Probe card and design method thereof, and method and system for testing object to be tested through probe card

Abstract

The invention provides a probe card, a design method thereof, and a method and a system for testing an object to be tested through the probe card. The probe card comprises a circuit board, a cantilever type switching converter electrically connected with the circuit board, and a vertical probe head electrically connected with the cantilever type switching converter. The vertical probe head comprises a probe seat and a plurality of vertical probes. The cantilever type switching converter is provided with a mounting seat and a plurality of cantilever type switching pins, and each cantilever type switching pin is provided with a fixed section and an exposed section. The fixed section is fixed on the mounting seat, the exposed section is positioned outside the mounting seat, and the fixed section enters from the side edge of the mounting seat and forms a contact on the bottom surface of the mounting seat.

Description

Technical Field

[0001] The invention relates to a probe card, a probe card design method, and a test method and a test system using the probe card. Background Art

[0002] Wafer Acceptance Test (WAT) is a test method used for wafer front-end process inspection. It is an important step in the semiconductor manufacturing process. It is mainly used to ensure the quality and performance of the object to be tested (i.e. wafer) to ensure that potential problems are discovered early before the wafer enters the subsequent process (such as cutting, packaging, etc.), thereby reducing costs and improving product quality. Wafer acceptance test mainly tests the contacts placed on the wafer scribe line. The test method is to use the probe of the probe card to contact the contacts of the wafer scribe line, and the other end of the probe card is connected to the test instrument of the wafer acceptance test system to measure the wafer.

[0003] With the advancement of semiconductor manufacturing processes, the size of chips is getting smaller and smaller, and the pad size and pad pitch of the chip are both miniaturized. As a result, when the cantilever probe of the traditional cantilever probe card (CPC) contacts the electrical contacts on the chip under the wafer, the probe tip will move horizontally due to the vertical relative movement between the probe tip and the wafer, and exceed the area of ​​the electrical contacts, thereby failing to effectively contact the electrical contacts. Summary of the invention

[0004] The object of the present invention is to provide a probe card and a design method thereof, as well as a method and system for testing an object to be tested via a probe card, combining the cantilever probe of a cantilever probe card with a vertical probe head to effectively and stably test the object to be tested, thereby solving the problem that traditional cantilever probe cards cannot effectively perform electrical tests due to the miniaturization of electrical contact size and spacing.

[0005] Therefore, the present invention provides a probe card suitable for performing a wafer acceptance test on a wafer. The probe card includes: a circuit board; a cantilever adapter converter electrically connected to the circuit board; and a vertical probe head electrically connected to the cantilever adapter converter. The vertical probe head includes a probe seat and a vertical probe. The probe seat 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 passing through the upper guide plate. The lower guide plate unit has a lower guide plate and a lower guide hole passing through the lower guide plate. The upper guide plate unit and the lower guide plate unit have an upper surface and a lower surface respectively. An accommodating 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, a needle body and a needle head. The needle tail is provided with an upper guide hole, the needle body is located in the accommodating space, and the needle head is provided with a lower guide hole. The cantilever transfer converter has a mounting seat and a cantilever transfer pin, the cantilever transfer pin has a fixed section and an exposed section, the fixed section is fixed to the mounting seat, the exposed section is located outside the mounting seat, the fixed section enters from the side of the mounting seat and forms a contact point on the bottom surface of the mounting seat.

[0006] In addition, if the distance between adjacent cantilever adapter pins is not properly adjusted, coupling capacitance is easily generated, which in turn affects the results of electrical testing. Therefore, the configuration of adjacent cantilever adapter pins needs to be adjusted to reduce the coupling capacitance value of adjacent cantilever adapter pins, thereby reducing the energy storage effect between the probes, and further improving the stability of the leakage current test.

[0007] Therefore, in one embodiment, the cantilever transfer needle has a first transfer needle and a second transfer needle, the first transfer needle and the second transfer needle are adjacent to each other and do not contact each other, the fixed sections of the first transfer needle and the second transfer needle have a needle entry section that enters from the side of the fixed portion of the mounting seat, and the needle entry section of each cantilever transfer needle further includes a head section away from the side of the fixed portion and a tail section adjacent to the side of the fixed portion, in the head section of the needle entry section of the first transfer needle and the second transfer needle, the corresponding positions of the two needle entry sections have the shortest distance of the head, and the tail section of the needle entry section of the first transfer needle and the second transfer needle has the shortest distance of the tail, and the shortest distance of the tail is greater than the shortest distance of the head. In another embodiment, the shortest distance of the corresponding positions of the needle entry sections of the first transfer needle and the second transfer needle gradually decreases from the position entering the side of the fixed portion.

