WO2018093109A2

WO2018093109A2 - Probe for testing device

Info

Publication number: WO2018093109A2
Application number: PCT/KR2017/012845
Authority: WO
Inventors: Jae-Hwan Jeong
Original assignee: Leeno Industrial Inc.
Priority date: 2016-11-21
Filing date: 2017-11-15
Publication date: 2018-05-24
Also published as: WO2018093109A3

Abstract

Disclosed is a probe for testing an electric characteristic of an object to be tested. The probe includes a core with conductive properties and shaped like a bar; and an elastic plating layer made of a material having higher elasticity than the core and plated on an outer surface of the core. The probe according to the present disclosure is not only excellent in contact with the object to be tested and durability but also has low resistance, and makes it easy to manufacture a probe supporter for supporting the probe.

Description

PROBE FOR TESTING DEVICE

The present disclosure relates to a probe for a testing device, which tests electric characteristics of an object to be tested, such as a semiconductor.

As a testing device for testing an electric characteristic or adequacy of a semiconductor wafer and the like object to be tested, there has been used a probe card which includes a plurality of probes for electrically connecting a tested contact point (e.g. a terminal, a bump) of the object to be tested and a testing contact point (e.g. a pad) of a testing circuit, and a probe supporter for supporting the probes.

With development of technologies, the size of the semiconductor wafer has become larger, and the degree of circuit integration has been gradually raised. Accordingly, the number of pads to be formed on one sheet of wafer is also increased, and thus a distance between the semiconductor pads has to become narrower. The narrower such a pad pitches is, the more the probes of the probe card have to be densely arranged.

In general, the probe card employs a cantilever type probe, a vertical type probe, a microelectromechanical systems (MEMS) type probe, etc. The cantilever type has lower manufacturing costs than the MEMS or vertical type, but has disadvantages that all processes are one by one modified and performed by a person. Therefore, if the cantilever type probe card needs to be fixed or repaired, it is a hassle since a person has to rearrange pins one by one.

On the other hand, the MEMS or vertical type probe costs high but has very high precision since the probes are connected with assistance from a precision machine.

A conventional MEMS type probe card employs a probe 10 having a quadrangular cross-section where a plurality of elastic layers 15 and conductive layers 14 are horizontally laminated as shown in FIG. 1. However, the conventional MEMS type probe has poor contact and increases in contact resistance since the ends of the plurality of laminated probes are in contact with an object to be tested. Further, the conventional MEMS type probe has a disadvantage of having a short lifespan because of fatigue failure between an intermediate elastic transformable portion and a fixed end to be in contact with a substrate pad as the test is repeated. In particular, a structure for supporting the conventional MEMS type probe having the quadrangular cross-section needs to have quadrangular through holes at very fine pitches. However, it is difficult to form such a very small quadrangular through hole, and thus manufacturing costs increase.

The present disclosure is conceived to solve the foregoing problems, and provides a probe for a testing device, which has good contact with an object to be tested, is excellent in durability, decreases in resistance, and makes it easy to manufacture a probe supporter.

In accordance with an embodiment of the present disclosure, there is provided a MEMS probe for a testing device. The probe for the testing device includes a core with conductive properties and shaped like a bar, and an elastic plating layer made of a material having higher elasticity than the core and plated on the core. Such a probe is excellent in conductivity based on a highly conductive core, contact with an object to be tested, and durability.

The probe may further may include a ductile plating layer made of a material having lower elasticity than the elastic plating layer and plated to the core.

The probe may further include at least one additional laminate portion to be plated and laminated to the elastic plating layer or the ductile plating layer, thereby having desired resistance and elasticity.

The probe may further include an insulating layer configured to surround an outer surface of the additional laminate portion, thereby preventing a short with an adjacent probe.

The core may include at least one end tip configured to be in contact with the object to be tested, thereby improving the contact.

The core may have one of a circular cross-section, an elliptical cross-section, a polygonal cross-section, and a star-shaped cross-section.

The elastic plating layer may be plated with a Pd (palladium) alloy or a Ni (nickel ) alloy; the ductile plating layer may be plated with at least one of Au (gold), Pt (platinum), Ag (gold), Cu (copper), and Al (aluminum); and the core may be made of Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

The core may include a first contact portion configured to contact a first contact point, a second contact portion configured to contact a second contact point, and an elastic transformable portion configured to be transformed by press in a lengthwise direction during a test, and the elastic plating layer may include a first elastic plating layer plated on the first contact portion, a second elastic plating layer plated on the second contact portion, and a third elastic plating layer plated on the elastic transformable portion.

