JP3578708B2 - IC socket - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a measuring device for performing an electrical characteristic test of a semiconductor package, wherein an IC for electrically connecting leads of the IC package to a measuring circuit of the measuring device by loading a semiconductor integrated circuit (IC) package. The present invention relates to a socket, particularly to an IC socket of a flat pack type IC package.
[0002]
[Prior art]
FIG. 7 is a partial cross-sectional view of an IC socket of a flat pack type IC package showing an example of the related art. As shown in FIG. 7, the IC socket is mounted on the socket base 200, is mounted on the socket base 200, is bent laterally in a U-shape protruding from the surface of the socket base 200, and is further bent vertically upward to form a tip portion. A socket pin 201 provided with a contact portion for making contact with a lead 203 of a flat-pack type device 205, and the device 205 is set on a device mounting portion of the socket base 200, and then the device 205 is pressed to release the socket pin 201. And a socket lid 202 for bringing the lead 203 into contact with the socket. This type of IC socket is mounted on a test board (not shown) so that the socket pins 201 are inserted and used. This IC socket is used for an IC package used in a normal frequency range.
[0003]
As an IC socket for a high-frequency IC package, Japanese Patent Application Laid-Open No. 8-236237 discloses a technique using an S-shaped contact in order to reduce a contact line length. FIG. 8 is a perspective view of an essential part of an IC socket using the S-shaped contact. As shown in FIG. 8, this IC socket has a socket base 40 on which a device 20 (IC package) having leads 30 formed thereon is mounted, and the socket base 40 main body 5a is mounted on a test board 51a provided with electrode pads. It has a structure to be mounted. In particular, the socket base 40 has an S-shaped contact 70 and two elastomers which are respectively fixed to the upper and lower sides to hold the S-shaped contact 70, and the S-shaped contact 70 is attached to the socket base 40. It is inserted into the processed slot groove 80.
[0004]
The socket base 40 is fixed to the test board 51a with screws or the like. At this time, the S-shaped contact 70 protrudes about 0.2 mm from the bottom surface of the socket base 40, and deforms the lower elastomer when fixed to the test board 51a. The S-shaped contact 70 is held in contact with the electrode pad of the test board 51a by the load given by this deformation. When the lead 30 of the device 20 is placed on the upper surface of the S-shaped contact 70 and an appropriate contact pressure is applied, the S-shaped contact 70 rotates while deforming the elastomer. Thus, the S-shaped contact 70 is interconnected while rubbing the contact surfaces of the leads 30 of the device 20 and the contact surfaces of the electrode pads of the test board 51a.
[0005]
[Problems to be solved by the invention]
In the IC socket of FIG. 7 described above, although the lead 203 of the device 205 and the tip of the socket pin 201 can surely come into contact with each other, a slip occurs between the contact of the tip of the socket pin 201 and the lead 203, and The solder plating surface is easily damaged, and the solder is easily transferred to the tip of the socket pin 201. As the number of times the IC socket is used increases, the solder transferred to the tip of the socket pin 201 is oxidized, increasing the surface resistance of the tip of the socket pin 201 and causing poor contact between the IC socket and the lead 203 of the device. Was causing it.
[0006]
Also in the IC socket of FIG. 8, the S-shaped contact 70 slides on the surface of the lead 30 of the device 20 or performs a rotating operation. Oxidation of the transferred and transferred solder similarly to the IC socket of FIG. 7 causes a problem that a contact failure between the S-shaped contact 70 and the lead 30 is increased due to an increase in contact resistance therebetween.
[0007]
Accordingly, an object of the present invention is to solve the above-mentioned drawbacks of the conventional IC socket (contact device) and to provide an inexpensive IC socket with an improved life which can suppress the occurrence of scratches on the leads of a flat pack type IC package. Is to do.
