JP2004152559A - Electronic component and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the creeping of solder to a contact part in an electronic component such as a connector or a switch having a terminal soldered with the contact part. <P>SOLUTION: Surface plating 3 is conducted on a base material 1 or undercoat plating 2 on the base material, one part of the plated surface is heat-treated by using a laser 6 or the like, the mutual thermal diffusion of the base material or a undercoat plating film with a surface plating film is conducted, a reformed layer 5 is formed of the base material or the undercoat plating film and the surface plating film, and the reformed layer 5 is used as a solder creeping preventing region. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides an electronic component such as a connector or a switch having a contact portion and a terminal portion to be soldered, in which an area for preventing solder from creeping up on a terminal portion creeping up on a surface plating layer formed as a contact portion is provided. A new method of forming and an electronic component having such a prevention zone.
[0002]
[Prior art]
Conventionally, when a surface treatment is performed so as to have a contact portion and a terminal portion to be soldered in a material for an electronic component such as a connector or a switch, which functions by performing the surface treatment, for example, FIGS. As shown in FIGS. 10, 11, and 12 (the drawings used here are shown in the cut surfaces of the electronic component materials without bending in any of FIGS. 1 to 12), copper alloys and iron A base material nickel plating 2 is selectively or entirely applied to a material 1 such as an alloy, and a gold plating 3 is selectively applied thereon as a surface plating for a contact portion. In general, the solder plating 4 is applied, and a base plating portion is left therebetween, and this portion is generally used as a solder rising prevention region 5.
Some electronic component materials are plated before molding, while others are plated after molding.
In addition to nickel plating, there are also examples of electroless nickel plating, etc. applied as the base plating, and if the base material is iron-based alloy, nickel-based alloy, stainless steel, etc., omit the base plating There is also.
In addition to gold plating, surface plating for the contact portion may be plated with palladium, palladium alloy, silver, tin, solder (tin-lead alloy), tin-copper alloy, or the like.
In addition to the above, there are examples in which the surface plating for the terminal is plated with palladium, a palladium alloy, silver, tin, tin-copper alloy, or the like.
[0003]
Selective plating methods include using a jig to shield unnecessary plating from the plating solution, masking with an adhesive tape, immersing only the necessary parts in the plating solution, and plating. Is used.
However, in the method of using a jig to shield unnecessary plating from the plating solution, the adhesion between the plating material and the jig is not perfect, so the plating solution slightly penetrates between the jig and the plating material at this part. However, bleeding of the plating occurs in the unnecessary portion of the plating (partial plating occurs).
In a method of masking by attaching an adhesive tape to a material, since the tape material is generally a plastic film, the tape expands and contracts due to the tension at the time of masking, causing errors in width and position. Further, since the plastic film is weak in strength, it is difficult to stably attach the plastic film having a width of about 1 mm to the material and mask it.
In the method of immersing only a necessary portion in a plating solution to perform plating, since the surface tension of the solution exists, the plating solution is sucked into the liquid surface portion of the plating material, and plating bleed of 2 mm or more occurs.
Therefore, in these plating methods, there is always an error of about 1 to 2 mm in the plating position accuracy, and a minimum of about 1 to 2 mm width is required as the remaining portion of the base nickel plating required as the solder drip prevention area. Become.
However, recently, electronic components have become lighter and thinner and smaller. For example, connectors having a total length of about 1 mm have also appeared, and the width of the solder drip prevention area is required to be 1 mm or less, and in some cases 0.1 mm or less. It has become.
That is, it is becoming impossible for such a conventional method to form a solder wicking prevention region satisfying the requirements.
[0004]
In order to solve this problem, it is conceivable to apply a photosensitive resin to the plating surface after nickel plating and mask the unnecessary portion by a pattern forming method.
However, this method is not suitable for the surface treatment of an electronic component in which cost is regarded as important due to the necessity of a complicated process like the production of a printed circuit board.
[0005]
As one measure of this solution, after the base nickel plating is applied to the material, the surface is plated with gold, and after plating, the surface of the portion where the prevention of solder rising is required is oxidized to prevent the solder rising. .
However, in this method, it is difficult to form an oxide layer because gold plated as a contact metal is not oxidized.