The ductile plating layer may include a first ductile plating layer plated to the first contact portion, a second ductile plating layer plated to the second contact portion, and a third ductile plating layer plated to the elastic transformable portion.

The first and second elastic plating layers, the first and second ductile plating layers and first and second additional laminate portions, which are plated on the first contact portion and the second contact portion, may have lower elasticity and higher conductivity than a third elastic plating layer, a third ductile plating layer and a third additional laminate portion, which are plated to an elastic transformable portion.

The elastic transformable portion may have a smaller cross-section than the first contact portion or the second contact portion.

The core may include a first contact portion configured to contact a first contact point, a second contact portion configured to contact a second contact point, and an elastic transformable portion configured to be transformed by press in a lengthwise direction during a test, and the elastic plating layer may be plated on only the elastic transformable portion.

The core may include a first contact portion configured to contact a first contact point, a second contact portion configured to contact a second contact point, and an elastic transformable portion configured to be transformed by press in a lengthwise direction during a test, and the elastic transformable portion may include at least one slot extending in the lengthwise direction.

The elastic plating layer may be plated on a plurality of bridges configured to form the slot.

A probe for a testing device according to the present invention has good contact with an object to be tested, is excellent in durability, decreases in resistance, and makes it easy to manufacture a probe supporter.

FIG. 1 is a perspective view of showing a structure of a conventional MEMS probe;

FIG. 2 is a testing device with a probe according to a first embodiment of the present disclosure;

FIG. 3 is a perspective view of a probe according to the first embodiment of the present disclosure;

FIG. 4 is a view of showing various cross-sections of a core wire used in the probe according to the first embodiment of the present disclosure;

FIG. 5 is a view of showing various shapes of the probe according to the first embodiment of the preset disclosure;

FIG. 6 is a view of showing various end tips of the probe according to the first embodiment of the present disclosure;

FIG. 7 is a view of partially showing a probe supporter for supporting the probe according to the first embodiment of the present disclosure;

FIG. 8 is a cross-sectional view of a probe according to a second embodiment of the present disclosure;

FIG. 9 is a cross-sectional view of a probe according to a third embodiment of the present disclosure; and

FIGs. 10 and 11 are a perspective view and a partial cross-sectional view of a probe according to a fourth embodiment of the present disclosure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Below, a testing device 100 according to embodiments of the present disclosure will be described with reference to the accompanying drawings.

FIG. 2 is a testing device 100 with a probe according to a first embodiment of the present disclosure. As shown therein, the testing device 100 includes a plurality of probes 110, a first supporting member 120 for supporting one end of the probe 110, and a second supporting member 130 for supporting the other end of the probe 110.

The probe 110 includes an elastic transformable portion 112 previously transformed in a certain direction at a middle portion, a sliding contact portion 114 penetrating and protruding from the first supporting member 120, and a stationary contact portion 116 penetrating and protruding from the second supporting member 130. Of course, the elastic transformable portion 112 may be not previously transformed. The sliding contact portion 114 is configured to contact an object to be tested, for example, a terminal (or pad) of a semiconductor wafer, and moves sliding within a first through hole 122 of the first supporting member 120. That is, if the object to be tested presses an end of the sliding contact portion 114 for a test, the sliding contact portion 114 slides within the first through hole 122 and thus the elastic transformable portion 112 is elastically transformed. The stationary contact portion 116 is configured to make its protruding ends be in contact with a testing contact point, for example, a terminal (or pad) of a testing circuit substrate while being stationarily supported in a second through hole 132 of the second supporting member 130.

The first supporting member 120 is made of an insulating material and shaped like a plate formed with a plurality of circular first through holes 122 through which the sliding contact portions 114 of the plurality of probes 110 pass.

The second supporting member 130 is made of an insulating material and shaped like a plate formed with a plurality of circular second through holes 132 in which the stationary contact portions 116 of the plurality of probes 110 are stationary. For example, the stationary contact portion 116 is bonded to the second through hole 132 by adhesive.

FIG. 3 is a perspective view of the probe 110 of FIG. 2. As shown therein, the probe 110 includes a conductive core 111 shaped like a cylindrical bar, an elastic plating layer 113 made of a material having higher elasticity than the core 111 and plated on and/or around the outer surface of the core 111, and a ductile plating layer 115 made of a material having lower elasticity than the elastic plating layer 113 and plated on and/or around the outer surface of the elastic plating layer 113. Further, as necessary, the probe 110 may include an additional laminate portion 117 on and/or around the outer surface of the ductile plating layer 115. The additional laminate portion 117 may include a second elastic plating layer 113-2, and a second ductile plating layer 115-2. The probe 110 may include an insulating layer 119 on and/or around the outer surface of the additional laminate portion 117.

