JP2850189B2 - Jig for plating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating jig used for electroplating lead pins and the like of a package for mounting a semiconductor (hereinafter, simply referred to as a package). The present invention relates to a plating jig (hereinafter, also simply referred to as a jig) made of a metal plate-like member used for conducting electroplating on various portions of a lead pin or the like by conducting from a plurality of lead pins.

[0002]

2. Description of the Related Art In the manufacture of a plug-in type package represented by a pin grid array (PGA) type, 42 alloy (Fe-Ni
Alloy) and Kovar (Fe-Ni-Co alloy) are soldered together with a number of lead pins (terminals for external connection), and then the lead pins and other parts of the package are used to improve corrosion resistance and electrical conductivity. Ni or Au is electroplated.

A plating jig for this purpose is disclosed in
Various techniques have been proposed, such as those described in Japanese Patent No. 286131. According to this publication, a lead pin (hereinafter, also simply referred to as a pin) of a package body is provided on a conductive metal foil plate.
A radial slit is drilled in accordance with the pitch of the slit, and a pin is pushed into the center of the slit from its axial direction and pressed against the metal part of the opening diagonal at the center of the slit to perform electroplating. (Hereinafter simply referred to as plating), necessary continuity is obtained, and this state is immersed in a plating solution (electrolysis) tank, and a necessary setting such as connecting a plating jig to a cathode is performed. The plating is applied to all parts of the package at once.

[0004]

Problems to be Solved by the Invention Japanese Patent Laid-Open No. 4-28613
The jig described in Japanese Patent Publication No. 1 is designed to conduct electricity by pushing a pin into an opening, but since the opening is a radial slit, the number of contact points with the pin is three or more in the circumferential direction. This portion remains as a non-plated portion after plating. Therefore, there is a problem that a portion that is not plated, that is, a non-plated area is large, which causes a reduction in corrosion resistance and, consequently, a reduction in quality and performance of the package.

In the above-mentioned conventional jig, the tip of the pin is pressed from above into the center of a slit at a predetermined pitch and press-fitted. However, the pin has variations (errors) such as inclination and the like. However, it is difficult to match the tips of the large number of pins with the centers of the individual slits, and the setting (positioning) is troublesome. Furthermore, it is necessary to prevent conduction (plating) failure due to some of the pins not being able to contact the jig. However, if the pin is not deep enough to be pressed close to the tip, In some cases, non-contact may occur during the plating process due to irregularities in pin length and the like. Therefore, the pin must be pressed in deeply from its tip. On the other hand, when the pin is pulled out in the axial direction after plating, the edge of the opening scrapes the plating on the outside of the pin, so that there is a problem that the plating surface is easily damaged. An object of the present invention is to solve these various problems of the conventional jig.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a plating jig used for electroplating lead pins of a package for mounting a semiconductor on a metal. A plurality of openings corresponding to the arrangement of the lead pins are formed in the plate member, and each of the openings has a play insertion hole through which the lead pin can be freely inserted, and a play insertion hole through which the lead pin is inserted. A press-fitting hole which is press-fitted by being loosely inserted into the hole and moved in the radial direction, and further comprising an opening edge on at least one side of the press-fitting hole along the press-fitting direction of the lead pin, wherein Is smaller than the thickness of the plate-like member. In this case, it is preferable that the press-fitting hole is formed in a slit shape, and its width is smaller than the outer diameter of the lead pin and is substantially constant, or the lead pin is press-fitted into a smaller tapered shape. Further, in these plating jigs, a hole is provided outside the opening edge of at least one side of the press-fitting hole along the press-fitting direction of the lead pin so that the opening edge can be bent outward and deformed. Alternatively, it is preferable that at least one opening edge of the press-fitting hole along the direction of press-fitting of the lead pin is formed in a cantilever shape that can be bent outward and deformed.