Further, the energy applied to promote oxidation of the nickel plating surface of the base increases, which causes a problem that the thermal influence on the contact plating portion around the solder drip prevention surface is increased. (For example, see Patent Document 1)
[0006]
As another solution, the material is plated with nickel under the surface, then the surface is plated with gold, and then the surface of the part that needs to be protected from solder erosion is mechanically ground or polished, electric discharge or electron beam processing, laser It is also practiced to selectively remove by applying a processing technique to expose the underlying nickel surface.
However, in this method, it is difficult to accurately remove the thin surface gold plating film, and usually, the thickness of the underlying nickel plating is 0.5 to 2.5 μm, and the thickness of the surface gold plating is 0.03 to 0.5 μm. The subsequent metal surface may be roughened due to the grinding, or the material metal may be exposed.
Further, there arises a problem that the metal in the removed portion scatters or accumulates in the peripheral portion and may contaminate the gold plating film on the surface of the contact portion. (For example, see Patent Document 2)
[0007]
[Patent Document 1]
JP-A-8-213070 (page 3, FIG. 1)
[Patent Document 2]
JP-A-2002-203627 (Page 4, FIG. 5)
[0008]
[Problems to be solved by the invention]
In a connector or a switch having a contact portion and a terminal portion to be soldered, a region for preventing the solder from creeping up on the surface plating layer formed as the contact portion has a width of about 1 mm or less, and has a width of 0.1 mm or less. The challenge is to make it with an accuracy of about 1 mm.
However, the conventional method cannot solve the problem as described in 0002 to 0006.
In other words, in the method of selectively forming a non-surface-plated portion of 0002 to 0004 and using the portion as a solder-up prevention region, it is possible to satisfy the problem of accuracy of reducing the width of the prevention region to about 0.1 mm. Can not.
With the method of oxidizing surface plating of 0005, it is difficult to oxidize gold, which is often used as a contact surface plating metal.
In the method in which a part of the surface is removed after the surface plating of 0006, and this surface is used as a solder wicking prevention area, it is difficult to control the width and thickness of the part to be removed, and material exposure and surface roughness of the solder wicking prevention area occur. And the problem that the removed metal contaminates the surface of the contact portion near the solder wicking prevention region occurs.
[0009]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION The present invention provides an electronic component and a method for solving the above-mentioned solder drip problem.
That is, in the surface treatment of electronic component materials such as connectors and switches having contact parts and terminal parts to be soldered, surface plating is applied to the material, and then a part of the plating surface is heat-treated, so that the material and the surface plating By thermally diffusing the film with each other and forming a solid solution, alloying, and intermetallic compounding of both metals, a reformed layer is formed by the material and the plating film. It is characterized by having.
[0010]
In the surface treatment of the electronic component material, a base plating and a surface plating are performed on the material, and then a part of the plating surface is heat-treated, whereby the base plating film and the surface plating film are mutually thermally diffused, and both metals are diffused. A solid solution, alloying, and intermetallic compounding form a modified layer of a base plating film and a surface plating film, and this portion is used as a region for preventing solder from rising to the contact portion.
[0011]
Nickel plating is applied as a base plating, followed by gold plating as a surface plating, and then a part of the plating surface is heat-treated by irradiating thermal energy such as a laser. A modified layer having a wide width is formed, and this portion is used as a region for preventing solder from rising to a contact portion.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to FIGS.
When surface treatment is performed so as to have a contact portion and a terminal portion to be soldered in a material for electronic components such as connectors and switches that exhibit a function by performing the surface treatment, first, FIGS. As shown in FIG. 5, an underlying nickel plating 2 is selectively or entirely applied to the material surface 1, and a surface gold plating 3 is selectively or entirely applied thereto. Generally, the thickness of the underlying nickel plating film is about 0.5 to 2.5 μm, and the thickness of the surface gold plating is about 0.03 to 0.5 μm.
After plating, as shown in FIG. 2, FIG. 4, and FIG. 6, thermal energy 6 such as a laser is locally applied to a part of the surface gold plating surface to form a fine width of 1 mm to 0.01 mm. Then, the surface gold plating film and the underlying nickel plating film are uniformly alloyed by thermal diffusion.