The core 111 is made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

The elastic plating layer 113 is made of a highly elastic material, for example, a Pd (palladium) alloy, a Ni (nickel) alloy, etc.

The ductile plating layer 115 is made of a material similar to the highly conductive core 111, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof. Of course, the ductile plating layer 115 may be made of a Pd (palladium) alloy group, a Ni (nickel) alloy group, etc., which has lower elasticity and higher conductivity than the elastic plating layer 113.

The additional laminate portion 117 is configured to adjust the elasticity or resistance that cannot be achieved by the limit of the plating laminate thickness. The additional laminate portion 117 is additionally laminated as second elastic plating layer 113-2 and second ductile plating layer 115-2. The additional laminate portion 117 may be made of the same materials as the elastic plating layer 113 and the ductile plating layer 115. As necessary, the additional laminate portion 117 may include a plurality of layers different in elasticity and conductivity from the elastic plating layer 113 and the ductile plating layer 115.

The insulating layer 119 is configured to prevent a short circuit between the adjacent probes 110 when the plurality of probes 110 are arranged at fine pitches. For example, the insulating layer may be made of Teflon, synthetic resin, rubber, etc.

FIG. 4 is a view of showing various cross-sections of the core 111 used in the probe according to the first embodiment of the present disclosure. As shown therein, the core 111 may be manufactured with a bar having a hexagonal cross-section (a), a circular cross-section (b), a quadrangular cross-section(c), or a star-shaped cross-section (d). Of course, the core 111 may have an elliptical, triangular or freeform cross-section besides the above four kinds of cross-section. If the core 111 has the star-shaped cross-section (d), recessed portions may increase in thickness when the elastic plating layer 113, the ductile plating layer 115, and the additional laminate portion 117 are plated.

transformable portion 112 of a straight line type (a), a "V"-shaped curve type (b), a "L"-shaped curve type (C), and an "S"-shaped curve type (d). Of course, the elastic transformable portion 112 may be manufactured to have various shapes of "W"-shaped curve type or the like besides the above four kinds of type. The probe 110 having the elastic transformable portion 112 may be manufactured by making the elastic transformable portion in the core 111 and then plating the core 111 with the elastic plating layer 113, the ductile plating layer 115 and the additional laminate portion 117, or may be manufactured by first completing a plating process and then performing a press die and heat treatment to make the elastic transformable portion 112.

FIG. 6 is a view of showing various end tips of the probe 110 according to the first embodiment of the present disclosure. As shown therein, a testing contact point to be tested or an end of the probe 110 to contact the testing contact point may be formed with a triangular single tip (a), "M"-shaped double tips (b), a rectangular single tip (c) or a semi-circular single tip (d). Of course, the probe 110 may include an end tip having various shapes such as triple tips, a crown tip, etc. besides the above four shapes. The probe 110 may be manufactured by forming the end tip in the core 111 and then plating the core 111 having the end tip with the elastic plating layer 113, the ductile plating layer 115, and the additional laminate portion 117.

FIG. 7 is a view of partially showing a probe supporter 120 for supporting the probe 110 according to the first embodiment of the present disclosure. As shown in FIG. 2, the opposite ends of the probe 110 having the circular cross-section are inserted in the circular through

holes

122 and 132 of the

probe supporters

120 and 130. In this case, since the probe 110 has the circular cross-section, the through

holes

122 and 132 of the

probe supporters

120 and 130 are also manufactured to have circular shapes. Typically, if the through

holes

122 and 132 are big, there are no difficulties in forming them to have a quadrangular or circular shape. However, it is very difficult to form the quadrangular through hole at a pitch of hundreds of nm or less. On the other hand, it is easy to form the circular through hole according to the present disclosure by drilling or laser machining.

FIG. 8 is a cross-sectional view of a probe 200 according to a second embodiment of the present disclosure. As shown therein, the probe 200 includes a core 210, and a plurality of plating

layers

220, 230 and 240 laminated on and/or around the core 210, and an insulating layer 250.

The core 210 includes a first contact portion 212 configured to contact a first contact point, a second contact portion 214 configured to contact a second contact point, and an elastic transformable portion 216 configured to be transformed by press in a lengthwise direction of the first contact portion 212 or the second contact portion 214 during a test. The elastic transformable portion 216 includes all parts substantially transformed by the press. In FIG. 8, a dotted line 217 indicates a part where main transformation occurs, and a solid line 218 indicates a boundary between a part to be transformed and a part not to be transformed. Here, the elastic transformable portion 216 may have a shape before a previously transformed shape. The core 210 is made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

The plurality of plating

layers

220, 230 and 240 includes an elastic plating layer 220, a ductile plating layer 230 and an additional laminate portion 240.

