communicated by a first communication portion formed between the first and second chambers, and the second and second chambers are formed by a second communication portion formed between the second and third chambers. A housing with which the third chamber is communicated, and a base material substantially made of copper or a copper-based alloy;
The first chamber is transported from the first chamber to the second chamber via the first communication section, and the second chamber is transported from the second chamber to the third chamber via the second communication section. Transport means for transporting, etching means for performing a dry etching process with an inert gas on a surface of the base material transported into the first chamber,
A tin oxide film forming means for forming a tin oxide film by a dry process in an etching region of the base material transported into the second chamber; and a tin oxide film forming means for forming a tin oxide film in the etching region of the base material transported into the third chamber. A tin film forming means for forming a tin film on the tin oxide film by a dry process;

[0012]

According to the method of manufacturing an electrical contact material according to the first aspect, a tin oxide film is formed by a dry process after a base material surface is subjected to a dry etching treatment with an inert gas, and a tin oxide film is formed on the tin oxide film. Since the tin film is formed by a dry process, the structure has a tin oxide film interposed between the base material and the tin film. The tin film adheres to the surface of the base material without any gap, and each film is formed by a dry process, so that a material for electrical contact with excellent adhesion of each film can be formed.

According to the second aspect of the present invention, the housing in which the first to third chambers are arranged in this order and the base material are made of the first, second and third chambers. Transport means for sequentially transporting into the chamber;
Etching means for subjecting the base material conveyed into the chamber to dry etching with an inert gas;
A tin oxide film forming means for forming a tin oxide film by a dry process in an etching region of the base material transferred into the third chamber, and a tin oxide film of the base material transferred into the third chamber, Since a tin film forming means for forming a tin film by a dry process is provided, a tin oxide film and a tin film are formed after the base material surface is cleaned by dry etching. This has a structure in which a tin oxide film is interposed between the base material and the tin film. In addition, the tin oxide film adheres to the base material surface without gaps by the above-described cleaning, and each film is formed by a dry process. While being formed, it is possible to form a material for electrical contact with excellent adhesion of each film, while the base material is not taken out of the housing during the above-mentioned processing, and contact of the base material with the outside air is prevented. As a result, contamination and formation of impurities can be prevented.

[0014]

1 is a block diagram showing a continuous film forming apparatus to which an apparatus for manufacturing a material for electrical contacts according to an embodiment of the present invention is applied, and FIG. 2 is a main part of a transport means 30 provided in the apparatus. FIG. As shown in both figures, this continuous film forming apparatus is an apparatus to which a sputtering method is applied, and includes first to fourth vacuum chambers 24 to 27 and first to third chambers 21 to 23. The housings 20 arranged alternately and the first chamber 21 to the third chamber 2
3, a transporting means 30 for continuously transporting the strip-shaped base material 11 is provided.

Between the first to fourth vacuum chambers 24 to 27 and the first to third chambers 21 to 23, partition plates 24a, 25a, 25a, 26a, 26a, 27 respectively.
a, and each partition plate 24a, 25
Openings 24b, 25b, 26b, 27b provided at the centers of the a, 25a, 26a, 26a, 27a allow the first to fourth vacuum chambers 24 to 27 to communicate with the first to third chambers 21 to 23. Have been. Here, the first communication portion is formed by the second vacuum chamber 25 and the openings 25b, 25b, and the third vacuum chamber 26 and the opening 26 are formed.
The second communication part is constituted by b and 26b.

In the transfer means 30, the first vacuum chamber 24
In the first step, the wound strip-shaped base material 11 is
Chamber 21, opening 25b, second vacuum chamber 25, opening 25b, second chamber 22, opening 26b, third vacuum chamber 26, opening 26b, third chamber 23, opening 27b
Sending means 3 for sending out to the fourth vacuum chamber 27 side through
1 is arranged, and a winding means 32 for winding up the fed base material 11 is arranged in the fourth vacuum chamber 27.

