WO2023003255A1

WO2023003255A1 - Contact probe

Info

Publication number: WO2023003255A1
Application number: PCT/KR2022/010176
Authority: WO
Inventors: 김학준; 김석민; 이태종; 김성호
Original assignee: 주식회사 새한마이크로텍
Priority date: 2021-07-21
Filing date: 2022-07-13
Publication date: 2023-01-26
Also published as: KR102321088B1; KR102321083B1; KR102321085B1

Abstract

The present invention relates to a contact probe and, more specifically, to a vertical-type contact probe including a plurality of layers. The present invention provides the contact probe which is used to test an electronic apparatus and comprises a tip portion, a head portion, and an elastic portion lengthily extended between the tip portion and the head portion, and at least a part of the contact probe has a multi-layered structure in which a high-conductive layer and a high-hardness layer having lower electric conductivity and higher hardness as compared with the high-conductive layer are alternately stacked.

Description

contact probe

The present invention relates to contact probes, and more particularly to vertical contact probes.

A probe card equipped with a plurality of contact probes is widely used to test the performance of flat panel displays including liquid crystal displays (LCDs) and organic light emitting diodes and semiconductor devices formed on wafers. there is.

Probe cards are largely classified into cantilever types and vertical types according to their structures. The double vertical probe card includes a first support and a second support in the form of a plate supporting both ends of the vertical contact probe. Both ends of the vertical contact probe are inserted into through holes formed in the first and second supports. When the terminal of the inspected object is pressed against the tip portion of the vertical contact probe, the vertical contact probe slides in the through hole, and the elastic portion of the vertical contact probe is bent.

In the conventional vertical probe card, a cobra pin formed by compressing a metal wire to form an elastic part is mainly used, and recently, a vertical contact probe manufactured by MEMS technology is used.

[Prior art literature]

Korean registered patent 10-0701498

Korean Registered Patent No. 10-1769355

An object of the present invention is to provide a vertical contact probe.

In order to achieve the above object, the present invention is used for testing an electronic device, and is a contact probe including a tip part, a head part, and an elastic part extending long between the tip part and the head part, at least a part of which is connected to a highly conductive layer. , It provides a contact probe characterized in that it comprises a multi-layer structure in which high hardness layers having lower electrical conductivity and greater hardness than the high conductivity layer are alternately stacked.

In addition, the contact probe further comprises an outer coating layer having higher electrical conductivity than the high-hardness layer and surrounding at least a portion of the multilayer structure.

In addition, the outer coating layer provides a contact probe, characterized in that surrounding the multi-layer structure of the head portion.

Through these configurations, contact resistance of the contact probe may be reduced or current capacity may be increased.

The high conductivity layer may be copper or a copper alloy, and the high hardness layer may be palladium or a palladium alloy. And the outer coating layer may be gold or a gold alloy.

In addition, the present invention provides a contact probe characterized in that the high hardness layer is thicker than the high conductivity layer. Through this configuration, the hardness of the contact probe can be increased.

In this case, the thickness of the high hardness layer may be 1.5 to 2 times the thickness of the high conductivity layer.

In addition, the present invention provides a contact probe characterized in that the high conductivity layer is thicker than the high hardness layer. Through this configuration, the current capacity of the contact probe can be increased.

In this case, the thickness of the high conductivity layer may be 1.5 to 2 times the thickness of the high hardness layer.

The uppermost layer and the lowermost layer of the multilayer structure are preferably the high hardness layer.

In addition, the tip part includes a multi-layered structure, and at least one of the layers constituting the multi-layered structure of the tip part is formed to protrude to provide a contact probe further comprising a skate part. Through this configuration, the scrub size by the contact probe can be reduced.

Here, the skate part may be inclined with respect to the central axis of the tip part. Through this configuration, it is possible to adjust the frictional force during scrubbing.