[0007]

In the plating jig of the present invention described above, each lead pin is loosely inserted into the play insertion hole in the opening, and in this state, the lead pin is fixed to the play insertion hole by fixing the plate member or the like. When moving in the direction of the press-fit hole in the radial direction, the respective lead pins are pushed into the press-fit hole from the radial direction,
Press-fit. As a result, each lead pin is pressed or bites against the opening edge of the press-fitting hole on its side, and is electrically connected to the plating jig. Moreover, since the thickness of the contact portion of the press-fitting hole on at least one side along the press-fitting direction of the lead pin and in contact with the lead pin is smaller than the thickness of the plate-like member, the thickness of the press-fitting hole is reduced. It has good stickiness and firmly bites, so that reliable conduction is ensured. Therefore, thereafter, by connecting the plating jig to the cathode and performing electroplating in the plating bath under the plating jig, predetermined portions of the package such as lead pins can be plated. Then, after plating, each lead pin may be relaxed by applying an external force opposite to that when the lead pin is pressed into the press-fitting hole, and the package may be separated from the plating jig by pulling out the package in the axial direction of the pin. In the plating jig according to the present invention, a hole is provided outside the opening edge of at least one side of the press-in hole along the press-in direction of the lead pin so that the opening edge can be bent outward and deformed. Or, when at least one opening edge of the press-fitting hole along the press-fitting direction of the lead pin is formed in a cantilever shape that can be bent outwardly, the opening edge is deformed outwardly. The pin can be easily pressed or loosened.

[0008]

Next, an embodiment of the present invention will be described in detail with reference to FIGS. The plating jig 1 of this embodiment is made of 42 alloy (Fe—Ni alloy), is made of a thin plate member (thickness: about 0.3 mm) 2 having a spring property, and has a cavity for accommodating a semiconductor element in the package 11. (Not shown), a central portion is punched out into a substantially square shape, and the whole is formed in a rectangular shape, and substantially the entire surface thereof has openings 3 having the following shapes corresponding to the arrangement of the pins 13, 13.
A large number of holes 3 are formed by etching (or press punching) at predetermined pitches in the vertical and horizontal directions.

That is, each of the openings 3 has a play insertion hole 4 for receiving each of the pins 13 in a freely inserted manner corresponding to the arrangement of the lead pins 13.
And a press-fit hole 5 into which the pin 13 is loosely inserted into the play insertion hole 4 and moved in the radial direction of the pin 13 (right in FIG. 1). However, in the present embodiment, the loose insertion hole 4 is substantially circular with an inner diameter larger than the outer diameter (0.41 mm) of the pin 13, and the press-fit hole 5 is located on one side of the loose insertion hole 4 (right side in FIG. 1). On the other hand, the width W is smaller than the outer diameter of the pin 13 and is formed in a slit shape with a substantially constant width, and the entire opening 3 has a keyhole shape. However, in this example, the upper edge of the opening edge (both sides) 6a in the press-fit hole 5 along the press-fit direction of the pin 13 is chamfered by the inclined surface k to form a knife-edge shape, and the contact portion with which the pin 13 contacts The thickness t of 6b is extremely reduced relative to the thickness (plate thickness) T of the plate member 2 (see FIGS. 2 to 4). Incidentally, in this example, the inner diameter of the play insertion hole 4 of the opening 3 is 1.2 mm, and the width W of the opening edges 6 a, 6 a of the press-fitting hole 5 is 0.1 mm larger than the outer diameter of the pin 13.
It is set smaller by 01 to 0.1 mm. Although not shown in the overall view of FIG. 1, in this example, as shown in the enlarged view, the opening edge 6 of the press-fit hole 5 is provided on both sides of each of the openings 3 and 3.
Substantially trapezoidal holes 7, 7 are formed through windows so that the opening edges 6 a, 6 a on both sides along the press-fitting direction of the pin 13 on the outside of the pins a, 6 a are bent outward. The holes 8 provided along both sides (left and right in FIG. 1) of the plate member 2 are
This is for fixing the jig 1 at the time of press-fitting the pin 13.

