Probe card and designing method thereof, and method and system for testing specimen using probe card

Abstract

To provide a probe card for solving a problem in which an electric test cannot be performed effectively in a conventional cantilever-type probe card because of miniaturization of a pad size and a pitch by effectively and stably testing a specimen by combining a cantilever probe of a cantilever-type probe card and a perpendicular probe head.SOLUTION: Provided is a probe card including a circuit board, a cantilever-type adapter electrically connected to the circuit board, and a perpendicular probe head electrically connected to the cantilever type adapter. The perpendicular probe head includes a probe holder and multiple perpendicular probes. The cantilever-type adapter includes a mount base and multiple cantilever-type adapter needles, and the respective cantilever-type adapter needles include a fixed segment and an exposed segment. The fixed segment is fixed to the mount base, the exposed segment is positioned outside the mount base, the fixed segment enters from the side of the mount base and forms a contact on the bottom face of the mount base.SELECTED DRAWING: Figure 1D

Description

[Technical field]

[0001] The present invention relates to a probe card, a method for designing a probe card, and a test method and test system using the probe card. [Background technology]

[0002] Wafer acceptance test (WAT) is a front-end inspection of wafers and is an important process in the semiconductor manufacturing process. It is mainly used to ensure the quality and performance of the test object (i.e., wafer) and to find potential problems early before the wafer enters the subsequent processes (cutting, packaging, etc.), thereby reducing costs and improving product quality. Wafer acceptance test mainly tests the contacts arranged on the wafer scribe line, and the test method is to contact the probe of a probe card with the contact of the wafer scribe line and connect the other end of the probe card to the test device of the wafer acceptance test system to measure the wafer.

[0003] With the advancement of semiconductor manufacturing processes, the size of wafers is becoming smaller and smaller, and the pad size and pad pitch of wafers are becoming finer. Therefore, when a cantilever probe of a conventional cantilever probe card (CPC) pierces a wafer with a needle to contact a pad on the wafer, the vertical relative movement of the probe head with the wafer causes the probe head to move laterally, exceeding the pad area, and even causing an ineffective contact with the pad. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention provides a probe card that combines a cantilever probe of a cantilever type probe card with a vertical probe head to effectively and stably test a specimen, and solves the problem that electrical testing cannot be effectively performed with conventional cantilever type probe cards due to the miniaturization of pad size and pitch. [Means for solving the problem]

[0005] For this reason, the present invention provides a probe card suitable for performing a wafer acceptance test, the probe card including a circuit board, a cantilever adapter electrically connected to the circuit board, and a vertical probe head electrically connected to the cantilever adapter, the vertical probe head including a probe holder and a vertical probe. The probe holder includes an upper guide plate unit and a lower guide plate unit, the upper guide plate unit has an upper guide plate and an upper guide hole penetrating the upper guide plate, the lower guide plate unit has a lower guide plate and a lower guide hole penetrating the lower guide plate, the upper guide plate unit and the lower guide plate unit have upper and lower surfaces, respectively, and a storage space is formed between the lower surface of the upper guide plate unit and the upper surface of the lower guide plate unit. The vertical probe includes a needle tail portion, a needle body, and a needle head portion, the needle tail portion is provided with an upper guide hole, the needle body is located in the storage space, and the needle head portion is provided with a lower guide hole. The cantilever adapter has a mounting base and a cantilever adapter needle, the cantilever adapter needle having a fixed portion and an exposed portion, the fixed portion is fixed to the mounting base, the exposed portion is located outside the mounting base, and the fixed portion enters from a side edge of the mounting base and forms a contact on a bottom surface of the mounting base.

[0006] In addition, if the distance between adjacent cantilever-type adapter needles is not properly adjusted, coupling capacitance is likely to occur, which will affect the results of the electrical test, so it is necessary to adjust the configuration of adjacent cantilever-type adapter needles to reduce the coupling capacitance value of adjacent cantilever-type adapter needles, reduce the energy accumulation effect between the probes, and further improve the stability of the leakage current test.

[0007] In one embodiment, the cantilever adapter has a first adapter needle and a second adapter needle, the first adapter needle is adjacent to the second adapter needle and does not contact each other, the fixed portion of the first adapter needle and the second adapter needle have needle entry portions entering from a side of the fixed portion, each cantilever adapter needle entry portion further includes a head region away from the side of the fixed portion and a tail region adjacent to the fixed portion, the needle entry portions of the first adapter needle and the second adapter needle have a head minimum distance at corresponding positions of the two needle entry portions, and the tail regions of the needle entry portions of the first adapter needle and the second adapter needle have a tail minimum distance that is greater than the head minimum distance. In another embodiment, the minimum distance at corresponding positions of the needle entry portions of the first adapter needle and the second adapter needle tapers off from entering the side of the fixed portion.

[0008] In addition, to avoid the problem that when the cantilever type adapter needle is electrically contacted with the vertical probe of the vertical probe head, the needle head of the cantilever type adapter needle may shift in position due to fluctuations in contact force, resulting in unstable contact, in one embodiment, the cantilever type adapter is installed on a circuit board, the mounting base includes a base having an upper surface facing the circuit board and a first through hole, the fixing part is installed in the first through hole and extends to the upper surface of the base, and the fixing part covers the fixing part.

[0009] In addition, in order to ensure that the structure of the probe card itself is suitable for leakage current testing, a pad ring for welding a cantilever-type adapter needle is installed on the underside of the circuit board, and even if leakage current occurs, it can be guided to ground by a protective circuit pattern (guard), ensuring that the leakage current does not flow to other pad rings, and ensuring that the leakage current is within specifications. In one embodiment, the circuit board further includes a plurality of leakage current prevention contacts, each of the plurality of leakage current prevention contacts is installed on a bottom plate, and the bottom plate is installed on the circuit board via an adhesive material, and the leakage current prevention contacts further include a signal circuit pattern surrounded by the protective circuit pattern. If the leakage current prevention contacts do not meet the leakage current test criteria, the bottom plate is removed and replaced with a bottom plate having a new leakage current prevention contact, providing a repair mechanism that can overcome the fact that the contact part does not meet the leakage current test criteria.