As shown in FIG. 2, support rollers 33 and 34 are provided in the second and third vacuum chambers 25 and 26, respectively, corresponding to the upper and lower surfaces of the base material 11 to be conveyed. The lower support roller 33 is provided in each of the vacuum chambers 25 and 26.
The upper support rollers 34 are rotatably mounted on the upper walls of the vacuum chambers 25 and 26 via mounting members (not shown), respectively, and are vertically movable via mounting members 33a. Can be attached freely. Further, the upper support roller 34 and the vacuum chamber 2
A pressing spring 35 is interposed between the upper walls 5 and 26,
By the urging force of the pressing spring 35, both support rollers 3
The base material 11 is configured to be held between the base material 3 and the base material 34.

The support rollers 33 and 34, mounting members such as a mounting member 33a for supporting them on the inner walls of the vacuum chambers 25 and 26, and the wall of the housing 20 are each made of a conductor such as metal. Thus, the wall of the housing 20 is grounded. Thereby, the support roller 3
The base material 11 sandwiched by the base members 3 and 34 is configured to be grounded via the support rollers 33 and 34 and a roller mounting member.

Returning to FIG. 1, the first chamber 21 has electrodes (anodes) 21a, 21a on its upper and lower walls.
Is attached. Each of the electrodes 21a, 21a is connected to a high-frequency power supply 21e, and the high-frequency power supply 21e causes a high-frequency voltage to be applied between the base material 11 transported in the first chamber 21 in a grounded state and each of the electrodes 21a, 21a. Is applied.

In the second and third chambers 22, 23, target electrodes (cathodes) 22a, 22a, 23a, 23a are mounted on upper and lower walls thereof, respectively. The electrodes 22a, 22a, 23a, and 23a are connected to high-frequency power supplies 22e and 23e, respectively. The base material 11 is transported by the high-frequency power supplies 22e and 23e in the second and third chambers 22 and 23 in a grounded state. When,
High-frequency voltages can be applied to the targets (tin) 22f, 23f set on the electrodes 22a, 22a, 23a, 23a, respectively.

Argon gas introduction means 21b, 22b, 23b for introducing argon gas into the first to third chambers 21 to 23 are connected to the first to third chambers 21 to 23, respectively. An oxygen gas introducing means 22c for introducing oxygen gas is connected to the inside. Further, the first and fourth vacuum chambers 24, 27 and the first to third chambers 21 to 23 are provided with vacuum exhaust means 21d, 2 for evacuating the respective chambers.
2d, 23d, 24d, and 27d are connected.

In order to form an electric contact material in this continuous film forming apparatus, first, target electrodes 22a and 23 are formed.
b, tin (Sn) 22f, 2 as a target respectively
Set 3f. Further, the strip-shaped base material 11 made of copper or a copper-based alloy, for example, made of brass, is housed in the feeding means 31 of the first vacuum chamber 24 in a wound state, and one end of the base material 11 is fed out from the feeding means 31, After being guided to the fourth vacuum chamber 27 through the first to third chambers 21 to 23, the winding means 3
Set to 2.

Subsequently, each of the chambers 21, 22, 23 and each of the vacuum chambers 24-
Evacuate 27 to high vacuum. In this case, the pressures in the first to third chambers 21, 22, 23 are respectively set to P1, P
2, P3, the air pressure in each of the chambers 21, 22, 23 is set so as to satisfy the relational expressions of P1 ≧ P2 and P3 ≧ P2, while the air pressure of the first vacuum chamber 24 is the first chamber. The pressure in the fourth vacuum chamber 27 is set to be about the same as or slightly higher than the pressure in the third chamber 23, while being set to be about the same as or slightly higher than the air pressure of 21. Specifically, P1 is several tens mTorr (millitorr),
2 to 1 to 5 mTorr, P3 to 5 to 20 mTorr
rr (millitorl), and depending on these values, the first
And the atmospheric pressure of the fourth vacuum chambers 24 to 27 is set. As a result, the pressure in the second vacuum chamber 25 is set to a substantially intermediate value between P1 and P2, and the pressure in the third vacuum chamber 26 is set to a substantially intermediate value between P2 and P3.