Next, a case where conduction is performed using the plating jig 1 will be described. First, as shown in FIG. 5, the tip of the pin 13 of the package 11 faces the play insertion hole of the opening with respect to the jig 1, each pin 13 is loosely inserted into each play insertion hole, and the package 11 is placed in the jig. Set (position) to 1. Then, while the jig 1 is fixed, the package 11 is moved in the lateral direction as illustrated below.

That is, first, as shown in FIGS. 6A and 7A, a slider which is provided with a play insertion hole 24 having the same arrangement and size as the play insertion hole 4 of the jig 1 and which slides in the lateral direction. 21
Is placed on a base (not shown), and the jig 1 is placed on the base so that the play insertion holes 4 and 24 substantially coincide with each other, and the jig 1 is fixed by the fixing means (not shown) using the holes 8 and 8 on both sides. The package 11 is fixed to the base, and the package 11 is set such that each pin 13 is substantially at the center of each play insertion hole 4. Next, the slider 21 is moved to the press-fitting hole 5 side of the opening 3 of the jig 1 (the right side in FIGS. 6 and 7). Then, one side (left side) of the play insertion hole 24 of the slider 21 hits the left side of the tip of the pin 13 (see FIGS. 6B and 7B). When the pin 13 is further moved in the same direction by a predetermined amount, the pin 13
And pressed into the press-fit hole 5 (FIG. 6C).
FIG. 7 (C)). At this time, since the opening edge 6a of the press-fitting hole 5 has the holes 7, 7 on the outside, the opening edge 6a is slightly spread outward by the spring action. Thus, the opening edges 6a, 6a of the press-fitting hole 5 in which two points on both sides of the pin 13 are formed in a slit shape,
That is, by being pressed against the knife edge-like contact portions 6b, 6b, extremely highly reliable conduction is secured. The difference in the position (height) of the tip surface of the pin 13 in FIG. 6 indicates an error in the pin length.

After the pins 13 are press-fitted into the jig 1 to maintain electrical continuity, the jig 1 is connected to an external power supply (cathode) in the same manner as in the case of conventional electroplating. The energization and electroplating may be performed in a plating solution tank containing a predetermined plating solution that is not used. That is, as shown in FIG. 8, for example, both sides of the package body 12 are gripped and fixed to the rack 31 connected to the cathode by arms 32 having a spring property.
3 may be pressed against the periphery of the jig 1 to establish electrical continuity, immersed in a plating solution, and subjected to Ni electroplating or Au electroplating.

Thus, various parts of the package 11, that is, the surface of the pin 13, and a semiconductor element mounting portion (not shown)
The bonding pad portion, the wiring pattern, and the like are plated all at once. In a subsequent step, each lead pin 13
By applying an external force in the lateral (pin diameter) direction opposite to that at the time of press-fitting, the pin is relaxed from the press-fitting hole 5 and separated from the pulling jig 1 in the pin axial direction.

The package manufactured in this manner is:
Non-plated portions are generated at two points outside the tips of the pins 13, 13.
That is, since the contact portions 6b, 6b have a knife-edge shape, the non-plated portion can be a minimum point or line. As is clear from this, the thickness t of the contact portion 6b of the opening edges 6a, 6a is determined in order to reduce the unplated area.
It is good to make it as small as possible and to make it sharp. Although there is a decrease in the biting property and an increase in the unplated area, the contact portion 6
It is also possible to make the thickness t of b smaller than the thickness T of the plate member 2 on one side only. In addition, when relaxing, it is only necessary to push back in the lateral direction, so that the plated surface is not damaged. Since the pin 13 is press-fitted (relaxed) in the lateral (pin diameter) direction, it can be press-fitted not only at the tip, but also at the intermediate portion or the root portion. Therefore, the position of the unplated portion can be selected according to the specifications of the package. Further, in the jig 1 of the present embodiment, the holes 7 are provided outside the opening edge 6a of the press-fitting hole 5 so that the opening edges 6a, 6a are bent outward when the pin 13 is press-fitted. Easy to relax. Therefore, (plastic) deformation of the opening edge 6a is prevented, which is suitable for repeated use of the jig 1, and the continuity holding property with the pin 13 is also stable and reliable. The holes 7 may be provided only outside the opening edge 6a on one side along the press-fit direction of the pins 13. In this example, since the holes 7, 7 are provided, the plating solution flows well during plating, and plating efficiency can be increased. In addition, since the removal of the plating solution due to the attachment to the jig can be reduced, the life of the solution can be extended. Note that the present invention can be embodied without providing the holes 7. However, the press-fitting and loosening of the pin are not smooth due to the absence.