[0010] In addition, the flatness of the reinforcing member is smaller than that of the circuit board, and when the mounting base is installed on the reinforcing member, the bottom surface of the fixing part of the mounting base has a first flatness, and when the mounting base is installed on the circuit board, the bottom surface of the fixing part of the mounting base has a second flatness, and the first flatness is smaller than the second flatness. When the mounting base is installed on the probe card of the circuit board to replace the vertical probe head, if the second flatness of the bottom surface of the fixing part is not good, the vertical probe of the vertical probe head cannot be stably electrically connected to the cantilever type adapter, which may deteriorate the stability of the wafer acceptance test. Therefore, when the mounting base is installed on the probe card of the reinforcing member to replace the vertical probe head, the first flatness of the bottom surface of the fixing part becomes relatively good, which allows the vertical probe of the vertical probe head to be stably electrically connected to the cantilever type adapter, and further improves the stability of the wafer acceptance test.

[0011] In one embodiment, the material of each cantilever-type adapter needle is an alloy of one or a combination of the following: beryllium, copper, rhenium, tungsten, gold, and silver.

[0012] In one embodiment, the contact point of each cantilever adapter needle is the end of the needle body of the fixed portion or the contact point of each cantilever adapter needle is a contact pad coupled to the end of the needle body of the fixed portion.

[0013] In one embodiment, the fixed portion is tapered.

[0014] In one embodiment, the hardness of the cantilever adapter needle is greater than 245 MPa and the resistance of the cantilever adapter needle is less than 200 mΩ.

[0015] In addition, when the probe card of the present invention is used to perform a wafer acceptance test, in order to prevent the vibration caused by the test environment from affecting the cantilever adapter needle, the hardness of the cantilever adapter needle is set to be higher than 245 MPa, thereby preventing the test result from being unstable due to the vibration of the cantilever adapter needle. In order to prevent the leakage current situation between two adjacent cantilever adapter needles, i.e., the current flowing from one cantilever adapter needle to the other cantilever adapter needle, the resistance of the cantilever adapter needle is set to be less than 200 mΩ, thereby preventing the leakage current between adjacent cantilever adapter needles to the maximum extent possible.

[0016] In order to solve the problem of interference of coupling capacitance between adjacent cantilever adapter needles and improve the accuracy of electrical measurement, the effect of coupling capacitance is reduced by adjusting the change of the distance (gap) between the cantilever adapter needles. In one embodiment, the present invention provides a method for designing a probe card, the probe card includes a circuit board, a cantilever adapter, and a vertical probe head, the cantilever adapter is electrically connected to the circuit board, the vertical probe head is electrically connected to the cantilever adapter, the cantilever adapter has a mounting base and a plurality of cantilever adapter needles, the plurality of cantilever adapter needles include two mutually adjacent first and second adapter needles, the method for designing the probe card includes: based on a distance between one end of the first adapter needle and one end of the second adapter needle, adjusting an actual coupling capacitance between the first adapter needle and the second adapter needle under a condition that the distance between one end of the first adapter needle and one end of the second adapter needle is fixed, to satisfy a threshold value of the coupling capacitance. In another embodiment, the mounting base of the cantilever type adapter has a fixed portion, and each cantilever type adapter needle in turn has a fixed portion and an exposed portion, the fixed portion is fixed to the fixed portion of the mounting base and the exposed portion is outside the fixed portion, and the exposed portion is used for electrical connection to a circuit board, and the step of adjusting the actual coupling capacitance between the first adapter needle and the second adapter needle includes adjusting the relative distance between the fixed portions of the first adapter needle and the second adapter needle to adjust the actual coupling capacitance between the first adapter needle and the second adapter needle.

[0017] The present invention provides a testing method including the steps of providing the above-mentioned probe card, contacting the needle heads of the vertical probes of a plurality of the probe cards with corresponding conductive contacts of the test specimen, and transmitting a test signal to the test specimen via the probe card.

[0018] The present invention provides a test system including a mounting stage and a probe card. A test object is mounted on the mounting stage. The vertical probe of the probe card is brought into contact with the test object to electrically connect the test object to the probe card. Effect of the Invention

[0019] The probe card of the present invention combines the cantilever probe of a cantilever-type probe card with a vertical probe head to effectively and stably test a specimen, and solves the problem that electrical testing cannot be effectively performed with conventional cantilever-type probe cards due to the miniaturization of pad size and pitch. [Brief description of the drawings]

[0020] [Figure 1A] FIG. 2 is an exploded view of a first embodiment of the probe card of the present invention. [Figure 1B] 1 is a perspective view of a first embodiment of a probe card of the present invention, seen from a different angle. [Figure 1C] 1 is a perspective view of a first embodiment of a probe card of the present invention, seen from a different angle. [Figure 1D] FIG. 1C is a cross-sectional view of FIG. [Figure 1E] FIG. 1C is a cross-sectional view of FIG. [Figure 1F] FIG. 4 is a cross-sectional view of a second embodiment of the probe card of the present invention. [Figure 2A] FIG. 4 is an explanatory diagram of a third embodiment of the probe card of the present invention. [Figure 2B] FIG. 13 is an explanatory diagram of a fourth embodiment of the probe card of the present invention. [Figure 3A] FIG. 2 is a bottom view of the first embodiment of the probe card of the present invention. [Figure 3B] 1 is an illustration of one embodiment of a leakage current prevention contact of a probe card of the present invention. [Figure 4A] FIG. 13 is an explanatory diagram of a fifth embodiment of the probe card of the present invention. [Figure 4B] FIG. 13 is an explanatory diagram of a sixth embodiment of the probe card of the present invention. [Diagram 5] 1 is a flowchart of an embodiment of a method for designing a probe card of the present invention. [Figure 6] FIG. 1 is an explanatory diagram of an embodiment of a test system of the present invention. [Figure 7] 1 is a flowchart of an embodiment of a method for testing a semiconductor wafer using a probe card of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In order to make the disclosure of the present invention more detailed and complete, various exemplary embodiments are provided below, but the various exemplary embodiments are not used to limit the present invention.