[0008] In addition, in order to avoid the problem of unstable contact caused by the cantilever adapter needle's needle tip shaking due to contact force causing the needle tip position to shift when the cantilever adapter needle makes electrical contact with the vertical probe of the vertical probe head, in one embodiment, the cantilever adapter converter is disposed on the circuit board, and the mounting base includes a base, which includes an upper surface facing the circuit board and a first through hole, and the fixing portion is disposed in the first through hole and extends to the upper surface of the base, and the fixing portion covers the fixing section.

[0009] In addition, in order to ensure that the structure of the probe card itself is suitable for leakage current testing, an electrical contact ring (pad ring) is provided on the lower surface of the circuit board for welding cantilever transfer pins to ensure that when there is leakage current, it can be guided to the ground by the protection circuit pattern (guard), and no leakage current will flow to other electrical contact rings to ensure that the leakage current is within the specification. In one embodiment, the circuit board further includes a plurality of anti-leakage current contacts, wherein each of the plurality of anti-leakage current contacts is provided on a base plate, and the base plate is provided on the circuit board through a bonding material, and the anti-leakage current contact further includes a signal circuit pattern, and the outer periphery of the signal circuit pattern is surrounded by a protection circuit pattern. If the anti-leakage current contact does not meet the leakage current test specification, the base plate can be removed and replaced with a new base plate with anti-leakage current contacts, which can overcome the remedial mechanism that the contact part does not meet the leakage current test specification.

[0010] In addition, the flatness of the reinforcement is smaller than the flatness of the circuit board. When the mounting seat is set on the reinforcement, the bottom surface of the fixing portion of the mounting seat has a first flatness. When the mounting seat is set on the circuit board, the bottom surface of the fixing portion of the mounting seat has a second flatness. The first flatness is smaller than the second flatness. When the probe card with the mounting seat set on the circuit board is used to replace the vertical probe head, the vertical probe of the vertical probe head may not be able to stably electrically connect to the cantilever adapter converter due to the poor second flatness of the bottom surface of the fixing portion, resulting in poor stability of the wafer acceptance test. When the probe card with the mounting seat set on the reinforcement is used to replace the vertical probe head, the first flatness of the bottom surface of the fixing portion is better, which can make the vertical probe of the vertical probe head stably electrically connect to the cantilever adapter converter, further improving the stability of the wafer acceptance test.

[0011] In one embodiment, the material of each cantilever transfer pin is an alloy of one or a combination of beryllium, copper, rhenium, tungsten, gold and silver.

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

[0013] In one embodiment, the fixing section is cone-shaped.

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

[0015] In addition, when the wafer acceptance test is performed by the probe card of the present invention, the shaking caused by the test environment is avoided to affect the shaking of the cantilever transfer needle. The hardness of the cantilever transfer needle is greater than 245Mpa, which can avoid the shaking of the cantilever transfer needle and cause instability in the test results. The leakage current between two adjacent cantilever transfer needles needs to be avoided, that is, one of the cantilever transfer needles has current flowing to the other cantilever transfer needle. The resistance of the cantilever transfer needle is less than 200mΩ, which can avoid the leakage current between adjacent cantilever transfer needles to the greatest extent.

[0016] In order to solve the problem of coupling capacitance interference between adjacent cantilever transfer pins and improve the accuracy of electrical measurement, the influence of coupling capacitance is reduced by adjusting the distance (gap) between the cantilever transfer pins. In one embodiment, the present invention provides a probe card design method, the probe card includes a circuit board, a cantilever transfer converter and a vertical probe head, the cantilever transfer converter is electrically connected to the circuit board, the vertical probe head is electrically connected to the cantilever transfer converter, the cantilever transfer converter has a mounting seat and a plurality of cantilever transfer pins, the plurality of cantilever transfer pins include two adjacent first transfer pins and a second transfer pin, the probe card design method includes: according to the spacing between one end of the first transfer pin and the second transfer pin, under the condition of fixing the spacing between one end of the first transfer pin and the second transfer pin, adjusting the actual coupling capacitance between the first transfer pin and the second transfer pin to meet the coupling capacitance threshold. In another embodiment, the mounting base of the cantilever adapter converter has a fixed portion, and each cantilever adapter pin has a fixed section and an exposed section in sequence, the fixed section is fixed to the fixed portion of the mounting base, and the exposed section is outside the fixed portion, and the exposed section is used to electrically connect to the circuit board, wherein the step of adjusting the actual coupling capacitance between the first adapter pin and the second adapter pin includes: adjusting the relative distance between the fixed sections of the first adapter pin and the second adapter pin to adjust the actual coupling capacitance between the first adapter pin and the second adapter pin.