In the present embodiment, the thickness T of the jig (plate-like member 2) 1
Is set to 0.3 mm, but it is preferable to make the thickness as thick as possible. As the thickness T increases, the strength (rigidity) increases, and the number of times of repeated use increases, and the holding force of the package (pin) increases. This is because the area without plating can be reduced by reducing the thickness t of the contact portion 6b of the pin. What is necessary is just to make it suitable according to the size and specification of a package. Note that FIG.
The cross-sectional shape along the line AA in FIG. 9 is the same as that shown in FIG.
> T can also be embodied. FIG. 9A is a view in which the thickness t of the contact portion 6b of the pin is reduced as a substantially quarter-arc cross section in which the upper surface angle of the opening edge is concave, and FIG.
On the contrary, the contact portion 6b of the pin is formed as a substantially 1/4 arc cross section that is convex.
Is reduced in thickness t. (C) shows the thickness of the contact portion 6b of the pin reduced through the step 6d, and (D) cuts the upper and lower corners of the opening edge into a chamfer to form a wedge. Thus, the thickness of the contact portion 6b of the pin is reduced. However, in any case, the contact portion 6b of the pin may have an arcuate cross-section (see a partially enlarged view of FIG. 3D). The openings (free insertion holes, press-fit holes) or the edges of the openings are formed by a so-called half-etching method.
What is necessary is just to form by an appropriate processing method, such as press molding and precision grinding. If the width of the press-fitting hole is too small with respect to the outer diameter of the pin, it is difficult to press-fit and relax, but the material, the thickness of the plate-like member, or the opening edge of the press-fitting hole is bent outward and deformed. An appropriate tightening (bite) allowance may be set according to whether or not it is possible.

The plating jig according to the present invention is shown in FIG.
It can also be embodied as follows. This is an improvement of only the opening in the previous example. That is, the portion at the end of the play insertion hole 4 and the hole 7 in the opening 3 of the jig 1 is cut, and when the pin 13 is pressed into the press-fit hole 5, the opening edge 6a on one side can be bent outward and deformed. It is a cantilever. In this example, since the opening edge 6a is cantilever-shaped, the pin 13 is more easily bent, so that the press-fitting and loosening of the pin 13 become smoother. The opening edges on both sides may be cantilevered, and the cut position may be selected as appropriate.

Next, still another embodiment of the jig according to the present invention will be described in detail with reference to FIG. However, this embodiment is different from the above embodiment in that the press-fit hole is tapered, but is basically common,
The description focuses on the differences, and the description is omitted as appropriate.
In the jig 41 of this example, the opening 43 has a trapezoidal shape on one side (left side in the figure), and the loose insertion hole 4 into which the pin 13 can be loosely inserted with a gap.
4, the press-fitting hole 45 continuous with the play insertion hole 44 is formed in a slit shape, and the width of the press-fitting end of the pin 13 is made smaller in a tapered shape. Note that C in FIG.
The (cross-sectional) shape of the contact portion of the pin at the opening edge 46a in the cross section taken along the line C is the same as that in FIG. 1, when the pin 13 is moved in the direction of the arrow, as shown by the two-dot chain line in FIG.
a is bent outward, and the pin 13 is press-fitted. In this example, since the press-fit hole 45 is tapered, the pin 1
3 can be press-fitted relatively easily, and wedges the opening edge 46a in combination with the cross-sectional shape (not shown) of the contact portion of the opening edge 46a. Secured. Accordingly, it is possible to effectively prevent the metal from coming off during the plating process.