[0022] 1A to 1E are referred to at the same time. FIG. 1A is an exploded view of a first embodiment of the probe card 2 of the present invention. FIG. 1B and FIG. 1C are perspective views of the first embodiment of the probe card 2 of the present invention seen from different angles, FIG. 1B is a perspective view of the probe card 2 seen from diagonally above, and FIG. 1C is a perspective view of the probe card 2 seen from diagonally below. FIG. 1D and FIG. 1E are cross-sectional views of FIG. 1B, specifically, the cross-sectional views are taken from one end point on the circumference of the disk-shaped circuit board 20 along the vertical direction to the other end point of the circumference of the circuit board 20 after the probe card 2 is placed parallel to the ground as shown in FIG. 1 and all the parts are assembled, and the distance between the two end points is the diameter of the circumference of the circuit board 20. The cross-sectional view of FIG. 1D clearly shows the detailed structures of the circuit board 20, the reinforcing member 25, and the cantilever-type adapter 21 and the positional relationship between each member, and the cross-sectional view of FIG. 1E clearly shows the detailed structure of the vertical probe head 22.

[0023] The probe card 2 includes a circuit board 20, a cantilever type adapter 21, and a vertical probe head 22. The cantilever converter 21 is electrically connected to the circuit board 20. The vertical probe head 22 is electrically connected to the cantilever type adapter 21.

[0024] The circuit board 20 has an upper surface 200 and a lower surface 201. The circuit board 20 further includes leakage current prevention contacts 26a, 26b, a coaxial cable 27, and a first via 203. The first via 203 is formed between the upper surface 200 and the lower surface 201 and is provided on the circuit board 20, the leakage current prevention contact 26a is provided on the upper surface 200, and the leakage current prevention contact 26b is provided on the lower surface 201. One end of the coaxial cable 27 is electrically connected to the leakage current prevention contact 26a, and the other end of the coaxial cable 27 is electrically connected to the leakage current prevention contact 26b, and the coaxial cable 27 penetrates the circuit board 20 through the first via 203.

[0025] In this embodiment, one of the purposes of using the leakage current prevention contacts 26a, 26b is to prevent leakage current. Specifically, before the wafer acceptance test, the probe card 2 may first undergo a leakage current test to check whether the leakage current of the probe card complies with the standard specification; otherwise, when the wafer acceptance test is performed, the leakage current of the probe card may damage the wafer. For example, the standard specification requires that the leakage current is 1 pA (1x10 ‐12 In other possible embodiments, the circuit board 20 may use other types of contacts and is not limited to the leakage current prevention contacts 26a, 26b.

[0026] One of the purposes of using the coaxial cable 27 in this embodiment is that it is suitable for high frequency testing. In other possible embodiments, the circuit board 20 is not limited to the coaxial cable 27 and may use other types of electrical cables, which may not be suitable for high frequency testing.

[0027] The cantilever adapter 21 includes a mounting base 210 and a cantilever adapter needle 211. In some embodiments of the present invention, the material of the cantilever adapter needle 211 is an alloy of one or a combination of beryllium, copper, rhenium, tungsten, gold, and silver. Also, in some embodiments of the present invention, the hardness of the cantilever adapter needle 211 is greater than 245 MPa, and the resistance of the cantilever adapter needle 211 is less than 200 mΩ.

[0028] In this embodiment, the mounting base 210 includes a fixing portion 210A and a base 210B. The material of the fixing portion 210A is a fixing structure formed from a polymer material (e.g., epoxy resin). The base 210B has an annular structure, and a hollow area CA surrounded by the base 210B is defined as a first through hole 210b, and the epoxy resin is filled in the first through hole 210b. The probe card of this embodiment further includes a reinforcing member 25 that is removably installed in the through hole 202 of the circuit board 20, the mounting base 210 is connected to the reinforcing member 25, the reinforcing member 25 has a through hole 250, and an outer wall is provided in the through hole 202 of the circuit board 20, the fixing portion 210A is filled in the through hole 202, and some of the epoxy resin overflows from a gap between the upper surface of the base 210B and the reinforcing member 25 to form an overflow area OP.

[0029] It should be noted that those skilled in the art can appropriately modify the structure of the mounting base 210 of this embodiment, and may choose not to use the reinforcing member 25, or may change the structure or position of the reinforcing member 25 relative to the mounting base, as long as the cantilever-type adapter needle 211 can be fixed and the circuit board 20 and the vertical probe head 22 can be stably electrically connected. For example, in another possible embodiment of the present invention, the reinforcing member 25 of the probe card may be configured to be non-removable. As another example, in another possible embodiment of the present invention, the probe card may not use the reinforcing member 25, and a gap is formed between the upper surface of the base 210B and the lower surface 201 of the circuit board 20, and some epoxy resin overflows from the gap to form an overflow area OP.

