KR101827541B1

KR101827541B1 - Device for test socket having crown-type surface-treated pad and method for manufacturing the same

Info

Publication number: KR101827541B1
Application number: KR1020150181178A
Authority: KR
Inventors: 박성규; 전진국
Original assignee: 주식회사 오킨스전자
Priority date: 2015-12-17
Filing date: 2015-12-17
Publication date: 2018-02-08
Also published as: KR20170072693A

Abstract

A method of manufacturing a test socket of the present invention includes the steps of: processing a connection pad in the form of a crown bump on an FPCB land; and performing a surface treatment on the crown bump to enhance the hardness of the connection pad and prevent natural oxidation . According to the structure of the present invention as described above, the contact characteristics with the conductive balls are enhanced through the roughness.

Description

Technical Field [0001] The present invention relates to a test socket having a crown-type contact pad and a surface-treated contact pad, and a method of manufacturing the test socket.

The present invention relates to a test socket having a crown shape and a surface roughness and a method of manufacturing the same, and more particularly, to a test socket for inspecting electrical characteristics before a semiconductor device manufactured through a semiconductor package manufacturing process is shipped .

In general, semiconductor devices manufactured through complicated processes are inspected for their characteristics and defects through various electrical tests.

Specifically, in the electrical inspection of semiconductor devices such as semiconductor integrated circuit devices such as a package IC and an MCM, and wafers on which integrated circuits are formed, in order to electrically connect the terminals formed on one surface of the semiconductor device to be inspected and the pads of the test device to each other , A test socket is disposed between the semiconductor device and the test apparatus.

However, the test socket is provided with a conductive connector (wire or spring, etc.) for contacting the terminals provided in the test instrument.

However, in order to carry out the test, the terminal (e.g., the conductive pad) of the test instrument must be in contact with the connection terminal (e.g., conductive ball) of the semiconductor device. At this time, since the height of the plurality of conductive balls is not constant, there are conductive pads which are in easy contact with the solder balls, but there are other conductive pads. The height variation causes contact failures.

Since the conductive pads are generally flat and formed of copper (Cu), the surface of the conductive pads is slippery, and the conductive balls are likely to disengage arbitrarily after connection. There is a problem that electrical contact characteristics are deteriorated due to the inability to pass through the native oxide film of the conductive balls due to the ductility of copper itself. It also does not prevent corrosion of copper (Cu) itself, which is continuously exposed to air.

These problems significantly deteriorate the contact characteristics between the conductive balls and the conductive pads, which is a cause of deterioration of inspection yield.

KR Patent Publication No. 10-2012-0138304

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a test socket in which a contact pad is not generated due to a flat shape and a soft nature of a conductive pad, will be.

Another object of the present invention is to provide a test socket in which a conductive pad has a surface roughness and a hardness capable of passing through a natural oxide film of a conductive ball, and a method of manufacturing the same.

According to an aspect of the present invention, there is provided a test socket comprising: an FPCB connected to an external conductive ball through a plurality of connection pads; an insulating silicone rubber bonded to an upper portion of the FPCB; A test socket comprising a conductive connector elastically supported by a silicone rubber and electrically connected to the connection pad, the conductive connector comprising a conductive wire or a conductive silicone rubber, the connection pad being provided in a crown bump type do.

According to another aspect of the present invention, there is provided a method of manufacturing a test socket, comprising the steps of: processing a connection pad in the form of a crown bump on an FPCB land; and hardening the hardness of the connection pad on the crown bump, And a surface treatment step of preventing surface roughness.

As described above, according to the configuration of the present invention, the following effects can be expected.

First, after the outer conductive ball is seated on the connection pad, there is no fear that it will be disengaged arbitrarily due to the crown shape tapering in the center direction. Particularly, the edges or corners of the crowns divided into a plurality of protrusions are rounded to facilitate seating and enhance contact properties.

Second, the metal particles are sprayed and deposited on the surface of the crown bumps to have a predetermined roughness, so that the conductive balls do not slip and are not arbitrarily removed, and can pass through the natural oxide film, thereby enhancing the contact characteristics.

Thirdly, there is an effect that silver (Au) is plated enough to cover nickel particles on the surface of copper which is easy to corrode, so that the progress of natural oxidation is suppressed and particles deposited are integrated with the connection pad.

1 is a perspective view showing a configuration of a test socket according to an embodiment of the present invention;
Fig. 2 is a perspective view showing a configuration of a test socket by round processing in Fig. 1; Fig.
3 is a sectional view taken along the line A-A 'in Fig. 1;
4 is a cross-sectional view showing a configuration in which metal particles are sprayed on the connection pad of Fig. 3; Fig.
Fig. 5 is a cross-sectional view showing a configuration in which the connection pad of Fig. 4 is metal-plated. Fig.