In this embodiment, holes 47, 47 are formed along both sides of the opening edge 46a, and the plate-like member 42 is substantially only a rib forming the opening 43 and the hole 47. Therefore, the plating solution is very well refluxed, so that the plating film thickness can be made uniform and control can be further facilitated. In addition, the removal of the plating solution due to the attachment to the plating jig 1 can be reduced. In this example, the taper of the press-fitting hole 45 is linearly narrow, but may be a curved shape such as an arc. The taper angle may be set to an appropriate size, but is preferably in the range of 1 to 5 degrees on one side. In this example, it is also possible to make the thickness of the contact portion where the pin comes into contact smaller than the thickness of the plate member 42 on only one side. The holes 47 may be formed only on one side of the opening 43, or may not be particularly provided.

In the present invention, the opening can also be embodied by setting the planar shape of the opening as follows. As shown in FIG. 12, a portion of the opening 43 in the free insertion hole 44 and the hole 47 in the previous example is cut, and
a can also be cantilevered to be able to bend and deform outward.
Also, as shown in FIG.
May be formed in a saw-tooth shape. In this case, in addition to the above-described effects, the contact resistance at the time of press-fitting of the pin can be reduced, so that press-fitting can be performed more easily, and the area without plating can be reduced. Further, as shown in FIG. 14, a similar effect can be obtained by forming the opening edge 46a of the press-fitting hole 45 in the opening 43 in a comb shape.

The openings in the plating jig of the present invention and the play insertion holes and press-fitting holes forming the openings can be embodied as various shapes without departing from the gist of the present invention. It is not limited to one.
The number of press-fit holes may be two or more for each play insertion hole. The material of the plating jig (plate-like member) is 4
It is not limited to 2alloy products. An appropriate one may be selected from the viewpoint of conductivity, compatibility with a plating solution (chemical), and processability and strength of the opening. However, a material having a large spring property is preferable. When the plating is stripped by dipping in a plating stripping solution, a material having corrosion resistance which is not affected by the plating is selected and used. The plating jig can be used repeatedly after removing the plating, but in order to reduce the plating area, the parts (both sides) that do not require conduction are coated with an insulating material such as synthetic resin (rubber). It is good to avoid plating. By doing so, waste (amount of use) of plating can be reduced, and labor for removing plating can be reduced.

[0021]

As is clear from the above description, in the plating jig according to the present invention, the lead pin is loosely inserted into the free insertion hole of the opening and moved in the radial direction to press-fit the press-fitting hole. The thickness of the contact portion where the pin is in contact with the pin at at least one of the opening edges of the press-fit hole along the press-fit direction of the lead pin in the press-fit hole is made smaller than the thickness of the plate-shaped member. Therefore, highly reliable conduction can be easily obtained, which is effective in preventing occurrence of plating failure. Further, a portion of the pin without plating can be selected at an appropriate position. Moreover, when separating from the jig after plating, it can be easily separated without damaging the other plated surfaces by moving in reverse to the press-fitting. Therefore, it is extremely effective for improving the corrosion resistance of the package and preventing the occurrence of poor appearance, and is expected to improve the quality and reduce the manufacturing cost. In particular, the one in which the opening edge of the press-fitting hole can be bent outward and deformable is suitable for repeated use, the cost of the jig can be kept low, and the manufacturing cost of the package can be further reduced. Further, in the present invention, even if there is a variation in the tip (position) of each pin due to the inclination of the pin or the like, the pin can be easily inserted into the play insertion hole, and the inclination is positively corrected by press-fitting the press-fit hole. The effect is also expected.