One side of the planar shape of the skate portion is substantially straight, and the other side facing the one side is connected to the straight portion parallel to the one side and the straight portion, and the closer the tip portion is, the further away the distance from the one side is. It may include a curved portion that is bent.

In addition, the present invention includes a coupling portion located inside the tip portion and replacing a part of the multi-layer structure at the end of the tip portion, and a skate portion extending from the coupling portion and protruding outside the tip portion, and the high hardness A contact probe comprising an insert having a higher hardness than the layer is provided. Through this configuration, the life of the skate part can be increased.

In addition, in the present invention, the elastic part includes at least two beams extending along the longitudinal direction of the elastic part, the adjacent beams are separated by a slit, and at least a portion of at least one of the beams is larger than the skate part. A contact probe characterized by having a small cross-sectional area is provided. Through this configuration, when a high current flows through the contact probe, a beam having a small cross-section is first melted. Therefore, it is possible to prevent contamination of the terminal of the element to be measured while the skate part is melted.

To this end, a cross section of at least a portion of at least one of the beams may have a groove formed on at least one surface so that the cross section is smaller than that of the skate portion.

In addition, the present invention provides a contact probe characterized in that the elastic part includes at least two beams extending along the longitudinal direction of the elastic part, and the adjacent beams are separated by a slit.

The beams may have different widths.

For example, when pressure is applied in a direction in which the tip part and the head part come closer to each other, a beam positioned in a direction in which the beams protrude may have a narrower width than a beam positioned in an opposite direction. Through these configurations, it is possible to improve a phenomenon in which a connection portion between the head portion and the beam is disconnected when pressure is applied to the contact probe.

In addition, the present invention provides a contact probe characterized in that it further comprises a stopper portion protruding from one side and the rear surface of the head portion. Through this configuration, the contact probes can be more stably supported when the contact probes are diagonally aligned.

In addition, the present invention provides a first support body having a plurality of first through holes, a second support body disposed side by side with the first support body at regular intervals and having a plurality of second through holes formed thereon, the first through holes and A probe assembly including a plurality of contact probes inserted into the second through hole is provided.

1 is a view showing a contact probe according to a first embodiment of the present invention.

FIG. 2 is a view showing a probe assembly having the contact probe shown in FIG. 1;

3 is a view showing a contact probe according to a second embodiment of the present invention.

4 is a view showing a contact probe according to a third embodiment of the present invention.

5 and 6 are views showing other examples of the skate part.

7 is a view showing another example of a tip part and a skate part.

8 is a view showing a contact probe according to a fourth embodiment of the present invention.

9 is a schematic diagram showing cross-sections of other examples of elastic parts.

10 is a view showing a contact probe according to a fifth embodiment of the present invention.

11 is a view showing a contact probe according to a sixth embodiment of the present invention.

FIG. 12 is a view showing a probe assembly having the contact probe shown in FIG. 11;

FIG. 13 shows a state in which the first through hole of the first support and the second through hole of the second support overlap when the probe assembly shown in FIG. 12 is viewed from above.

FIG. 14 is a view for explaining positions of contact probes in the first through hole and the second through hole of the contact probe of the probe assembly shown in FIG. 12;

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments introduced below are provided as examples to sufficiently convey the spirit of the present invention to those skilled in the art. Therefore, the present invention may be embodied in other forms without being limited to the embodiments described below. And in the drawings, the width, length, thickness, etc. of components may be exaggerated for convenience. Like reference numbers indicate like elements throughout the specification.

FIG. 1 is a view showing a contact probe according to a first embodiment of the present invention, and FIG. 2 is a view showing a probe assembly having the contact probe shown in FIG. 1 . 1 (a) is a front view of a contact probe, (b) is a side view, and (c) is a view showing the shape of a cross section by position.

As shown in FIG. 2 , the probe assembly 1 includes a first support 10 , a second support 20 and a plurality of contact probes 100 .