[0030] This embodiment has at least the following advantages compared to other possible embodiments of the present invention. First, the reinforcing member 25 is provided to enhance the fixing effect between the mounting base 210 and the circuit board 20, and improve the stability of the electrical connection between the contact 211 of the mounting base 210 and the needle tail 240 of the vertical probe 24 of the vertical probe head 22. Second, the structure of the reinforcing member 25 and its position in the through hole 202 of the circuit board 20 provide a better fixing effect and improved stability. Third, the reinforcing member 25 is removable, and compared to other possible embodiments of the present invention, the corresponding cantilever-type adapter 21 and reinforcing member 25 can be replaced on the same circuit board 20 according to different DUTs, which can save material costs. Specifically, the mounting base 210 of the cantilever-type adapter converter 21 is installed on the reinforcing member 25, and the exposed portion 211c of the cantilever-type adapter needle 211 is welded and unwelded from the leakage current prevention contact 26b, so that the reinforcing member 25 can be removed from the circuit board 20.

[0031] The cantilever type adapter needle 211 has a fixed portion 211a and an exposed portion 211c in this order, the fixed portion 211a is fixed to the fixed portion 210A of the mounting base 210, the exposed portion 211c extends outside the fixed portion 210A toward the circuit board 20, and the exposed portion 211c is used to electrically connect the contacts of the circuit board 20. The fixed portion 211a enters from the gap between the upper surface of the base 210B and the reinforcing member 25 (i.e., the side of the fixed portion 210A) and forms contacts 211d on the bottom surface (or lower surface 210d) of the fixed portion 210A of the mounting base 210, and each contact 211d is used to electrically contact the needle tail portion 240 of each vertical probe 24.

[0032] In this embodiment, the fixed portion 211a is tapered, such as a cone or a pyramid. It should be noted that the fixed portion 211a is not limited to having a tapered structure, and in other possible embodiments of the present invention, those skilled in the art can use a relatively thin needle according to the reduction of the pitch of the pads of the wafer, and does not necessarily have a tapered structure. The fixed portion 211a of the probe card in this embodiment adopts a tapered structure, and compared with other possible embodiments of the present invention, the fixed portion 211a can adjust the size of the contact point between the cantilever-type adapter needle 211 and the needle tail of the vertical probe 22, and achieve the stability of the electrical contact.

[0033] In this embodiment, the fixed portion 211a is a probe having an inclined structure, that is, the fixed portion 211a includes a needle entry portion 211b and a contact portion 211g connected to the needle entry portion 211b at an angle, and the contact portion 211g can be regarded as the needle head of the cantilever type adapter needle 211. However, the present invention is not limited thereto, and for example, in another possible embodiment of the present invention, the needle entry portion 211b is a needle body structure having a curvature, one end of which is bent at a curvature to form a contact point by the protruding fixed portion 210A, and electrically contacts the needle tail portion 240 of each vertical probe 24. Compared with other possible embodiments of the present invention, the inclined structure of this embodiment makes it easier to align the contact point 211d of the cantilever type adapter needle 211 when the cantilever type adapter needle 211 is attached to the mounting base 210.

[0034] The vertical probe head 22 includes a probe holder 23 and a plurality of vertical probes 24. The probe base 23 includes an upper guide plate unit 230 and a lower guide plate unit 231. The upper guide plate unit 230 has at least one upper guide plate 230a and a plurality of upper guide holes 230b penetrating at least one upper guide plate. The lower guide plate unit 231 has at least a lower guide plate 231a and a plurality of lower guide holes 231b penetrating at least one lower guide plate 231a, the upper guide plate unit 230 has an upper surface 230c and a lower surface 230d, and the lower guide plate unit 231 has an upper surface 231c and a lower surface 231d. An accommodation space S is formed between the lower surface 230d of the upper guide plate unit 230 and the upper surface 231c of the lower guide plate unit 231. Each vertical probe 24 includes a needle tail portion 240, a needle body 241, and a needle head portion 242. The needle tail portion 240 is provided with an upper guide hole 230b which is used for electrical contact with the cantilever type adapter 21, the needle body 241 is positioned in the accommodation space S, and the needle head portion 242 is provided with a lower guide hole 231b for electrical contact with the test subject DUT.

[0035] In this embodiment, the vertical probe head 22 is installed on the reinforcing member 25. In detail, a fixing member (which may be, for example, the fixing member 28) passes through the via 220 of the vertical probe head 22 and the through hole 2100 of the base 210B of the mounting base 210, and is fixed in the fixing hole 252 of the reinforcing member 25, or passes through the abutment ring 251 of the reinforcing member 25 and is fixed by a nut and a fixing member, so that the vertical probe head 22 is installed on the reinforcing member 25, and thus the vertical probe head 22 and the mounting base 210 are both directly installed on the reinforcing member 25, and the standard of flatness of the vertical probe head 22 and the mounting base 210 is determined by the reinforcing member 25. The flatness of the reinforcing member 25 is smaller than the flatness of the circuit board 20, and when the mounting base 210 is installed on the reinforcing member 25, the bottom surface 210d of the fixing portion 210A of the mounting base 210 has a first flatness, and when the mounting base 210 is installed on the circuit board 20, the bottom surface 210d of the fixing portion 210A of the mounting base 210 has a second flatness, and the first flatness is smaller than the second flatness. When the probe card with the mounting base 210 installed on the circuit board 20 is replaced with the vertical probe head 22, the vertical probes 24 of the vertical probe head 22 cannot be stably electrically connected to the cantilever type adapter 21 because the second flatness of the bottom surface 210d of the fixing part is not good, which may reduce the stability of the wafer acceptance test. When the mounting base 210 is installed on the probe card 2 of the reinforcing member 25 and the vertical probe head 22 is replaced, the vertical probes 24 of the vertical probe head 22 can be stably electrically connected to the cantilever type adapter 21 because the first flatness of the bottom surface 210d of the fixing part is better, which further improves the stability of the wafer acceptance test.