[0008]
[Means for Solving the Problems]
The IC socket according to the first configuration of the present invention is mounted on a socket base and a through hole provided in the socket base at a position corresponding to a tip end of a lead of a flat pack type semiconductor integrated circuit package to be inspected. A socket pin having a test board insertion portion protruding from the back surface of the socket base and having a flat surface exposed at the other end to the surface of the socket base; and a through-hole of the socket base mounted on the socket base. The exposed surface of the socket pin is fixed from above by the groove, and the socket base having the mounting portion of the package on the surface is in contact with the socket pin in the groove. installed was able to freely rotate as the O-shaped ring-like contact which deflection caused by pressure from above, the socket And a socket lid having a lead holding portion for pressing the tip of the lead of the package on the lower surface and contacting the contact with the lead of the package on the lower surface. .
[0009]
An IC socket having a second configuration according to the present invention includes a socket base having a groove penetrating to a position corresponding to a tip of a lead of a flat pack type semiconductor integrated circuit package to be inspected and a mounting portion of the package on a surface thereof; A test board disposed on the back surface of the base and having a pad at a position corresponding to the groove; and a test board disposed in the groove so as to contact the pad, which can freely rotate, and bends when pressed from above. An O-shaped ring-shaped contact, and a socket lid that is placed on the socket base and has a lead pressing portion that presses the leading end of the lead of the package on the lower surface and contacts the contact with the contact. It is characterized by having.
[0010]
In the first and second configurations of the present invention described above, a cutout for cutting the contact in the width direction may be provided in a part of the O-shaped contact . Further, the inside of the ring of the O-shaped contact can be filled with a conductive resin to reduce the electric resistance of the contact.
[0011]
The present invention is characterized in that an O-shaped ring-shaped contact is provided in an IC socket as in the first and second configurations. The contact is not fixed in the IC socket by welding or soldering, but is merely arranged to contact the socket pin (first configuration) or the test board pad (second configuration). When a lead of a flat pack type semiconductor integrated circuit package (hereinafter, simply referred to as a device) is pressed by the contact and comes into contact with the lead, the lead rotates by a lateral force applied to the lead and slides with the lead. Can be reduced. As a result, scraping of the solder plating of the device leads and transfer to the contact surface can be prevented, and occurrence of a contact failure accident due to the transferred solder in the conventional IC socket can be prevented.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
[0013]
FIG. 1 is a sectional view of a main part of an IC socket according to a first embodiment of the present invention, and FIG. 2 is a plan view of the IC socket of FIG. FIG. 1 is a sectional view taken along line AA ′ of FIG. As shown in FIG. 1, this IC socket has a socket base 1 formed of an insulating material and a through hole 3a provided in the socket base 1 at a position corresponding to the tip of the lead 30 of the device 20 to be mounted. One end thereof protrudes from the back surface of the socket base, the other end has a flat surface, and a conductive socket pin 3 mounted so that the flat surface is exposed on the surface of the socket base 1; Having a groove 6 at a position corresponding to the through hole 3a of the socket base 1, fixing the tip of the socket pin 3 from above at the groove 6, and having a mounting portion for the device 20 on the surface. And a O-shaped ring-shaped conductive contact 10 installed in the groove 6 so as to come into contact with the socket pin 3, and mounted on the socket base 2, and socket And a socket cover 5 which is molded of dielectric material having a lead holding portion 5a of the projecting pressing the tip of the lead 30 of the device 20 to be placed on 2.
[0014]
As shown in FIG. 1, in the IC socket of the present embodiment, a ring-shaped contact 10 is placed in a groove 6 of a socket base 2, and a lead 30 of a device 20 and a socket pin 3 are inserted through the contact 10. It has a great feature in that it is electrically contacted. The contact 10 is not joined to the socket pin 3 by soldering, welding, or the like, but is simply placed on a flat surface at the tip of the socket pin 3. Therefore, the contact 10 can rotate freely. For this reason, the device 20 is incorporated into an IC socket, and the lead 30 is pressed by the lead holding portion 5a, so that there is no sliding when the contact 10 contacts the lead 30. Transfer of solder plating can be prevented. Therefore, it is possible to prevent the occurrence of contact failure due to solder plating transfer as in the conventional IC socket. Note that the clearance between the contact 10 and the side wall of the groove 6 needs to be 200 μm or more in order to rotate the contact 10.