The first support 10 and the second support 20 are substantially parallel and spaced apart from each other at regular intervals. A plurality of first through holes 11 are formed in the first support 10 , and a plurality of second through holes 21 are formed in the second support 20 . In the probe assembly 1, the first through hole 11 and the corresponding second through hole 21 may be slightly offset from each other.

The first supporter 10 is disposed on the side of the space transformer (not shown) of the probe card, and the second supporter 20 is disposed on the side of the inspection target such as a semiconductor device (not shown). The first through hole 11 and the second through hole 21 are formed substantially perpendicular to the surface of each support body. The first through hole 11 and the second through hole 21 may be rectangular through holes.

As shown in (a) and (b) of FIG. 1, the contact probe 100 includes a head part 110 in contact with the circuit board of the probe card, a tip part 130 in contact with the object to be inspected, and a head part 110. It is located between and the tip part 130, and includes an elastic part 120 that is elastically deformed when pressure is applied to the tip part 130.

The tip part 130 is inserted into the second through hole 21 , and the head part 110 is inserted into the first through hole 11 .

1 and 2, the head part 110, the elastic part 120 and the tip part 130 extend in the Z-axis direction, and the elastic part 120 is slightly bent in the Y-axis direction.

The width and thickness of the tip part 130 or the elastic part 120 disposed in the second through hole 21 are smaller than the width and thickness of the second through hole 21, so that the elastic probe 100 has the second through hole. It can move in the Z-axis direction within (21). An end of the tip portion 130 is exposed to the outside of the second supporter 20 . The tip portion 130 is inclined to become thinner as it goes toward the end.

In addition, the width and thickness of the head part 110 or the elastic part 120 disposed in the first through hole 11 are smaller than those of the first through hole 11, so that the elastic probe 100 It can move in the Z direction within one through hole (11). The end 115 of the head part 110 is exposed to the outside of the first supporter 10 .

A stopper portion 115 protruding from one side of the head portion 110 is formed at an end of the head portion 110 to prevent the head portion 110 from falling out of the first through hole 11 . The lower end of the stopper part 115 is caught on the upper surface 13 of the first supporter 10 .

The head part 110 is inclined so as to become thinner as it goes toward the end.

As shown in (b) and (c) of FIG. 1, the head portion 110, the elastic portion 120, and the tip portion 130 include a multilayer structure including a plurality of layers made of different conductive materials. .

The multilayer structure is a structure in which highly

conductive layers

110b, 120b, and 130b and

high hardness layers

110a, 120a, and 130a are alternately laminated. In this embodiment, the head portion 110, the elastic portion 120, and the tip portion 130 all include a multi-layer structure. The uppermost and lowermost layers of the multilayer structure are preferably

high hardness layers

110a, 120a, and 130a.

The high-

hardness layers

110a, 120a, and 130a are made of materials having lower electrical conductivity and higher hardness than the high-

conductivity layers

110b, 120b, and 130b. For example, the

high conductivity layers

110b, 120b, and 130b may be made of copper or a copper alloy, and the

high hardness layers

110a, 120a, and 130a may be made of palladium or a palladium alloy.

To improve the hardness of the contact probe, the high-

hardness layers

110a, 120a, and 130a may be thicker than the high-

conductivity layers

110b, 120b, and 130b. More specifically, the thickness of the high-

hardness layers

110a, 120a, and 130a may be 1.5 to 2 times the thickness of the high-

conductivity layers

110b, 120b, and 130b.

As shown in (c) of FIG. 1, the head portion 110, the tip portion 130, and the elastic portion 120 have a rectangular cross section.

As shown in (b) and (c) of FIG. 1 , the contact probe 100 of this embodiment further includes a coating layer 140 surrounding at least a portion of the multilayer structure.

The coating layer 140 has higher electrical conductivity than the

high hardness layers

110a, 120a, and 130a. For example, coating layer 140 may be gold or a gold alloy. The coating layer 140 covers the entire slope of the multilayer structure. In this embodiment, the coating layer 140 surrounds at least a portion of the multilayer structure of the head portion 110 . In this embodiment, the coating layer 140 serves to lower contact resistance.

