JP2001009398A - Ic socket cleaning method and member therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove the unnecessary solder layer or solder oxide layer bonded and deposited on the surface of the contact part of an IC socket without detaching the IC socket from a printed wiring board. SOLUTION: When the unnecessary solder layer or solder oxide layer bonded and deposited on the surface of the contact part 33 of an IC socket 31 is removed, an electrolyte gel is placed on the surface of the contact part 33 and a DC power supply is connected to the electrolyte gel so that the electrolyte gel becomes an anode and the contact part becomes a cathode to apply a current thereto and the solder layer or solder oxide layer is electrolyzed to be taken in the electrolyte gel to clean the surface of the contact part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning member for an IC socket, and more particularly to a method of removing a solder or an oxide layer thereof attached to a contact portion of an IC socket which contacts a lead of a packaged IC. The present invention relates to a cleaning method and a cleaning member.

[0002]

2. Description of the Related Art As is known, a semiconductor integrated circuit device (I
C) has a large number of leads derived from the package, and an IC socket connected to a test device (tester) for performing a final evaluation test of the IC has a large number of leads corresponding to each lead of the IC. Contact portion.

FIG. 5 schematically shows an example of an IC socket board 40 used for testing an IC device in which leads are led out from four sides of a package. The IC socket board 40 includes an IC socket 41 for mounting and testing the IC device, and an IC socket 41 on the surface.
A C socket 41 is provided via connection pins, and includes a printed wiring board 42 having a connector (not shown) connected to the test apparatus on the back surface.

The IC socket 41 is provided with a contact portion 45 for contacting each lead 44 from each side of the package 43.
And a positioning piece 46 for positioning the connection pin derived from each of the contact portions 45 and the package 43.
And the contact portion 45 is electrically connected to the connector via a wiring layer of the printed wiring board 42.

The respective leads 44 are plated with solder in consideration of the solder adhesion, and the respective contact portions 45 are plated with gold in order to maintain good contact with the respective leads 44. I have. Therefore, a large number of said I
As the evaluation test of the C device is performed, each of the leads 4
5 is provided on the surface of each of the contact portions 45 in contact with FIG.
As shown in the figure, a solder layer 47 or a solder oxide layer such as a lead oxide or tin oxide layer gradually adheres and deposits, so that the contact with each of the leads 44 is not good and an accurate evaluation test can be performed. Disappears.

Attached on the surface of each contact portion 45,
As a technique for removing and cleaning the unnecessary solder layer 47 or the solder oxide layer deposited as described above, for example, JP-A-7-2
As disclosed in Japanese Patent No. 34262, a method in which an IC socket is immersed in an acidic chemical solution, for example, hydrochloric acid, and then washed with pure water, or the unnecessary solder layer 47 or the oxide layer of solder is removed. On the other hand, there has been proposed a method of removing the abrasive by spraying it.

However, as described above, the IC
Since the socket is usually used by being attached to a printed wiring board, in the former cleaning technique, the IC socket must be removed from the printed wiring board every time cleaning is performed, and the removal operation is extremely difficult. If the IC socket attached to the printed circuit board is immersed in the chemical solution and is to be washed with pure water, the printed circuit board is also immersed in the chemical solution. The wiring section, the wiring protection section, and the like are damaged. Further, in the latter method, although it is not necessary to remove the IC socket from the printed wiring board, a masking operation is required and the gold-plated surface of the contact portion 35 is damaged.

[0008]

SUMMARY OF THE INVENTION One object of the present invention is to solve the above-mentioned drawbacks of the conventional method for cleaning an IC socket and to remove the IC socket from the printed wiring board without removing the IC socket from the printed circuit board. It is an object of the present invention to provide a method for removing an unnecessary solder layer or an oxide layer of solder, which is adhered to and deposited on a substrate.

Another object of the present invention is to provide a cleaning member for cleaning the surface of a contact portion by removing an unnecessary solder layer or a solder oxide layer adhered and deposited on the surface of a contact portion of an IC socket. It is in.

[0010]

When the surface of the contact portion is cleaned by removing an unnecessary solder layer or a solder oxide layer adhered and deposited on the surface of the contact portion of the IC socket, the surface of the contact portion is removed. An electrolyte gel is placed on the surface, and the unnecessary solder layer or solder oxide layer is removed by electrolysis to clean the surface of the contact portion.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, when an unnecessary solder layer or solder oxide layer adhered and deposited on the surface of a contact portion of an IC socket is removed, an electrolyte gel is applied to the surface of the contact portion. Placed, the electrolyte gel is a positive electrode, a direct current power supply is connected so that the contact portion is a negative electrode, electricity is supplied, and the solder layer or the oxide layer of solder is electrolyzed and taken into the electrolyte gel. The contact surface is being cleaned. An electrolyte pad impregnated with an electrolyte may be used instead of the electrolyte gel.

[0012]

FIG. 1 shows an electrolyte gel 10 mounted on the surface of a contact portion of an IC socket, for example, cut into a rectangular parallelepiped. The electrolyte gel 10 is formed as follows.