[0015]
The ring diameter of the contact 10 can be freely determined, but is usually about 1 to 2 mm. The ring width of the contact 10 is about 0.1 to 0.3 mm. As a material of the contact 10, a Be—Cu alloy is used, and Ni is plated with a thickness of 1 to 5 μm and Au is plated with a thickness of 0.2 to 1 μm. The spring constant of the contact 10 is set to about 0.03 to 0.05 kgf / cm so that sufficient deflection is generated by pressing from above. FIG. 5A is a perspective view of the contact 10 of FIG.
[0016]
Next, an IC socket according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a sectional view of a main part of an IC socket according to a second embodiment of the present invention. In the present embodiment, a contact 10b having a cutout for cutting the ring in the width direction is used in a part of the ring instead of the contact 10 of FIG. As a material of the contact 10a, a Be-Cu alloy similar to the contact 10 of FIG. 1 can be used, but a material having a spring constant of about 0.1 kgf / cm is used. The surface of the contact 10a is also plated with Ni / Au in the same manner as the contact 10 of FIG. Also in the present embodiment, the contact 10a is not joined to the socket pin 3 by soldering, welding, or the like, but is simply placed on the flat surface at the tip of the socket pin 3, as in the first embodiment. Is placed. Therefore, since the contact 10a can rotate freely, the device 20 is incorporated into the IC socket, and the lead 30 is pressed by the lead holding portion 5a, and there is no sliding when the contact 10a and the lead 30 come into contact. The scraping of the solder plating of the lead 30 and the transfer of the solder plating to the contact 10a can be prevented, and the occurrence of poor contact between the lead 30 of the device 20 and the contact 10a due to an increase in the number of times the IC socket is used can be prevented. FIG. 5B is a perspective view of the contact 10a of FIG.
[0017]
Next, an IC socket according to a third embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a sectional view of a main part of an IC socket according to a third embodiment of the present invention. In the present embodiment, a contact 10b in which a rubber elastic conductive resin 100 is filled inside the ring is used instead of the contact 10 of FIG. In the present contact 10b, the electrical resistance of the contact can be lower than that of the contact 10 in FIG. As the conductive resin 100, a material in which metal particles such as Cu, Ag, and Au are filled in a polyurethane resin can be used. The contact 10b is prepared by applying Ni plating and Au plating to a Be—Cu alloy ring, and then filling the inside of the ring with a conductive resin 100. Alternatively, it can be prepared by sequentially forming electroless nickel plating and electroless gold plating, and then cutting to a predetermined ring width (for example, 0.3 mm). In the case of the latter preparation method, it is desirable to add Pd metal particles to the conductive resin 100 in addition to the above-mentioned Cu, Ag or Au metal particles in order to promote deposition of electroless plating. The same effects as those of the IC socket according to the first embodiment of the present invention can be obtained with the IC socket according to the present embodiment. FIG. 5C is a perspective view of the contact 10b of FIG.
[0018]
Next, an IC socket according to a fourth embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a sectional view of a main part of an IC socket according to a fourth embodiment of the present invention.
[0019]
The IC sockets of the first to third embodiments are used by mounting the socket pins 3 protruding from the socket base 1 on a test board (not shown). In the socket, the socket base 60 also serving as a socket base is directly mounted on the test board, and the contact 10 is brought into direct contact with the pad 51 of the test board 50. In the IC socket of the present embodiment, in addition to the same effects as those of the IC socket of the first embodiment, the electric resistance between the lead 30 and the pad 51 of the test board 50 can be reduced. An IC socket suitable for a device can be provided. In FIG. 6, the same contact 10 as in FIG. 1 is used, but it goes without saying that the same contact as in FIGS. 5B and 5C can also be used.
[0020]
【The invention's effect】
As described above, the IC socket of the present invention has the following advantages.