Brief Description of the Drawings The advantages and features of the present invention, and how to achieve them, will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. The dimensions and relative sizes of layers and regions in the figures may be exaggerated for clarity of illustration. Like reference numerals refer to like elements throughout the specification.

Embodiments described herein will be described with reference to plan views and cross-sectional views, which are ideal schematics of the present invention. Thus, the shape of the illustrations may be modified by manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention are not limited to the specific forms shown, but also include changes in the shapes that are produced according to the manufacturing process. Thus, the regions illustrated in the figures have schematic attributes, and the shapes of the regions illustrated in the figures are intended to illustrate particular types of test socket regions and are not intended to limit the scope of the invention.

Hereinafter, a preferred embodiment of a test socket including the crown-type connection pad having the above-described structure according to the present invention will be described in detail with reference to the accompanying drawings.

1 and 2, a test socket 100 according to the present invention includes an FPCB 110, a connection pad 102 and a connection pad 102. The FPCB 110 is connected to an external device through a connection pad 102, (Not shown) electrically connected to the FPCB 110, and an insulating silicone rubber 120 for elastically supporting the conductive connector on one side of the FPCB 110.

The FPCB 110 is a rigid printed circuit board (PCB) formed by printing copper (Cu) on an epoxy or phenol resin or a polyimide film having excellent ductility, A flexible printed circuit board (Flexible PCB) that forms various circuit patterns by copper (Cu), gold (Ag), and other conductive materials may be used. Here, a flexible printed circuit board is used for convenience.

The conductive connector may include an OWR-type bonding wire or an OPR-type conductive silicone rubber.

First, the conductive connector may include a conductive wire that is wire-bonded on the connection pad 102 and extends vertically. The conductive wire may protrude from the upper surface of the insulating silicone rubber 120 through the insulating silicone rubber 120. One end of the conductive wire may be connected to the connection pad 102 via the bonding joint, and the other end may be exposed to the outside.

As the conductive silicone rubber, silicone rubber, urethane rubber, epoxy rubber or other elastic rubber can be used. However, the conductive particles to be magnetically arranged may be mixed here. The conductive particles may be composed of iron, nickel, cobalt, other magnetic metal, or two or more alloys. Or a mixed type in which the above-mentioned conductive particles are plated on an insulating core. Or a compound in which a filler such as carbon (C) or the like is overfilled.

The conductive silicone rubber may be an unaligned conductive connector formed by including a conductive powder and a platinum (Pt) catalyst in a silicone rubber resin. In addition, the above-mentioned conductive powder among the unaligned conductive connectors may be a single metal of magnetic silver (Ag), iron (Fe), nickel (Ni), or cobalt (Co) .

The insulating silicone rubber 120 is not limited to silicone rubber so far as it has a predetermined elasticity. For example, polybutadiene rubber, urethane rubber, natural rubber, polyisoprene rubber, and other elastic rubbers may be used as the heat resistant polymer material having a crosslinked structure. And a base (not shown) that partially overlaps the edge of the insulating silicone rubber 120.

Here, the connection pad 102 is a portion in contact with the conductive ball of the semiconductor device to be inspected. Or may be a portion that comes into contact with the external terminal of the test apparatus for inspecting the semiconductor device.

Referring to FIG. 3, the connection pad 102 may be of the crown bump type. The crown bumps have elevations. And includes a concave portion having a first height and a convex portion having a second height higher than the first height. The convex portion surrounds the concave portion. The convex portion can be divided into a plurality. Referring again to Fig. 2, the edges (especially the corners) that are divided into a plurality can be rounded. The second height of the convex portion may be a tapered shape whose height gradually decreases toward the concave portion.

Therefore, the conductive balls can be stably mounted on the multiple projections. It can be seen that the overall contact is improved because the edges of the protruding portion and the recessed boundary region break or pierce the natural oxide film and are in contact with the conductive balls 104.

In addition, there is a possibility that the contact pad 102 and the conductive ball, which are brought into contact with each other by an iterative test process, are arbitrarily disconnected. The connection pad 102, which is arbitrarily detached, becomes a cause of contact failure. Therefore, in the embodiment of the present invention, since the height of the convex portion gradually decreases toward the concave portion, the conductive ball is supported and compressed in the center direction to prevent the conductive ball from being arbitrarily detached.

Further, the conductive balls are mounted on the connection pads 102 and surface-treated so as not to slip off. The surface of the crown-shaped connection pad 102 is surface-treated in a certain manner.