In this state, the base material 11 is continuously transported from the first chamber 21 to the third chamber 23 at a constant speed by the sending means 31 and the winding means 32, while the argon gas is Introduction means 21b to 23
b, oxygen gas is introduced from the oxygen gas introduction means 22c into the second chamber 22, and the high-frequency power sources 21e to 23e are introduced.
As a result, the base material 11 and the electrode 21a in the first chamber 21 and the base material 11 in the second chamber 22
And the target 22f, and the third chamber 23
, A high-frequency voltage is applied between the base material 11 and the target 23f.

Thus, first, an argon gas plasma is generated between the electrode 21 a and the base material 11 in the first chamber 21, and the argon ions in the plasma are struck against the surface of the base material 11. As a result, impurities such as metal oxides attached to the base material 11 are removed, and the surface of the base material 11 is cleaned (dry etching treatment). As described above, the base material 11 sent into the first chamber 21 is continuously subjected to the etching process, and the second chamber 2
2

In the second chamber 22, the target 2
By the high frequency voltage applied between 2f and the base material 11,
In the meantime, plasma of argon gas and oxygen gas is generated, and argon ions in the plasma collide with the target 22f to strike out target particles (tin particles). Further, the target particles and the oxygen gas plasma are reacted in the gas phase or on the surface of the base material to form tin oxide (Sn).
O ₂ ) is formed, and the tin oxide is deposited on the surface of the base material 11 to form a tin oxide film. In this way, a tin oxide film is continuously formed on the base material 11 sent into the second chamber 22, and then continuously sent into the third chamber 23.

In the third chamber 23, the target 2
The high frequency voltage applied between the base material 3f and the base material 11 generates plasma of the argon gas between the base material 11 and the target, and the argon ions in the plasma collide with the target 23f to strike out target particles (tin particles). Then, the target particles are deposited on the tin film of the base material 11 to form a tin film. In this way, a tin film is continuously formed on the tin oxide film of the base material 11 sent into the third chamber 23, and the base material 11 is sent to the fourth vacuum chamber 27, where the winding means 32.

As described above, the first to third chambers 2
Each of the base materials 11 continuously transferred to the
The etching process and the film forming process are performed in parallel in 1, 2, and 23, and as shown in FIG. An electrical contact material on which the film 13 is formed is formed.

After the etching process and the film forming process are completed up to the end of the base material 11, the above-mentioned electric contact material is taken up by the winding means 3.
When all of the rolls are wound up by the step 2, they are cut into a predetermined shape by a press process or the like in the next step.

The electrical contact material thus formed has a structure in which the tin oxide film 12 is interposed between the base material 11 and the tin film 13, and the tin oxide film has a dense structure. Base material constituent elements (Cu,
The diffusion of Zn or the like to the tin film 13 side is suppressed, and the heat resistance is excellent.

Further, since the surface of the base material 11 is cleaned by sputter etching to remove impurities and then the tin oxide film 12 is formed, the tin oxide film 12 is adhered to the surface of the base material 11 without gaps. And excellent in adhesion between the two.
Moreover, since the tin oxide film 12 and the tin film 13 are formed by a dry process such as a sputtering method,
For example, in comparison with a wet process or the like, in general, the particle diameter of the film-forming (tin oxide film 12, tin film 13) particles can be formed to be small and dense, and the adhesion area of each film 12, 13 to the base material 11, etc. Is large, and the adhesion of the films 12 and 13 is excellent. For this reason, for example, when the electrical contact material is formed into an electrical contact for a switch, a terminal, or the like, even if it undergoes plastic deformation, film peeling does not occur.
Furthermore, since each of the films 12 and 13 can be formed in a dense structure, also in this respect, the diffusion of the constituent elements of the base material can be more reliably suppressed.