* This embodiment is different from the embodiment shown in FIG. 1 in that the coating layer 250 is formed over the entire contact probe 200. In this embodiment, since the coating layer 250, which has higher electrical conductivity than the high-

hardness layers

210a, 220a, and 230a, covers the entire contact probe 200, current carrying capacity (CCC) is improved. In addition, since the side surfaces of the multi-layer structure are covered with the coating layer 250, gaps that may occur between layers are not exposed to the outside, thereby preventing oxidation of the multi-layer structure.

In addition, in this embodiment, to improve the current capacity of the contact probe 200, the

high conductivity layers

210b, 220b, and 230b may be thicker than the

high hardness layers

210a, 220a, and 230a. More specifically, the thickness of the

high conductivity layers

210b, 220b, and 230b may be 1.5 to 2 times the thickness of the

high hardness layers

210a, 220a, and 230a.

The embodiment shown in FIG. 4 is different from the embodiment shown in FIG. 1 in that the elastic part 320 has a dual beam structure.

The elastic part 320 of this embodiment includes a pair of

beams

321 and 323 divided by a slit 325 .

In addition, at least one of the layers constituting the multi-layered structure of the tip portion 330 is formed by protruding long, and the skate portion 335 having a thickness smaller than that of the tip portion 330 is further provided, similar to the embodiment shown in FIG. 1. There is a difference. The end of the skate part 335 contacts the terminal of the device to be measured. Since the thickness of the skate part 335 is thinner than that of the tip part 330, the application of the skate part 335 has the advantage of reducing the size of the scrub. In addition, if the length of the skate portion 335 is increased, there is an advantage in that, when there is a protruding structure, such as a microbump, around the terminal of the device to be measured, it is possible to avoid the protruding structure and contact the terminal.

In this embodiment, the skate portion 335 includes two high-hardness layers 335a and one high-conductivity layer 335b.

5 and 6 are views showing other examples of the skate part. The skate portion of FIG. 4 may be replaced with the skate portions of FIGS. 5 and 6 .

These examples are different from the embodiment shown in FIG. 3 in that the

skate parts

336 and 337 are inclined with respect to the central axis of the tip part 330 . It is tilted to adjust the frictional force during scrubbing.

In the example shown in FIG. 5 , one side 3361 extending from the tip portion 330, based on the planar shape of the skate portion 336 viewed from the front, generally forms an angle with the central axis of the tip portion. It is a straight line formed by The other side 3362 facing the one side 3361 includes a curved portion 3332a and a straight portion 3332b connected to each other. The curved portion 3332a extends from the tip portion 330 and is bent so that the distance from the one side 3361 increases as it gets closer to the tip portion 330. The straight portion 3332b is parallel to one side 3361 and connected to the curved portion 3332a.

The example shown in FIG. 6 is different from the embodiment shown in FIG. 5 in that the skate portion 337 is made of one high-hardness layer 337a.

7 is a view showing another example of a tip part and a skate part.

The embodiment shown in FIG. 7 includes an insert portion 350 . The insert portion 350 is generally in the form of a rectangular plate. The insert portion 350 includes a coupling portion 354 positioned inside the tip portion 340 and a skate portion 355 extending from the coupling portion 354 and protruding outward from the tip portion 340 .

The coupling portion 354 replaces a portion of the multilayer structure at the end of the tip portion 340 . In this example, the coupling part 354 replaces two high-hardness layers 340a and one high-conductivity layer 340b in the multilayer structure constituting the tip part 340 .

The insert portion 350 may have higher hardness than the high hardness layer 340a. For example, palladium may be used as the high-hardness layer 340a and rhodium may be used as the insert portion 340 . This embodiment has the advantage of improving the life shortening due to mechanical wear of the skate portion 355 .