[0036] In this embodiment, the contact 211d of each cantilever adapter needle 211 is an end of the fixed portion 211a, and the lowest point of the end of the fixed portion 211a is aligned flush with the bottom surface (or lower surface 210d) of the fixed portion 210A of the mounting base 210. In other possible embodiments of the present invention, the lowest point of the end of the fixed portion 211a may be located above or below the plane of the bottom surface (or lower surface 210d) of the fixed portion 210A of the mounting base 210. In another embodiment, as shown in FIG. 1F, the contact 211d of the cantilever adapter needle 211 is an enlarged contact pad 211h, and the contact pad 211h is located below the bottom surface (or referred to as the lower surface 210d) of the fixed portion 210A of the mounting base 210. The design of the contact pad 211h can improve the stability of the electrical contact between the cantilever adapter needle 211 of the cantilever adapter 21 and the vertical probe 24 of the vertical probe head 22.

[0037] Please refer to FIG. 2A. FIG. 2A is an explanatory diagram of a third embodiment of the probe card of the present invention. In this embodiment, three cantilever type adapter needles 211 are taken as an example, but the number of cantilever type adapter needles 211 of the probe card of the present invention is not limited to three. The cantilever type adapter needle 211 includes a first adapter needle 211A and a second adapter needle 211B, and the first adapter needle 211A and the second adapter needle 211B are not in contact with each other. The fixed part 211a has a needle entry part 211b that enters from the side edge 2110 of the fixed part 210A. Note that the side edge 2110 described in this embodiment is not limited to the side edge where the needle enters on the left side shown in FIG. 1D, and as shown in FIG. 3A, the side edge may be any position on the 360-degree side edge of the fixed part 210A. The needle entry portions 211b of the multiple cantilever type adapter needles 211 further include a head region 211e away from the side 2110 of the fixed portion 210A and a tail region 211f adjacent to the side 2110 of the fixed portion, and the head regions 211e of the needle entry portions 211b of the first adapter needle 211A and the second adapter needle 211B have a head minimum distance d at corresponding positions of the two needle entry portions 211b, and the tail regions 211f of the needle entry portions 211b of the first adapter needle 211A and the second adapter needle 211B have a tail minimum distance D, and the tail minimum distance D is greater than the head minimum distance d, but there is no specific limit on the change in probe distance between the minimum distances D and d. In this embodiment, the distance between the shortest distance D and d is gradually decreased, that is, the shortest distance at the position corresponding to the needle entry portion 211b of the first adapter needle 211A and the second adapter needle 211B is gradually decreased from the position of the side edge 2110 of the fixed part to the head shortest distance d. The different design methods of the two can reduce the interference of the coupling capacitance between the probes and further improve the accuracy of the electrical test.

[0038] Please refer to FIG. 2B. FIG. 2B is an explanatory diagram of a third embodiment of the probe card of the present invention. In this embodiment, two cantilever type adapter needles 211 are taken as an example, but the number of cantilever type adapter needles 211 of the probe card of the present invention is not limited to two. In this embodiment, the change in the probe distance between the shortest distances D and d first gradually decreases from the tail shortest distance D to the head shortest distance d, and after reaching the shortest distance d in the middle area, it extends while maintaining parallelism to the contact portion 211g, so that it is another embodiment that reduces the coupling capacitance. In other words, in this embodiment, the multiple cantilever type adapter needles 211 have a first adapter needle 211A and a second adapter needle 211B, and the first adapter needle 211A and the second adapter needle 211B are adjacent to each other and do not contact each other, and the first adapter needle 211A and the second adapter needle 211B each have a fixed portion 211a and an exposed portion 211c. The fixed portion 211a includes a needle entry portion 211b and a contact portion 211g, the needle entry portion 211b further includes a head portion 211e that is away from the side 2110 of the fixed portion 210A and parallel to each other, and a tail portion 211f that is adjacent to the side 2110 of the fixed portion 210A and is not parallel to each other, and corresponding positions of the head region 211e of the needle entry portion 211b of the first adapter needle 211A and the second adapter needle 211B have a head minimum distance d, and the tail region 211f of the needle entry portion 211b of the first adapter needle 211A and the second adapter needle 211B have a tail minimum distance D, and the tail minimum distance D is greater than the head minimum distance d.

[0039] Also, this is to ensure that the contact portion 211g of the probe does not move laterally due to the bending of the cantilever of the cantilever type adapter needle 211 during measurement and cannot come into contact with the needle tail portion 240 of the vertical probe 24. In this embodiment, the cantilever type adapter 21 is installed on the circuit board 20, the base 210B of the mounting base 210 has an upper surface 210a facing the circuit board 20 and a first through hole 210b, and the fixing portion 210A is installed in the first through hole 210b and extends to the upper surface 210a of the base 210B, filling the gap 212 between the base 210B and the circuit board 20, allowing the fixing portion 211a to be covered by the fixing portion 210A, and further holding the contact portion 211g in a predetermined position. The gap 212 can also be used to pass the exposed portion 211c of the cantilever type adapter needle 211 and enter the fixing portion 210A.