The elastic plating layer 220 includes a first elastic plating layer 222 plated on and/or around the first contact portion 212, a second elastic plating layer 224 plated on and/or around the second contact portion 214, and a third elastic plating layer 226 plated on and/or around the elastic transformable portion 216. The elastic plating layer 220 is for example made of a Pd (palladium) alloy, a Ni (nickel) alloy, etc.

The ductile plating layer 230 may include a first ductile plating layer 232 plated on and/or around the first contact portion 212, a second ductile plating layer 234 plated on and/or around the second contact portion 214, and a third ductile plating layer 236 plated on and/or around the elastic transformable portion 216. The ductile plating layer 230 is made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

The additional laminate portion 240 includes a first laminated plating layer 242 plated on and/or around the first contact portion 212, a second laminated plating layer 244 plated on and/or around the second contact portion 214, and a third laminated plating layer 246 plated on and/or around the elastic transformable portion 216. The first and second laminated plating

layers

242 and 244 are made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof. The third laminated plating layer 246 may be for example made of a Pd (palladium) alloy, a Ni (nickel) alloy, etc. Like this, the plating layers 222, 224, 232, 234, 242 and 244 plated on and/or around the first contact portion 212 and the second contact portion 214 which are not elastically transformed may be improved in conductivity rather than elasticity, and the plating layers 226, 236 and 246 plated on and/or around the elastic transformable portion 216 may be improved in elasticity rather than conductivity. To this end, the materials plated on and/or around the first contact portion 212 and the second contact portion 214 are different from the material plated and/or around on the elastic transformable portion 216 in the additional laminate portion 240 of FIG. 8. Here, the plating with the different materials may be performed as follows. First, the third ductile plating layer 236 on and/or around the elastic transformable portion 216 is coated with a plating cover, and then the first and second ductile plating layers 232 and 234 on and/or around the first contact portion 212 and the second contact portion 214 are plated with a highly conductive first material. Next, the plating cover coated on and/or around the third ductile plating layer 236 is peeled off, and the first material layer on and/or around the first contact portion 212 and the second contact portion 214 is coated with a plating cover. Last, the third ductile plating layer 236 on and/or around the elastic transformable portion 216 is plated with a highly elastic second material. In FIG. 8, the additional laminate portion 240 is used to differently apply the elasticity and the conductivity according to the portions of the probe 200. Alternatively, the elastic plating layer 220 and the ductile plating layer 230 may be differently applied according to the portions of the probe 200.

The insulating layer 250 is the same as that of the probe 110 according to the first embodiment, and thus repetitive descriptions thereof will be avoided.

FIG. 9 is a cross-sectional view of a probe 300 according to a third embodiment of the present disclosure. As shown therein, the probe 300 according to the third embodiment of the present disclosure includes a core 310, a plurality of plating

layers

320, 330 and 340 laminated on and/or around the core 310, and an insulating layer 350.

The core 310 includes a first contact portion 312 configured to contact a first contact point, a second contact portion 314 configured to contact a second contact point, and an elastic transformable portion 316 configured to be transformed by press in a lengthwise direction of the first contact portion 312 or the second contact portion 314 during a test. The elastic transformable portion 316 includes all parts substantially transformed by the press. Here, the elastic transformable portion 316 may have a shape before a previously transformed shape. The first contact portion 312 and the second contact portion 314 have a larger cross-section than the elastic transformable portion 316. The first contact portion 312 and the second contact portion 314 are coated with only the insulating layer 350 without separate plating, and the elastic transformable portion 316 may be plated with a laminate of an elastic plating layer 320, a ductile plating layer 330 and an additional plating portion 340 so as to improve elasticity. The core 310 is made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

The plurality of plating

layers

320, 330 and 340 includes the elastic plating layer 320, the ductile plating layer 330 and the additional laminate portion 340.

The elastic plating layer 320 is for example made of a Pd (palladium) alloy, a Ni (nickel) alloy, etc.

The ductile plating layer 330 is made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

The additional laminate portion 340 is made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

FIGs. 10 and 11 are a perspective view and a partial cross-sectional view of a probe 400 according to a fourth embodiment of the present disclosure. As shown therein, the probe 400 includes a core 410, a plurality of plating

layers

420, 430 and 440 laminated on and/or around the core 410, and an insulating layer 450.