The embodiment shown in FIG. 8 is different from the embodiment shown in FIG. 4 in that

grooves

427 and 428 are formed in some sections of the pair of

beams

421 and 423 of the elastic part 420. It is preferable that at least one of the cross-sectional areas (A _B1 , A _B2 ) of the beams in the section in which the

grooves

427 and 428 are formed is smaller than the cross-sectional area (A _S ) of the skate portion 435 . This is to minimize contamination of the terminal of the device to be measured as the contact probe 400 melts when a high current momentarily flows through the contact probe 400.

When a high current instantaneously flows through the contact probe 400, the part with the smallest cross-sectional area in the contact probe 400 is melted by Joule's heat. At least one of the cross-sectional areas (A _B1 , A _B2 ) of the

beams

421 and 423 of is smaller than the cross-sectional area (A _S ) of the skate portion 435 contacting the terminal of the device to be measured. Then, since the

beam

421 or 423 far from the terminal melts first compared to the skate part 435 when a high current flows, contaminating the terminal of the device to be measured while the skate part 435 melts can be prevented.

Although the contact probe 400 is not shown as having a multilayer structure in FIG. 8 , the contact probe 400 according to the fourth embodiment may also have a multilayer structure.

As shown in (a) of FIG. 9,

grooves

427 and 428 may be formed on the inner surface of the

beams

421 and 423, and as shown in (b), formed on the surface facing the same direction. It may be done, and as shown in (c) and (d), it may be formed on only one beam 421.

The embodiment shown in FIG. 10 is different from the embodiment shown in FIG. 4 in that the left beam 521 and the right beam 523 have different widths.

The

beams

521 and 523 are bent when pressure is applied in the direction in which the tip part 530 and the head part 510 come closer in order to measure electrical characteristics. Beam 521 located in the protruding direction (-y direction) The width may be narrower than that of the beam 523 located on the opposite side. This is to improve the phenomenon in which the beam 523 located on the opposite side of the head portion 510 and the beam 521 is disconnected.

11 is a view showing a contact probe according to a sixth embodiment of the present invention, FIG. 12 is a view showing a probe assembly having the contact probe shown in FIG. 11, and FIG. 13 is a view showing the probe assembly shown in FIG. It shows a state in which the first through hole of the first support and the second through hole of the second support overlap when viewed from above.

As best shown in FIG. 11(c), the embodiment shown in FIG. 11 is the embodiment shown in FIG. 1 in that the

stoppers

615 and 617 are formed not only on the side surface of the head part 610 but also on the rear surface. Yes, there is a difference.

As shown in FIG. 13 , when the probe assembly 2 is viewed from above, the first through hole 11 of the first support 10 and the second through hole 21 of the second support 20 are rectangular. , and the first through hole 11 and the second through hole 21 are offset by a distance L in the diagonal direction of the first through hole (or the second through hole). After inserting the contact probe 600 into the first through hole 11 and the second through hole 21 in a state in which the first through hole 11 and the second through hole 21 are aligned, the first support ( 10) can be achieved by a method of relatively moving the second supporter 20 by a distance L in a diagonal direction.

As shown in FIG. 14 , when the first through hole 11 and the second through hole 21 are offset in the diagonal direction in this way, the head portion 610 of the contact probe 600 is the first through hole 11 is adhered to one corner of the side. The tip 630 is in close contact with one corner of the first through hole 11 and the opposite corner of the second through hole 21 disposed diagonally. At this time, the lower surfaces of the

stoppers

615 and 617 are in close contact with the upper surface 13 of the first support 10 . In this embodiment, since the

stoppers

615 and 617 are formed on the rear surface as well as the side surface of the head part 610, the contact probe 600 is slightly moved so that the head part 610 of the contact probe 600 is not biased to one side. more stable support.

Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific embodiments described above, and is common in the art to which the present invention pertains without departing from the gist of the present invention claimed in the claims. Of course, various modifications and implementations are possible by those with knowledge of, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.