At this time, since the underlying nickel plating film is thicker than the surface gold plating film, a solder rising prevention surface 5 having a nickel appearance is formed on a heat energy irradiation portion such as a laser.
One of the gold-plated surfaces other than the heat energy irradiating part is used as a contact part 3 ', and the other is used as a terminal part 4' to be soldered.
[0013]
Next, an example of the experiment performed is shown.
Phosphor bronze material with a board thickness of 0.1 mm and a material width of 29.5 mm is plated with a 1.5-μm-thick nickel plating over the entire surface, and a gold plating is selectively applied on the surface with a width of 3 mm and a thickness of 0.2 μm. Then, the sample of the conceptual diagram 3 was produced.
After the plating, a Nd: YAG laser beam having an oscillation wavelength of 355 nm and an average output of 3 w was irradiated onto the sample surface at a scanning speed of 50 mm / sec at a scanning speed of 50 mm / sec along a position 1 mm from the end of the gold plating width. The gold color on the sample surface of the irradiated part has a width of 0.3 mm and has a nickel appearance along the scanning direction of the laser beam, and the width is constant. A contact portion 3 'having a gold plating appearance of .85 mm, a modified portion 5 having a nickel plating appearance of 0.3 mm width, and a terminal portion 4' having a gold plating appearance of 1.85 mm width were obtained. .
In this experiment, in FIG. 4, the 3 ′, 5, 4 ′ surfaces did not have irregularities and did not deteriorate in surface properties due to laser beam irradiation.
Next, when this was subjected to elemental analysis using an EPMA (Electron Beam Microanalyzer), the laser beam irradiated part had a nickel appearance, but from this part the gold element was detected with a strength not much different from that of the non-irradiated part. The surface gold plating film was not removed by the laser beam irradiation, indicating that the underlying nickel plating film and the surface gold plating film were thermally diffused with each other to form a nickel-gold alloy layer with a high nickel ratio, The state of FIG. 4 was confirmed by elemental analysis.
When the 4 ′ portion of FIG. 4 manufactured in this manner was soldered, the portion having a width of 0.3 mm modified by laser beam irradiation acts as a solder rising prevention region 5, and the solder creeps up to the contact portion 3 ′. The effect of preventing was confirmed.
[0014]
When irradiating a laser or the like, it is possible to irradiate only one surface of the plating surface, or to irradiate all surfaces (four surfaces) of the plating surface. Of course, it is also possible to manufacture not only one but also a large number of solder rising prevention areas modified by irradiation.
As a result of the experiment, it was found that when a laser beam was used, those having a wavelength in the visible light portion to the ultraviolet portion were more easily absorbed by the metal surface than those in the infrared portion, and were suitable for surface modification.
Since the laser beam can be focused by a lens at a single wavelength, a partial heat treatment with a narrow width of 1 mm or less and about 0.01 mm is possible.
In this method, the surface direction and the depth direction of the plating surface can be freely selected by adjusting the beam diameter and the irradiation time, so that it can be applied to various requirements with different specifications.
[0015]
Although the embodiment of the invention has been described with reference to the underlying nickel plating and the surface gold plating, the underlying nickel plating may be omitted in some cases.
In this case, as shown in FIG. 7, after performing gold plating directly on the material, as shown in FIG. 8, heat energy 6 such as a laser is locally applied to a part of the surface gold plating surface. Then, the surface gold plating film and the material are formed into a solid solution, alloyed, and intermetallic compound by thermal diffusion with a fine width of 1 mm to 0.01 mm.
Of course, the underlying plating on the material is not limited to nickel, and electroless nickel or other plating can be used.
The plating of the contact portion on the surface is not limited to gold, and plating of palladium, palladium alloy, silver, tin, etc. can also be used.
[0016]
As described above, the solder wicking prevention surface 5 surface-treated according to the embodiment of the present invention maintains the same plane as the 3 ′ and 4 ′ portions, has no unevenness on the material surface, and is formed by thermal diffusion of gold and nickel. 9 is an alloy surface of the modified layer, which has more nickel than gold, so that the appearance is a nickel color that can be visually discriminated, and this portion acts as a solder wicking prevention surface. By irradiating thermal energy such as a laser with the function more than the conventional technology shown in FIGS. 10, 11 and 12, the area for preventing solder drip is extremely narrow as compared with the conventional product. This has the effect that the position accuracy is outstanding.