Further, the first to third chambers 21 to 2
3 are arranged side by side, and the base material 11 is continuously subjected to the etching process and the film forming process without being brought into contact with the outside air, so that the generation of impurities such as oxides and the mixing of impurities during these processes are prevented. You. Further, in the case where the etching process and the film formation process are performed under reduced pressure as in this embodiment, the pressure P2 of the second chamber 22 is changed to the pressure P1, P3 of the first and third chambers 21 and 23. , The gas (especially active oxygen) in the second chamber 22 is
1 and 23 are prevented from being mixed in the first chamber 21 during the etching process and in the third chamber 23.
Generation of impurities such as oxides can be prevented during the formation of a tin film in the inside.

In this embodiment, since the respective processes are performed in parallel by the first to third chambers 21 to 23, the production efficiency is improved.

Further, since inexpensive tin is used as a coating material for the base material 11, the cost can be reduced.

In the above embodiment, the case where the tin oxide film is formed directly on the base material has been described. However, as shown in FIG. 4, copper base made of pure copper is wet-processed on base material 51 made of brass. After the layer (zinc diffusion barrier layer) 54 is formed, the tin oxide film 52 and the tin film 53 may be formed on the copper layer 54 by the same method as in the above embodiment.

In such a material for electrical contacts, the base material 51
Diffusion of the zinc element is caused by the barrier layer 54 and the tin oxide film 5.
2, and the interdiffusion between copper of the barrier layer 54 and tin of the tin film 53 is suppressed by the tin oxide film 52. Further, the copper layer 54 made of pure copper also has a function of adjusting the underlying substrate. By forming the copper layer 54, the surface thereof is flattened, and the adhesion of the tin oxide film 53 is further improved.

In the above embodiment, the tin oxide film and the tin film are formed by a dry process such as a sputtering method. However, other dry processes, such as a vacuum deposition method, an ion beam mixing method, and an ion plating method, are used. The tin oxide film and the tin film can also be formed by a physical vapor deposition method such as a chemical vapor deposition method, a chemical vapor deposition method such as a thermal CVD, a plasma CVD, a photo CVD, or a plasma polymerization method.

In this case, when the vapor deposition method or the ion beam mixing method is used, the evaporation source is set to the chambers 22 and 23.
The film can be formed more efficiently when it is installed on the side wall or the lower wall than when it is installed on the upper wall.

Although dry etching using an inert gas has been described by taking sputter etching as an example, other ion beam etching using, for example, an inert gas can also be used.

Although a high-frequency voltage is applied between the electrodes 21a, 22a, and 23a and the base material 11, a DC voltage may be applied.

In the above embodiment, the delivery means 31 and the winding means 32 of the transport means 30 are arranged inside the housing 20, but the delivery means 31 and the winding means 3 are arranged.
2 may be arranged outside the housing 20.

Although the belt-shaped base material 11 is used, a linear base material may be used. In that case, after forming the tin oxide film and the tin film in the same manner as described above, a cutting process and a pressing process may be performed. In addition, the above-described etching process and film forming process may be performed by sequentially passing a small-piece base material cut in advance into the first to third chambers.

Further, in the above-described embodiment, the case where one tin oxide film is formed has been described, but two or more tin oxide films may be formed.

Also, a target 22 for forming a tin oxide film is provided.
Although metal tin is used as f, tin oxide may be used.

Hereinafter, for reference, an experimental example regarding the heat resistance and the like of the electrical contact material formed based on the above-described embodiment will be shown.

<Experimental Example> A tin oxide film (SnO ₂ ) of 0.2 μm was formed on one surface of a base material made of brass (Cu, Zn) in the same manner as in the first embodiment, and further thereon. An electrical contact material was formed by forming a tin film on the substrate. And the contact resistance value with respect to the load of the contact material was measured. Further, after the electrical contact material was heat-treated at 200 ° C. for 24 hours, the contact resistance value with respect to the load was measured, and the element distribution in the contact material was measured by X-ray photoelectron spectroscopy (XPS). FIG. 5 shows the contact resistance change before the heat treatment, FIG. 6 shows the contact resistance change after the heat treatment, and FIG. 7 shows the element distribution in the material by XPS. In this case, FIG.
In the graphs of FIG. 6 and FIG.
m), and the vertical axis indicates contact resistance (ohm). In the graph of FIG. 7, the abscissa indicates the etching time (minute) corresponding to the depth position from the surface, and the ordinate indicates the abundance (%) of each element measured by XPS. Open squares indicate copper, solid black circles indicate zinc, x indicates tin, and white circles indicate oxygen.