For example, although the elastic part is shown as having a pair of beams in FIG. 4 , it may include three or more beams.

In addition, the tip portion or skate portion of each embodiment may be replaced with a tip portion or skate portion of another embodiment.

[Description of code]

1, 2: probe assembly

10: first support

20: second support

100, 200, 300, 400, 500, 600: contact probe

110, 210, 310, 410, 510, 610: head

120, 220, 320, 420, 520, 620: elastic part

130, 230, 330, 430, 530, 630: tip part

Claims

A contact probe used for testing an electronic device and including a tip portion, a head portion, and an elastic portion extending between the tip portion and the head portion,

At least some of them include a multi-layer structure in which a high-conductivity layer and a high-hardness layer having lower electrical conductivity and greater hardness than the high-conductivity layer are alternately stacked,

A coupling portion located inside the tip portion and replacing a part of the multi-layered structure at an end of the tip portion, and a skate portion extending from the coupling portion and protruding outward from the tip portion, and having a hardness greater than that of the high-hardness layer. A contact probe comprising a taller insert.
According to claim 1,

The contact probe further comprises an outer coating layer having higher electrical conductivity than the high-hardness layer and surrounding at least a portion of the multilayer structure.
According to claim 2,

The contact probe, characterized in that the outer coating layer surrounds the multi-layer structure of the head portion.
According to claim 1,

The contact probe according to claim 1, wherein the high conductivity layer is copper or a copper alloy, and the high hardness layer is palladium or a palladium alloy.
According to claim 2,

The contact probe, characterized in that the outer coating layer is gold or gold alloy.
According to claim 1,

The contact probe, characterized in that the high hardness layer is thicker than the high conductivity layer.
According to claim 6,

The contact probe, characterized in that the thickness of the high hardness layer is 1.5 to 2 times the thickness of the high conductivity layer.
According to claim 1,

The contact probe, characterized in that the high conductivity layer is thicker than the high hardness layer.
According to claim 8,

The contact probe, characterized in that the thickness of the high conductivity layer is 1.5 to 2 times the thickness of the high hardness layer.
According to claim 1,

The contact probe, characterized in that the uppermost layer and the lowermost layer of the multi-layer structure are the high hardness layer.
According to claim 1,

The contact probe, characterized in that the skate portion is inclined with respect to the central axis of the tip portion.
According to claim 11,

One side of the planar shape of the skate portion is straight, and the other side facing the one side is connected to the straight portion parallel to the one side and the straight portion, and is bent so that the distance from the one side increases as it gets closer to the tip portion. A contact probe, characterized in that it comprises a curved portion.
According to claim 1,

The elastic part includes at least two beams extending along the longitudinal direction of the elastic part, and the adjacent beams are separated by a slit,

At least a portion of at least one of the beams has a smaller cross-sectional area than the skate portion.
According to claim 13,

A contact probe, characterized in that a groove is formed on at least one surface of at least a portion of at least one of the beams so that the cross section is smaller than that of the skate portion.
According to claim 1,

The contact probe of claim 1 , wherein the elastic part includes at least two beams extending along the longitudinal direction of the elastic part, and the adjacent beams are separated by a slit.
According to claim 15,

The contact probe, characterized in that the beams have different widths.
According to claim 16,

The beams are contact probes, characterized in that when pressure is applied in a direction in which the tip portion and the head portion come closer, a beam positioned in a direction in which the beams protrude is wider than a beam positioned in an opposite direction.
According to claim 1,

The contact probe further comprises a stopper protruding from one side surface and a rear surface of the head part.
A first support body having a plurality of first through holes;

A second support body disposed side by side with the first support body at regular intervals and having a plurality of second through holes;

It includes a plurality of contact probes inserted into the first through hole and the second through hole,

The contact probe is a probe assembly according to any one of claims 1 to 18.