[0040] Please refer to FIG. 3A and FIG. 3B. FIG. 3A is a bottom view of a first embodiment of the probe card of the present invention. FIG. 3B is an explanatory diagram of an embodiment of the leakage current prevention contact of the probe card of the present invention. In order to ensure that the probe card meets the leakage current test specification, the lower surface 201 of the circuit board 20 is provided with a pad ring for welding a cantilever-type adapter needle, and even if a leakage current occurs, it can be guided to ground by a protective circuit pattern (guard), ensuring that the leakage current does not flow to other pad rings, and ensuring that the leakage current is within the specification. In this embodiment, the upper surface 200 of the circuit board 20 has a plurality of leakage current prevention contacts 26a, and the lower surface 201 of the circuit board 20 has a plurality of leakage current prevention contacts 26b. Each of the leakage current prevention contacts 26a, 26b is provided on the circuit board 20 via a bottom plate 260 to form a leakage current prevention structure. In this embodiment, each of the leakage current prevention contacts 26a, 26b further includes a signal circuit pattern 261 surrounded by a protective circuit pattern 262. Among them, the bottom plate 260 and the signal circuit pattern 261 further include a conductive layer 263 and an insulating layer 264 formed on the conductive layer 263. The protective circuit pattern 262 is electrically connected to the conductive layer 263. The conductive layer 263 provides a vertical shielding function for the signal circuit pattern 261 under the insulating layer 264. The bottom plate 260 is installed on the surface of the circuit board 20. Note that the conductive layer 263 and the insulating layer 264 can be determined according to the usage requirements and have no specific limitations. The bottom plate 260 is installed on the circuit board 20 by an adhesive material. If the leakage current prevention contact does not meet the leakage current test specification, the bottom plate 260 can be removed and replaced with a bottom plate 260 having new leakage current prevention contacts 26a, 26b, providing a repair mechanism that can overcome the contact part not meeting the leakage current test specification. In addition, the leakage current prevention contacts 26a, 26b may be a combination of one signal circuit pattern 261 and a protection circuit pattern 262 installed on the bottom plate, or a plurality of signal circuit patterns 261 and protection circuit patterns 262 installed at intervals on the bottom plate, and there is no specific restriction and can be determined according to the actual test requirements.

[0041] Please refer to Fig. 1D, Fig. 3A and Fig. 3B together. In this embodiment, the circuit board 20 has a circuit board central axis CA1 along its thickness direction, the first leakage current prevention contact 26a has a first central axis CA2 along its thickness direction, the second leakage current prevention contact 26b has a second central axis CA3 along its thickness direction, and the radial distance d1 between the first central axis CA2 and the circuit board central axis CA1 is greater than the distance d2 between the second central axis CA3 and the circuit board central axis CA1. The coaxial cable 27 includes an axial core, an insulating layer and an outer conductor layer coaxially surrounding the core, and both ends of the core of the coaxial cable 27 are electrically connected to the signal circuit patterns 261 of the leakage current prevention contacts 26a and 26b, respectively, and both ends of the outer conductor layer of the coaxial cable 27 are electrically connected to the protection circuit patterns 262 of the leakage current prevention contacts 26a and 26b, respectively.

[0042] It should be noted that the method of installing the leakage current prevention contacts 26a, 26b is not limited to the first embodiment. Please refer to FIG. 4A. FIG. 4A is an explanatory diagram of a fifth embodiment of the probe card of the present invention. The fifth embodiment is similar to the first embodiment, and the difference is that both leakage current prevention contacts 26a, 26b are installed on the upper surface 200 of the circuit board 20. The circuit board 20 further includes a plurality of second vias 204 for passing the cantilever-type adapter needle 211. In this embodiment, the exposed portion 211c of the cantilever-type adapter needle 211 includes a first needle portion 211i and a second needle portion 211j, the first needle portion 211i is connected to the fixed portion 211a, and the second needle portion 211j is connected to the first needle portion 211i, and has an included angle θ. The second needle portion 211j is further electrically connected to the leakage current prevention contact 26b provided on the upper surface 200 through the second via 204. The leakage current prevention contact 26b is electrically connected to the leakage current prevention contact 26a via a coaxial cable 27. The multiple leakage current prevention contacts 26a, 26b include multiple first leakage current prevention contacts 26a on the upper surface 200 of the circuit board 20 and multiple second leakage current prevention contacts 26b on the upper surface 200 of the circuit board 20, both ends of each coaxial cable 27 are electrically connected to the first leakage current prevention contact 26a and the second leakage current prevention contact 26b, respectively, the center of the circuit board 20 has a circuit board central axis CA1 along its thickness direction, the first leakage current prevention contact 26a has a first central axis CA2 along its thickness direction, the second leakage current prevention contact 26b has a second central axis CA3 along its thickness direction, and the radial distance d1 between the first central axis CA2 and the circuit board central axis CA1 is greater than the distance d2 between the second central axis CA3 and the circuit board central axis CA1.

[0043] Please refer to FIG. 4B. FIG. 4B is an explanatory diagram of the sixth embodiment of the probe card of the present invention. The sixth embodiment is basically similar to the first embodiment, and the difference is that in this embodiment, the circuit board 20 can be a through hole or a blind via. The fixing member 28 penetrates the reinforcing member 25 and abuts against the abutment ring 251 on the upper surface 200 of the circuit board 20, and then is fixed in the fixing hole 205. In addition, the fixing method of the fixing member 28 is not limited thereto, and in other embodiments, the fixing member 28 penetrates the circuit board 20 and abuts against the lower surface 201 of the circuit board 20, and then is fixed to the reinforcing member 25. The reinforcing member 25 can be formed of a metal material, and the degree of warping thereof is smaller than that of the circuit board 20. If the cantilever-type adapter 21 is installed on the reinforcing member 25 (in this embodiment, the fixing portion 210A of the cantilever-type adapter 21 is connected to the cantilever-type adapter 21), the flatness will be better than when the cantilever-type adapter 21 is installed on the circuit board 20. With this configuration, the vertical probe head 22 is less susceptible to the effect of the warping of the circuit board 20 after replacement, and the vertical probe head 22 cannot be electrically connected stably to the cantilever-type adapter 21.

[0044] Please refer to Fig. 5. Fig. 5 is a flow chart of one embodiment of a design method of the probe card of the present invention. In this embodiment, design method 3 refers to design adjustment of the coupling capacitance in the cantilever type adapter.

[0045] In this embodiment, the probe card 2 includes a circuit board 20, a cantilever type adapter 21, and a vertical probe head 22, the cantilever type adapter 21 is electrically connected to the circuit board 20, the vertical probe head 22 is electrically connected to the cantilever type adapter 21, and the cantilever type adapter 21 has a mounting base 210 and a plurality of cantilever type adapter needles 211. The structure of the probe card is the same as that described above, so it will not be described again here. The plurality of cantilever type adapter needles 211 include two mutually adjacent first adapter needles 211A and second adapter needles 211B.