[0017]
【The invention's effect】
According to the present invention, in a connector or switch electronic component having a contact portion and a terminal portion to be soldered, a material or a base plating film such as nickel and a surface plating film such as gold are irradiated with thermal energy such as laser. To form a modified layer by solid-solution, alloying, and intermetallic compounding of both metals to prevent the solder from creeping up at this point.
In addition, the solder rising prevention area (prevention surface) can be extremely narrowed to about 0.1 mm with no irregularities on the surface by irradiating thermal energy such as a laser, and the prevention area can be formed. Selection of a part is easy, and its position can be controlled with high accuracy.
It is also effective in visually confirming the discoloration of the modified layer, which is the solder drip prevention area, in terms of processing confirmation.
These techniques are also effective for improving mass productivity required for processing fine electronic components.
[Brief description of the drawings]
FIG. 1 is a view before irradiation with heat energy after plating FIG. 2 is an example of a state after irradiation with heat energy such as a laser in FIG. 1 FIG. 3 is a view before irradiation with heat energy after plating FIG. Example of state after irradiating thermal energy such as laser to plate [Fig. 5] Figure before irradiating heat energy after plating [Fig. 6] Fig. 5 Example of state after irradiating heat energy such as laser [Fig. 7] Heat after plating FIG. 8 shows a state before irradiation with thermal energy such as a laser in FIG. 7; FIG. 9 is a diagram illustrating a conventional example; FIG. 10 is a diagram illustrating a conventional example; FIG. FIG. 12 illustrates a conventional example. [Description of References]
Reference Signs List 1 Material such as copper alloy and iron alloy 2 Base nickel plating film 3 Surface gold plating film 3 'Gold surface for contact part after heat treatment 4 Surface gold or solder plating film 4' Gold surface for soldering terminals after heat treatment 5 Solder finish Prevention area 6 Heat energy irradiation part such as laser

Claims (6)

An electronic component such as a connector or a switch that has a contact part and a terminal part to be soldered. The material is subjected to surface plating, and then a part of the plating surface is heat-treated to allow the material and the surface plating film to interact with each other. A method for producing an electronic component, comprising: forming a modified layer of a material and a plating film by heat diffusion to form a region for preventing solder from rising to a contact portion. An electronic component, such as a connector or a switch, having a contact portion and a terminal portion to be soldered, which is provided with a base plating and a surface plating on a material, and then a part of the plating surface is subjected to a heat treatment, so that a base plating film and a surface are formed. A method for manufacturing an electronic component, comprising: forming a modified layer of a base plating film and a surface plating film by thermally diffusing a plating film with each other; Nickel plating as a base plating, then gold plating as a surface plating, and then heat treatment by irradiating thermal energy such as laser to a part of the plating surface, thereby modifying the base nickel plating film and the surface gold plating film 3. The method for manufacturing an electronic component according to claim 2, wherein a layer is formed, and this portion is used as a region for preventing solder from rising to the contact portion. An electronic component such as a connector or a switch that has a contact part and a terminal part to be soldered. Surface plating is applied to the material, and a part of the plating surface is heat-treated to form the material and the surface plating film. An electronic component characterized by forming a modified layer of a material and a plating film by thermally diffusing each other, and using this portion as a region for preventing solder from rising to a contact portion. An electronic component, such as a connector or a switch, having a contact portion and a terminal portion to be soldered, and a base plating and a surface plating are applied to a material, and a part of the plating surface is heat-treated to form a base plating film. An electronic component, wherein a surface plating film is mutually thermally diffused to form a modified layer of a base plating film and a surface plating film, and this portion is used as a region for preventing solder from rising to a contact portion. It has nickel plating as a base plating and gold plating as a surface plating. By irradiating thermal energy such as laser to a part of this plating surface, the base nickel plating film and the surface gold plating film are mutually thermally diffused. 6. The electronic component according to claim 5, wherein a modified layer comprising a base nickel plating film and a surface gold plating film is formed, and this portion is used as a region for preventing solder from rising to a contact portion.

Images