(1) The contact that comes into contact with the lead of the flat pack type IC package can be rotated, the scraping of the solder plating on the lead can be suppressed, and the solder transfer of the lead to the contact can be prevented.
(2) As a result, an increase in the contact resistance between the device lead and the contact can be prevented, and the life of the IC socket can be improved.
[Brief description of the drawings]
FIG. 1 is a sectional view of a main part of an IC socket according to a first embodiment of the present invention.
FIG. 2 is a plan view of the IC socket of FIG. 1;
FIG. 3 is a sectional view of a main part of an IC socket according to a second embodiment of the present invention.
FIG. 4 is a sectional view of a main part of an IC socket according to a third embodiment of the present invention.
FIG. 5 is a perspective view of a contact used in the IC socket according to the first to third embodiments of the present invention.
FIG. 6 is a sectional view of a main part of an IC socket according to a fourth embodiment of the present invention.
FIG. 7 is a sectional view of a main part of a conventional IC socket.
FIG. 8 is a perspective view of a main part of another conventional IC socket.
[Explanation of symbols]
1, 40, 60, 200 Socket base 2 Socket base 3, 201 Socket pin 3a Through hole 5, 202 Socket lid 5a Lead presser 6 Groove 10, 10a, 10b Contact 20, 205 Device 30, 203 Lead 50, 51a Test Board 51 Pad 70 S-shaped contact 80 Slot groove 100 Conductive resin

Claims (10)

A test board insertion part which is mounted on a socket base and a through hole provided in the socket base at a position corresponding to a tip end of a lead of a flat pack type semiconductor integrated circuit package to be inspected, and one end of which protrudes from the back surface of the socket base. Having a socket pin having the other end having a flat surface exposed on the surface of the socket base, and a groove mounted on the socket base and penetrating at a position corresponding to the through hole of the socket base, The exposed surface of the socket pin is fixed from above in the groove, and a socket base having a mounting portion of the package on a surface thereof, and freely rotatable installed in the groove so as to contact the socket pin can be provided. , and O-shaped ring-like contact which deflection caused by pressing from above, is mounted on said socket board, said the lower surface package IC socket, characterized in that a socket lid presses the tip portion of the lead of di-, having the lead holding portion for contacting the leads of the package to the contactor. A socket base having a groove penetrating to a position corresponding to the tip of the lead of the flat pack type semiconductor integrated circuit package to be inspected and a mounting portion of the package on the surface, and a socket base disposed on the back surface of the socket base and corresponding to the groove A test board having a pad at a position, an O-shaped ring-shaped contact that is disposed in the groove so as to be in contact with the pad, is freely rotatable, and is bent by being pressed from above, and the socket base. An IC socket, comprising: a socket lid mounted on an upper surface thereof and having a lead pressing portion for pressing a leading end portion of the lead of the package on a lower surface thereof and contacting the contact with the contact. 3. The IC socket according to claim 1 , wherein a notch for cutting the contact in a width direction is provided in a part of the contact. 3. The IC socket according to claim 1 , wherein a conductive resin is filled inside the ring of the contact . The IC socket according to any one of claims 1 to 4 , wherein the contact is based on a Be-Cu alloy, and a surface thereof is sequentially plated with Ni and Au. 5. The IC socket according to claim 4 , wherein the conductive resin filled in the inside of the ring of the contact contains a polyurethane resin and Cu, Ag or Au metal particles. The contact is characterized by being prepared by sequentially applying electroless copper plating, electroless nickel plating, and electroless gold plating to a cylindrical conductive resin molded body, and then cutting to a predetermined ring width. The IC socket according to claim 4 or 6, wherein The IC socket according to claim 7, wherein the conductive resin molded body contains a polyurethane resin and Cu, Ag, or Au metal particles. 3. The IC socket according to claim 1, wherein the contact has a spring constant of 0.03 to 0.05 kgf / cm. 4. The IC socket according to claim 3, wherein the contact has a spring constant of about 0.1 kgf / cm.

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