[0046] The step of the needle head design method 3 is to adjust the actual coupling capacitance between the first adapter needle 211A and the second adapter needle 211B based on the distance between the needle tips of the first adapter needle 211A and the second adapter needle 211B under the condition that the distance between one end of the first adapter needle 211A and the second adapter needle 211B is fixed, so as to conform to the threshold value of the coupling capacitance. Note that one end of the first adapter needle 211A and the second adapter needle 211B corresponds to the position of the needle tail of the vertical probe 24, and one end of the first adapter needle 211A and the second adapter needle 211B can be regarded as the needle head end, for example, as shown in FIG. 2A, the needle head refers to the distance from the tip 211k of the contact part 211g, and the distance usually corresponds to the pitch of the contact of the test object, therefore, the size does not have a specific limit and can be determined according to the actual test requirements. The threshold value of the coupling capacitance is determined according to the detection requirements and test conditions, and usually the client provides the test requirements and conditions to the probe card manufacturer.

[0047] In one embodiment, the adjustment method adjusts the relative distance between the fixed portion 211a of the first adapter needle 211A and the fixed portion 211a of the second adapter needle 211B, and adjusts the actual coupling capacitance between the first adapter needle 211A and the second adapter needle 211B. For example, in one embodiment, as shown in FIG. 2A, the corresponding shortest distances of the needle entry portions 211b of the first adapter needle 211A and the second adapter needle 211B are gradually decreased from the position where they enter the side edge 2110 of the fixed portion 210A, and the head region 211e of the two needle entry portions 211b has a head shortest distance d, and the tail region 211f has a tail shortest distance D, and the tail shortest distance D is greater than the head shortest distance d, but is not limited thereto, for example, the method of FIG. 2B may change the coupling capacitance value.

[0048] After determining the relative positions between the adapter needles to meet the threshold value of the coupling capacitance, the fixing part 210A is formed, and the fixing portion 211a for fixing the first adapter needle 211A and the second adapter needle 211B is further formed.

[0049] As shown in FIG. 6, this is an explanatory diagram of one embodiment of the test system of the present invention. In this embodiment, the test system 4 includes a mounting table 40 and a probe card 2. The mounting table 40 is used to transport a DUT (i.e., a wafer). The DUT has a pad 900. The probe card 2 contacts the pad 900 of the DUT via the vertical probe 24 and electrically connects to the DUT to perform an electrical test. The structure of the probe card 2 is as described above, so a detailed description will be omitted here.

[0050] 7 is a flow chart of an embodiment of the test method of the present invention. The test system shown in FIG. 6 performs an electrical test on the DUT under test. As shown in FIG. 6, in the method 5, step 50 includes providing the test system 4 shown in FIG. 6, which has a probe card 2 therein, the structure of which is as described above and will not be described again here. Next, step 51 is performed to bring the needle heads 242 of the multiple vertical probes 24 into contact with multiple pads 900 of the DUT under test. Next, in step 52, a test signal is transmitted to the DUT under test via the probe card 2 to test the DUT under test. [Explanation of symbols]

[0051] 2 Probe Card 20 Circuit Board 200 Top 201 Bottom surface 203 First Via 21 Cantilever type adapter 210 Mounting base 210A Fixed part 210B Base 2110 Side 210a top side 210b 1st through hole 210d bottom surface 211 Cantilever type adapter needle 211a Fixed part 211b Needle entry part 211c Exposed part 211d Contact 211g contact area 211h Contact Pad 212 Gap 22 Vertical probe head 23 Probe holder 230 Upper guide plate unit 230a Upper guide plate 230b Upper guide hole 230c top surface 230d bottom surface 231 Lower guide plate unit 231a Lower guide plate 231b Lower guide hole 231c top surface 231d Bottom surface 24 Vertical Probe 240 Needle tail 241 Needle body 242 Needle head 25 Reinforcement members 250 through hole 26a Leakage current prevention contact 26b Leakage current prevention contact 27 Coaxial Cable 3 ways 30 steps 31 process 32 processes 33 processes 4 Test System 40 Placement table 5 ways 50 steps 51 process 52 processes 90 Viewing direction CA1 Circuit board center axis CA2 1st center axis CA3 2nd center axis OP Overflow Area d1 Distance d2 distance DUT Object

Claims

1. A probe card suitable for performing a wafer acceptance test, the probe card comprising: A circuit board; a cantilever adapter electrically connected to the circuit board; a vertical probe head electrically connected to the cantilever-type adapter; Including, The vertical probe head includes: a probe holder including an upper guide plate unit and a lower guide plate unit, the upper guide plate unit having at least one upper guide plate and an upper guide hole penetrating the at least one upper guide plate, the lower guide plate unit having at least one lower guide plate and a lower guide hole penetrating the at least one lower guide plate, the upper guide plate unit and the lower guide plate unit each having an upper surface and a lower surface, and an accommodation space being formed between the lower surface of the upper guide plate unit and the upper surface of the lower guide plate unit; a vertical probe including a needle tail, a needle body and a needle head, the needle tail being provided with at least one upper guide hole, the needle body being located in the receiving space, and the needle head being provided with at least the lower guide hole; Including, a cantilever type adapter needle having a mounting base and a cantilever type adapter needle, the cantilever type adapter needle having a fixed portion and an exposed portion, the fixed portion being fixed to the mounting base, the exposed portion being located outside the mounting base, and the fixed portion entering from a side edge of the mounting base and forming a contact on a bottom surface of the mounting base.