[Brief description of the drawings]

FIG. 1 is a plan view and a partially enlarged view showing a first embodiment of a plating jig according to the present invention.

FIG. 2 is a partially enlarged plan view illustrating details of an opening in FIG. 1;

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a sectional view taken along line BB in FIG. 2;

FIG. 5 is a front view for explaining a state in which the package faces the plating jig of FIG. 1;

FIG. 6 is an enlarged partial cross-sectional view illustrating a process of press-fitting a lead pin in the first embodiment of the plating jig according to the present invention, wherein (A) shows the lead pin loosely inserted into a play insertion hole. FIG. 7B is an explanatory view of a state before the lead pin is pressed into the press-fitting hole by moving the slider, and FIG.

FIGS. 7A, 7B, and 7C are plan explanatory views corresponding to those in FIG. 3;

FIG. 8 shows a state in which lead pins are press-fitted into a plating jig according to the present invention, and the package is fixed to a plating rack connected to an external power supply. FIG. 3 is a plan sectional view showing a state in which conduction is established.

FIG. 9 is a cross-sectional view showing another example of the cross-sectional shape of the opening edge of the press-fitting hole.

FIG. 10 is a partially enlarged plan view illustrating an embodiment in which the opening edge of the press-fitting hole is cantilevered so as to be able to bend and deform outward.

FIG. 11 is a partially enlarged plan view illustrating still another embodiment of the opening of the plating jig according to the present invention.

FIG. 12 is a partially enlarged plan view illustrating an embodiment in which the opening edge of the press-fitting hole in FIG. 11 has a cantilever shape that can be bent and deformed outward.

FIG. 13 is a partially enlarged plan view showing another embodiment of the opening portion in FIG. 11;

FIG. 14 is a partially enlarged plan view showing still another embodiment of the opening portion.

[Explanation of symbols]

 1,41 plating jig 2,42 plate-like member 3,43 opening 4,44 loose insertion hole 5,45 press-fitting hole 6a, 46a opening edge 6b lead pin contact portion 7,47 hole 11 package 12 package body 13 lead pin t Thickness of contact part of lead pin T Thickness of plate member W Width of press-fit hole

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tomio Sato 14-18 Takatsuji-cho, Mizuho-ku Nagoya-shi Inside Japan Special Ceramics Co., Ltd. (72) Inventor Koichi Ishikawa 14-18 Takatsuji-cho Mizuho-ku Nagoya (56) References JP-A-6-302742 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 23/50 C25D 5/02 C25D 17/06

Claims (5)

(57) [Claims] 1. A plating jig used for electroplating a lead pin or the like of a package for mounting on a semiconductor, comprising a metal plate-like member, wherein the plate-like member has an arrangement of the lead pin. A plurality of corresponding openings are formed, and each of the openings is press-fitted by loosely inserting the lead pin into the play insertion hole and radially moving the lead pin through the play insertion hole. Press-fitting hole, and the thickness of the contact portion which is the opening edge of at least one side along the press-fitting direction of the lead pin in the press-fitting hole and which comes into contact with the lead pin, A plating jig characterized by being reduced in size. 2. The plating jig according to claim 1, wherein said press-fitting hole is formed in a slit shape, and has a width substantially smaller than an outer diameter of said lead pin. 3. The plating jig according to claim 1, wherein said press-fitting hole is formed in a slit shape, and a width of said press-fitting hole is formed in a tapered shape in which a portion to which said lead pin is press-fitted is small. 4. A hole provided outside the opening edge of at least one side of the press-fitting hole along the direction of press-fitting of the lead pin, the opening being capable of bending and deforming the opening edge outward. Or the plating jig according to 3. 5. The plating jig according to claim 1, wherein an opening edge of at least one side of the press-fitting hole along a press-fitting direction of the lead pin has a cantilever shape that can be bent outward and deformed. .