As a reference example, the conventional method
That is, the surface of the base material made of brass was coated with a tin film by an electrolytic plating method to form an electrical contact material. Then, the change in contact resistance with respect to the load of the contact material was measured.
After heating the electrical contact material at 200 ° C. for 24 hours, measurement of change in contact resistance with respect to load and XPS
And the distribution of elements in the material was measured. FIG. 8 shows the contact resistance change before heat treatment, and FIG. 9 shows the contact resistance change after heat treatment.
The element distribution by XPS is shown in the graph of FIG.

First, comparing the changes in contact resistance, the contact material according to the embodiment (FIGS. 5 and 6) generally has a lower contact resistance value than the conventional material (FIGS. 8 and 9). It can be seen that the contact characteristics are excellent. Furthermore, while little variation was observed in the contact material of the example, much variation was observed in the conventional contact material, indicating that the quality of the contact material of the example was stable.

Further, in the contact material according to the embodiment, the respective contact resistance values after the heat treatment (FIG. 6) hardly change compared with those before the heat treatment (FIG. 5), and they are excellent in heat resistance. I understand. On the other hand, in the conventional example, when the respective contact resistance values after the heat treatment (FIG. 9) are compared with those before the heat treatment (FIG. 8), the variation is large and high, and the heat resistance is inferior. .

As for heat resistance, FIG. 7 and FIG.
Also from the element distribution of 0, it can be determined that the electrical contact material of the example is excellent.

That is, as shown in FIG. 7, in the electrical contact material according to the embodiment, the etching time is from the surface of the tin film of 0 minute to the boundary between the tin film and the base material in the vicinity of 15 minutes, that is, in the tin film. Contains a large amount of a tin element (marked with x) and almost no copper element (open square) or zinc element (closed circle) as a base material constituent element. This is presumably because the diffusion of the constituent elements of the base material was suppressed, and the precipitation of the zinc element on the surface of the tin film and the formation of an alloy of copper and tin were both prevented. As described above, the electric contact material according to the embodiment has a temperature of 200 ° C.
It can be seen that even at a high temperature, the diffusion of the base material constituent element which causes the deterioration of the contact characteristics can be suppressed and the heat resistance is excellent.

On the other hand, in the conventional contact material shown in FIG. 10, first, the etching time is about 0 minute on the tin film surface.
It can be confirmed that the zinc element (solid circle) as a constituent element of the base material is already present together with oxygen (open circle). This is considered to be because zinc element diffused from the base material diffuses toward the tin film side and precipitates on the tin film surface to form zinc oxide having low conductivity. Further, conventionally, the etching time is zero.
It is confirmed that a large amount of the copper element (open squares) is present together with the tin element (marked by x) in the tin film and the boundary portion between the base film and the tin film at about 18 minutes to 18 minutes. This is considered to be due to the fact that a large amount of copper diffuses from the base material into the tin film, forming an alloy having high hardness with copper and tin. Thus, it can be seen that the conventional material for electric contacts has a remarkable diffusion of the base material constituent element which causes the deterioration of the contact characteristics at a high temperature, and is inferior in heat resistance.

When the appearance of the contact material according to the example was visually observed before and after the heat treatment, the tin oxide film and the tin film were not peeled at all, and the adhesion of each film was excellent. Was confirmed.