2. 2. The probe card of claim 1, wherein the cantilever type adapter has a first adapter needle and a second adapter needle, the first adapter needle is adjacent to the second adapter needle and does not contact each other, the fixed portions of the first adapter needle and the second adapter needle have needle entry portions entering from a side edge of the fixed portion, the needle entry portions of the cantilever type adapter further include a head region away from the side edge of the fixed portion and a tail region adjacent to the fixed portion, the needle entry portions of the first adapter needle and the second adapter needle have a head minimum distance at corresponding positions of the two needle entry portions, and the tail regions of the needle entry portions of the first adapter needle and the second adapter needle have a tail minimum distance, the tail minimum distance being greater than the head minimum distance.

3. 3. The probe card according to claim 2, wherein the shortest distance between the positions where the needle entry portions of the first adapter needle and the second adapter needle correspond to each other gradually decreases from a position where the needle entry portions enter a side edge of the fixing portion.

4. 2. The probe card of claim 1, wherein the cantilever type adapter is installed on the circuit board, the mounting base includes a base and a fixing portion, the base includes an upper surface facing the circuit board and a first through hole, and the fixing portion is installed in the first through hole and extends to the upper surface of the base.

5. The probe card of claim 1, wherein the circuit board further includes a plurality of leakage current prevention contacts, each of the plurality of leakage current prevention contacts being attached to a bottom plate, the bottom plate being attached to the circuit board via an adhesive material, and the leakage current prevention contacts further include a signal circuit pattern surrounded by a protective circuit pattern.

6. The probe card of claim 5 , further comprising a plurality of coaxial cables each electrically connected to the leakage current prevention contact.

7. The probe card of claim 6 , wherein the circuit board further comprises a plurality of vias for passing the coaxial cable or the cantilever adapter needle.

8. 6. The probe card of claim 5, wherein the leakage current prevention contacts include a plurality of first leakage current prevention contacts on the upper surface of the circuit board and a plurality of second leakage current prevention contacts on the circuit board, both ends of each of the coaxial cables are electrically connected to the first leakage current prevention contacts and the second leakage current prevention contacts, respectively, the circuit board has a circuit board central axis along a thickness direction, the first leakage current prevention contacts have a first central axis in the thickness direction, and the second leakage current prevention contacts have a second central axis in the thickness direction, and a radial distance between the first central axis and the circuit board central axis is greater than a distance between the second central axis and the circuit board central axis.

9. The probe card of claim 1 , further comprising a reinforcing member removably mounted on the circuit board, the mounting base being connected to the reinforcing member.

10. The probe card according to claim 9 , wherein the reinforcing member is fixed to the circuit board by a fixing member.

11. 10. The probe card of claim 9, wherein the mounting base includes a base, the base including an upper surface facing the circuit board and a first through hole, the reinforcing member having a second through hole corresponding to the first through hole, the fixing portion being installed in the first through hole and the second through hole and extending to an upper surface of the base, and a gap is provided between the base and the circuit board to allow an exposed portion of the cantilever-type adapter to pass therethrough.

12. 2. The probe card according to claim 1, wherein the material of the cantilever-type adapter needle is one of beryllium, copper, rhenium, tungsten, gold, and silver, or an alloy of a combination thereof.

13. 2. The probe card of claim 1, wherein the contact of each cantilever-type adapter needle is an end of a needle body of the fixed portion, or the contact of each cantilever-type adapter needle is a contact pad coupled to the end of a needle body of the fixed portion.

14. The probe card of claim 1 , wherein the fixed portion is tapered.

15. 2. The probe card of claim 1, wherein the hardness of the cantilever type adapter needle is greater than 245 MPa and the resistance of the cantilever type adapter needle is less than 200 mΩ.

16. A method for designing a probe card, the probe card comprising: a circuit board, a cantilever type adapter, and a vertical probe head, the cantilever type adapter being electrically connected to the circuit board, the vertical probe head being electrically connected to the cantilever type adapter, the cantilever type adapter having a mounting base and a plurality of cantilever type adapter needles, the plurality of cantilever type adapter needles including two mutually adjacent first and second adapter needles; The method for designing the probe card includes: A method for designing a probe card, comprising: adjusting an actual coupling capacitance between the first adapter needle and the second adapter needle based on a distance between the first adapter needle and one end of the second adapter needle, under a condition in which the distance between the first adapter needle and one end of the second adapter needle is fixed, to satisfy a coupling capacitance threshold.

17. The mounting base of the cantilever adapter has a fixed portion, and each of the cantilever adapter needles in turn has a fixed portion and an exposed portion, the fixed portion is fixed to the fixed portion of the mounting base, and the exposed portion is outside the fixed portion, and the exposed portion is used for electrical connection to the circuit board, and the step of adjusting the actual coupling capacitance between the first adapter needle and the second adapter needle comprises:

17. The method of designing a probe card of claim 16, further comprising adjusting a relative distance between fixed portions of the first adapter needle and the second adapter needle to adjust an actual coupling capacitance between the first adapter needle and the second adapter needle.

18. The fixed portion enters from a side edge of the fixed portion, and contacts are formed on the bottom surface of the fixed portion of the mounting base, and each of the contacts is used to electrically contact the needle tail of each of the vertical probes, the fixed portions of the first adapter needle and the second adapter needle have needle entry portions that enter from the side edges of the fixed portions, and the process of adjusting the relative distance between the fixed portions of the first adapter needle and the second adapter needle comprises: The method for designing a probe card according to claim 17, further comprising adjusting the shortest distance between the positions where the needle entry portions of the first adapter needle and the second adapter needle correspond to each other so as to gradually decrease from the position where they enter the side edge of the fixed portion.

19. Providing a probe card according to claim 1; a step of contacting needle heads of the vertical probes of the plurality of probe cards with a plurality of conductive contacts of the test object; transmitting a test signal to a test subject via the probe card; 4. A test method, comprising:

20. a placement table on which a subject is placed; the probe card according to claim 1 , wherein the probe card and the test object are electrically connected to each other by contacting a vertical probe of the probe card with the test object; 23. A test system comprising:

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