The core 410 includes at least one slot 417 extending in a lengthwise direction, and an elastic transformable portion including a plurality of bridges 418 configured to form the slot 417. Therefore, when press is given in the lengthwise direction, the plurality of bridges 418 is transformed. The core 410 is made of a highly conductive material, for example, Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.

The plurality of plating

layers

420, 430 and 440 includes an elastic plating layer 420, a ductile plating layer 430 and an additional laminate portion 440. The plurality of plating

layers

420, 430 and 440 may be plated on and/or around only the elastic transformable portion 416 as shown in FIG. 11, or may be additionally plated on and/or around the first contact portion 412 and the second contact portion 414.

As shown in FIG. 11, the elastic plating layer 420, the ductile plating layer 430 and the additional laminate portion 440 are plated on and/or around the elastic transformable portion 416 of the core 410. The bridge 418 configured to form the slot 417 is excellent in conductivity by the core 410, and is also excellent in elasticity by the elastic plating layer 420.

As described above, the probe according to the present disclosure is convenient to make its opposite ends (i.e. contact tips) be in contact with an object to be tested and decreases in contact resistance since the circular core is plated with the elastic layer and the conductive layer. Further, the probe according to the present disclosure is more improved in durability than the conventional probe having the quadrangular laminated cross-section. In particular, it is easy to manufacture the probe supporter for supporting the MEMS probe to be applied to very fine pitches.

Although a few exemplary embodiments have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these exemplary embodiments without departing from the principles and spirit of the disclosure.

Therefore, the scope of the present disclosure has to be not limited to the foregoing exemplary embodiments but defined in the appended claims and their equivalents.

Claims

A probe for testing an electric characteristic of an object to be tested, the probe comprising:

a core with conductive properties and shaped like a bar; and

an elastic plating layer made of a material having higher elasticity than the core and plated on the core.
The probe according to claim 1, further comprising a ductile plating layer made of a material having lower elasticity than the elastic plating layer and plated to the core.
The probe according to claim 2, further comprising at least one additional laminate portion plated to the ductile plating layer or the elastic plating layer on the core.
The probe according to claim 3, further comprising an insulating layer configured to surround an outer surface of the additional laminate portion.
The probe according to any one of claims 1 to 4, wherein the core comprises at least one end tip configured to be in contact with the object to be tested.
The probe according to any one of claims 1 to 4, wherein the core comprises one of a circular cross-section, an elliptical cross-section, a polygonal cross-section, and a star-shaped cross-section.
The probe according to any one of claims 1 to 4, wherein

the elastic plating layer is plated with a Pd (palladium) alloy or a Ni (nickel ) alloy,

the ductile plating layer is plated with at least one of Au (gold), Pt (platinum), Ag (gold), Cu (copper), and Al (aluminum), and

the core comprises Au (gold), Pt (platinum), Ag (silver), Cu (copper), Al (aluminum), Fe (iron), Be (beryllium), Rh (rhodium) or the like, or an alloy thereof.
The probe according to claim 1, wherein

the core comprises a first contact portion configured to contact a first contact point, a second contact portion configured to contact a second contact point, and an elastic transformable portion configured to be transformed by press in a lengthwise direction during a test, and

the elastic plating layer comprises a first elastic plating layer plated on the first contact portion, a second elastic plating layer plated on the second contact portion, and a third elastic plating layer plated on the elastic transformable portion.
The probe according to claim 8, wherein the ductile plating layer comprises a first ductile plating layer plated to the first contact portion, a second ductile plating layer plated to the second contact portion, and a third ductile plating layer plated to the elastic transformable portion.
The probe according to claim 9, wherein the first and second elastic plating layers, the first and second ductile plating layers and first and second additional laminate portions, which are plated to the first contact portion and the second contact portion, have lower elasticity and higher conductivity than the third elastic plating layer, the third ductile plating layer and a third additional laminate portion, which are plated to the elastic transformable portion.
The probe according to claim 9, wherein the elastic transformable portion has a smaller cross-section than the first contact portion or the second contact portion.
The probe according to claim 1, wherein the core comprises a first contact portion configured to contact a first contact point, a second contact portion configured to contact a second contact point, and an elastic transformable portion configured to be transformed by press in a lengthwise direction during a test, and

the elastic plating layer is plated on only the elastic transformable portion.
The probe according to claim 1, wherein the core comprises a first contact portion configured to contact a first contact point, a second contact portion configured to contact a second contact point, and an elastic transformable portion configured to be transformed by press in a lengthwise direction during a test, and

the elastic transformable portion comprises at least one slot extending in the lengthwise direction.
The probe according to claim 13, wherein the elastic plating layer is plated on a plurality of bridges configured to form the slot.