That is, potassium sulfate, magnesium sulfate,
After being formed of an electrolyte material such as sodium sulfate and sodium nitrate, the electrolyte material forms a saturated aqueous solution,
Galactomannan as a gel component in this aqueous electrolyte solution,
A gelling agent selected from agar, carrageenan, gelatin, polyvinyl alcohol and the like is added, and the mixture is heated and dissolved. Next, the heated and melted electrolyte gel material is poured into a container having a predetermined shape, cooled and molded.

FIG. 2 shows a cleaning member 20 for cleaning the surface of the contact portion of the IC socket.
The cleaning member 20 includes a platinum plate 21 serving as a positive electrode, and an electrolyte pad 22 that covers a part of the platinum plate 21 and is impregnated with the electrolyte material or the aqueous electrolyte solution.

The electrolyte pad 22 is made of non-woven fabric, foam,
It is formed of paper or the like, and is formed, for example, by impregnating a nonwoven fabric of a predetermined size with the electrolyte material or the aqueous electrolyte solution.

FIG. 3 schematically shows an IC socket board 30 similar to FIG. 5 which has been conventionally used, in which an IC device having leads led out from four sides of the package is tested. 5 shows a state in which the package of the IC device is removed and the IC socket is cleaned.

The IC socket board 30 is provided with an IC socket 31 on which the IC device is mounted for testing, and the IC socket 31 is provided on the surface via connection pins.
And a printed wiring board 32 having a connector (not shown) connected to the test apparatus on the back surface.

The IC socket 31 is provided with a contact portion 3 which comes into contact with each lead from each side of a package (not shown).
3 and a positioning piece 34 for positioning the package and the connection pin derived from each of the contact portions 33, and the contact portion 33 is electrically connected to the connector via a wiring layer of the printed wiring board 32. Connected.

As shown in FIGS. 3 and 4, when cleaning the contact portions 33, a positive electrode of a DC power source is connected to the platinum plate 21 of the cleaning member 20, and the back surface of the printed wiring board 32 is cleaned. A negative electrode of the DC power supply is connected to the contact portion 33 of the IC socket 31 via the connector provided at
The cleaning member 20 is brought into contact with a solder layer 35 or a solder oxide layer adhered and deposited on the surface of the contact portion 33, and slides in, for example, the longitudinal direction of the contact portion 33 and the arrangement direction of the contact portion 33. Then, a current is sequentially passed through the contact portion 33 to remove the solder layer 35 or a solder oxide layer such as a lead oxide or tin oxide layer deposited and deposited on the surface of the contact portion 33 by electrolysis.

By the above-described electrolysis, the solder layer 35 or the oxide layer of the solder deposited and deposited on the surface of the contact portion 33 is ionized by cathode reduction and adsorbed on the electrolyte pad 22 of the cleaning member 20. It is taken in.

When cleaning the contact portion 33, in the above-described embodiment, the cleaning member 20 is used.
Is used, but the above-mentioned electrolyte gel having a predetermined shape is arranged according to the arrangement of the contact portions 33, and a metal rod connected to the positive electrode of the DC power supply is connected to the electrolyte gel, and the electrolyte gel is electrolyzed. It is also possible to remove the solder layer 35 or the oxide layer of the solder adhered and deposited on the surface of the contact portion 33.

Further, after removing the solder layer 35 or the oxide layer of the solder from the contact portion 33, it may be treated with ion-exchanged water.

[0023]

According to the present invention, unnecessary solder layers or solder oxide layers adhered and deposited on the surface of the contact portion of the IC socket can be easily removed by the electrolyte gel or the electrolyte pad. Since the IC socket does not need to be removed from the printed wiring board, the IC socket and the printed wiring board are not damaged, and a large cleaning tank containing a chemical solution is not required.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an electrolyte gel according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a cleaning member according to an embodiment of the present invention.

FIG. 3 is a diagram schematically showing a state of cleaning a contact portion of an IC socket attached to a printed wiring board according to an embodiment of the present invention.

FIG. 4 is an enlarged plan view schematically showing a state of cleaning a contact portion of the IC socket according to the embodiment of the present invention.

FIG. 5 is a perspective view schematically showing a conventional IC socket board.

FIG. 6 is an enlarged sectional view schematically showing a contact state between a lead of an IC device and a contact portion of an IC socket.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Electrolyte gel, 20 ... Cleaning member, 21 ... Platinum plate, 22 ... Electrolyte pad, 30 ... IC socket board, 31 ... IC socket, 32 ... Printed wiring board, 33 ... Contact part, 34 ... Positioning piece, 35 ... Solder Layer or solder oxide layer

Claims (3)

[Claims] 1. An IC socket board comprising an IC socket and a printed wiring board to which the IC socket is connected, wherein a solder layer or a solder oxide layer adhered and deposited on a surface of a contact portion of the IC socket. When cleaning the surface of the contact portion by removing the contact portion, an electrolyte gel is placed on the surface of the contact portion, and the solder layer or the oxide layer of the solder is removed by electrolysis to remove the surface of the contact portion. How to clean. 2. The cleaning method according to claim 1, wherein an impregnating material impregnated with an electrolyte is used. 3. A cleaning member for cleaning a contact portion of an IC socket, said cleaning member comprising an impregnating material impregnated with said electrolyte.