[0054]

As described above, according to the method for manufacturing an electrical contact material according to the first aspect, a tin oxide film is formed by a dry process after performing a dry etching process with an inert gas on a surface of a base material. In addition, since a tin film is formed on the tin oxide film by a dry process, a tin oxide film is interposed between the base material and the tin film, and the surface of the base material is dry-etched. Is cleaned, the tin oxide film adheres to the surface of the base material without gaps, and each film is formed by a dry process, whereby a material for electrical contact with excellent adhesion of each film can be formed. Is obtained.

According to the second aspect of the present invention, the housing in which the first to third chambers are arranged in this order and the base material are divided into the first, second and third chambers. Transport means for sequentially transporting into the chamber;
Etching means for performing a dry etching process with an inert gas on a base material disposed in the first chamber;
A tin oxide film forming means for forming a tin oxide film by a dry process in an etching region of the base material transferred into the third chamber, and a tin oxide film of the base material transferred into the third chamber, A tin film forming means for forming a tin film by a dry process, the tin oxide film and the tin film are formed after the surface of the base material is cleaned by a dry etching process, whereby the base material and the tin film are formed. The structure has a structure in which a tin oxide film is interposed between it and the above-mentioned cleaning, and the tin oxide film adheres to the surface of the base material without any gaps. While it can form electrical contact materials with excellent properties,
During the above-described processing, the base material is not taken out of the housing, and the base material is prevented from coming into contact with the outside air, so that the second effect of preventing entry and generation of impurities can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a continuous film forming apparatus to which an apparatus for manufacturing a material for electrical contacts according to an embodiment of the present invention is applied.

FIG. 2 is a side view showing a main part of a transport unit mounted on the continuous film forming apparatus.

FIG. 3 is an enlarged sectional view of a main part showing a material for an electric contact manufactured by the continuous film forming apparatus.

FIG. 4 is an enlarged sectional view of a main part showing a material for an electric contact of a modified example formed based on the present invention.

FIG. 5 is a graph showing a change in contact resistance of a material for an electric contact before heat treatment based on an example.

FIG. 6 is a graph showing a change in contact resistance after heat treatment of an electrical contact material according to an example.

FIG. 7 shows X after heat treatment of the electrical contact material according to the embodiment.
It is a graph which shows the element distribution by PS.

FIG. 8 is a graph showing a change in contact resistance of an electrical contact material based on a conventional example before heat treatment.

FIG. 9 is a graph showing a change in contact resistance after heat treatment of an electrical contact material based on a conventional example.

FIG. 10 is a graph showing element distribution by XPS after heat treatment of a material for electric contact based on a conventional example.

[Explanation of symbols]

 11,51 Base material 12,52 Tin oxide film 13,53 Tin film 20 Housing 21,22,23 First, second and third chamber 30 Transport means

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI C23C 14/16 C23C 14/16 Z 28/00 28/00 B C23F 4/00 C23F 4/00 A H01H 1/04 H01H 1 / 04 E 11/04 11/04 F (58) Fields investigated (Int. Cl. ⁷ , DB name) C23C 14/00-14/58 C23C 28/00 C23F 4/00 H01H 1/04 H01H 11/04

Claims (2)

(57) [Claims] A step of preparing a base material substantially made of copper or a copper-based alloy; a step of performing a dry etching process with an inert gas on a surface of the base material; and an etched region of the base material. Forming a tin oxide film by a dry process; and forming a tin film on the tin oxide film by a dry process. 2. A method according to claim 1, wherein the first and second chambers are arranged in this order, and the first and second chambers are communicated by a first communication portion formed between the first and second chambers. And a housing in which the second and third chambers are communicated by a second communication portion formed between the second and third chambers, and a base material substantially made of copper or a copper-based alloy. Transporting from the first chamber to the second chamber via the first communication portion, and from the second chamber to the third chamber via the second communication portion. Transport means for transporting the base material to the surface of the base material transported into the first chamber;
Etching means for performing a dry etching process using an inert gas; and tin oxide film forming means for forming a tin oxide film by a dry process in an etching region of the base material transported into the second chamber. And a tin film forming unit for forming a tin film by a dry process on the tin oxide film of the base material transported into the third chamber.