The surface treatment method primarily provides roughness. Nickel (Ni) or tungsten (W) is thermally sprayed on the connection pad 102 made of copper (Cu) to provide roughness. And secondarily provides conductivity. Silver (Ag) having a high electric conductivity is plated on nickel (Ni) or tungsten (W).

The surface-treated contact pad 102 itself has increased hardness and increased roughness, thereby remarkably improving contact properties with the conductive balls. The surface-treated connection pad 102 can avoid the natural oxide film through its surface roughness.

Since the connection pad 102 itself is formed of a metal having excellent electrical conductivity (e.g., Cu) or an alloy thereof, a natural oxide film is formed on the surface of the connection pad 102 during its formation. The natural oxide film interferes with the conduction of the conductive balls of the semiconductor device, and thus acts as a factor for greatly hindering the contact characteristics. The surface roughness breaks the natural oxide film and enhances the electrical contact property with the conductive balls. In addition, silver (Au) plating has an effect of inhibiting the progress of natural oxidation.

Hereinafter, a method of manufacturing a test socket having a crown-shaped connection pad according to the present invention will be described.

The connection pad 102, which is subjected to surface treatment through plating after the surface roughness is raised, can be post-processed by using a jig (JIG) on the completed FPCB 110 land to form a crown bump. Alternatively, the crown bump may be pre-formed and attached to the FPCB.

Surface roughening can be performed on the crown-processed bumps.

Referring to FIG. 4, a nickel (Ni) particle or a tungsten (W) particle is thermally sprayed on a copper (Cu) contact pad 102 in a single step, in particular, on a plurality of protrusions. As one of the surface treatment techniques, thermal spraying is a method in which nickel (Ni) is heated, melted or softened to make it into a particle state to collide with a crown bump. In the event of a collision, the broken particles will solidify and deposit on the crown bumps.

Referring to FIG. 5, silver (Au) is plated to a predetermined thickness on copper (Cu) in two steps. The above-described particles can be further fixed on the connection pad 102 by electroplating (or reducing plating) silver (Au). Such silver (Au) plating suppresses natural oxidation of the connection pad 102 and enhances electric conductivity.

As described above, according to the present invention, in order to prevent the conductive ball from falling off after being seated on the connection pad, the shape of the connection pad is formed into a crown shape protruding from the periphery of the center pad, tapered so as to be pressed in the center direction, It is a technical idea to construct a structure in which nickel (Ni) particles having hardness on an easy surface are sprayed to strengthen the contact and silver (Au) for preventing natural oxidation is coated on copper (Cu) . Many other modifications will be possible to those skilled in the art, within the scope of the basic technical idea of the present invention.

100: Test socket
102: connection pad
110: FPCB
120: Insulated silicone rubber

Claims

An FPCB connected to an external conductive ball through a plurality of connection pads;
An insulative silicone rubber bonded to the top of the FPCB; And
And a conductive connector elastically supported by the insulating silicone rubber and electrically connected to the connection pad,
Wherein the conductive connector comprises a conductive wire or a conductive silicone rubber,
The connection pad is provided in a crown bump type,
Wherein the crown bump has a surface roughness and thermal spraying of the second hardness metal particles through the surface treatment larger than the crown bumps of the first hardness,
The nickel (Ni) particles or the tungsten (W) particles having the second hardness are sprayed on the copper (Cu) surface having the first hardness,
The upper surface of the nickel (Ni) particle or the tungsten (W) particle is coated with silver (Au) having higher electrical conductivity than the copper (Cu), nickel (Ni), and tungsten (W) Wherein the nickel (Ni) particles or tungsten (W) particles form irregularities in the lower part to realize the surface roughness.

The method according to claim 1,
Wherein the crown bump has a height and includes a concave portion having a first height and a convex portion having a second height higher than the first height.

3. The method of claim 2,
Wherein the convex portion surrounds the concave portion, the convex portion is divided into a plurality of portions, and an edge or a corner of the divided block portion is rounded.

The method of claim 3,
And the second height of the convex portion is a tapered shape gradually becoming lower toward the concave portion.

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Processing a contact pad in the form of a crown bump on the FPCB land; And
And a surface treatment step of strengthening the hardness of the connection pad on the crown bump and preventing natural oxidation,
Depositing nickel (Ni) particles or tungsten (W) particles on the crown bumps made of copper (Cu) by thermal spraying, and
And plating silver (Au) on the copper (Cu) so as to cover at least the particles,
The upper surface of the nickel (Ni) particle or the tungsten (W) particle is coated with silver (Au) having higher electrical conductivity than the copper (Cu), nickel (Ni), and tungsten (W) Wherein the nickel (Ni) particles or the tungsten (W) particles form irregularities at the bottom to realize surface roughness.

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