[0017] The present invention further provides a testing method, comprising the following steps: providing the aforementioned probe card, then making the needles of the vertical probes of the probe card contact the multiple conductive contacts of the object to be tested correspondingly, and finally transmitting the test signal to the object to be tested through the probe card.

[0018] The present invention provides a testing system, which includes a carrier and a probe card. The carrier carries a test object. The probe card contacts the test object via vertical probes of the probe card so that the probe card and the test object are electrically connected. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1A FIG. 4 is an exploded view of the first embodiment of the probe card of the present invention.

[0020] Figure 1B and Figure 1C3D images of the probe card according to the first embodiment of the present invention observed from different viewing angles.

[0021] Figure 1D and Figure 1E for Figure 1B Cross-sectional view of .

[0022] Figure 1F FIG. 4 is a cross-sectional view of a second embodiment of the probe card of the present invention.

[0023] Figure 2A FIG. 4 is a schematic diagram of a probe card according to a third embodiment of the present invention.

[0024] Figure 2B FIG. 4 is a schematic diagram of a probe card according to a fourth embodiment of the present invention.

[0025] Figure 3A FIG. 4 is a bottom view of the first embodiment of the probe card of the present invention.

[0026] Figure 3B FIG. 4 is a schematic diagram of an embodiment of an anti-leakage current contact of a probe card of the present invention.

[0027] Figure 4A FIG. 5 is a schematic diagram of a probe card according to a fifth embodiment of the present invention.

[0028] Figure 4B FIG. 4 is a schematic diagram of a sixth embodiment of a probe card according to the present invention.

[0029] Figure 5 The flowchart of one embodiment of the probe card design method of the present invention.

[0030] Figure 6 FIG. 4 is a schematic diagram of an embodiment of a testing system of the present invention.

[0031] Figure 7 The figure is a flow chart of an embodiment of a method for testing a semiconductor wafer via a probe card according to the present invention.

[0032] Explanation of reference numerals: 2-probe card; 20-circuit board; 200-upper surface; 201-lower surface; 203-first through hole; 21-cantilever adapter converter; 210-mounting seat; 210A-fixing portion; 210B-base; 2110-side; 210a-upper surface; 210b-first through hole; 210d-lower surface; 211-cantilever adapter needle; 211a-fixing section; 211b-needle entry section; 211c-exposed section; 211d-contact point; 211g-contact section; 211h-contact contact point; 212-gap; 22-vertical probe head; 23-probe seat; 230-upper guide plate unit; 230a-upper guide plate; 230b-upper guide hole; 230c -upper surface; 230d-lower surface; 231-lower guide plate unit; 231a-lower guide plate; 231b-lower guide hole; 231c-upper surface; 231d-lower surface; 24-vertical probe; 240-needle tail; 241-needle body; 242-needle head; 25-reinforcement; 250-through hole; 26a, 26b-anti-leakage current contacts; 27-coaxial line; 3-method; 30~33-steps; 4-test system; 40-carrying platform; 5-method; 50~52-steps; 90-viewing angle; CA1-central axis of circuit board; CA2-first central axis; CA3-second central axis; CA-central area; OP-overflow block; d1, d2-distance; DUT-object under test. DETAILED DESCRIPTION

[0033] Various exemplary embodiments are provided below to make the disclosure of the present invention more detailed and complete; however, the various exemplary embodiments are not intended to limit the present invention.

[0034] Please also see Figures 1A to 1E . Figure 1A FIG. 2 is an exploded view of the first embodiment of the probe card 2 of the present invention. Figure 1B and Figure 1C 3D images of the first embodiment of the probe card 2 of the present invention observed from different viewing angles, wherein: Figure 1B is a three-dimensional image of the probe card 2 viewed from an oblique upper perspective, Figure 1C It is a three-dimensional view of the probe card 2 viewed from an oblique downward angle. Figure 1D and Figure 1E for Figure 1B Specifically, when the probe card 2 is Figure 1A Generally, the circuit board 20 is placed parallel to the ground and all components are assembled. The cross-sectional view is cut longitudinally from one end point on the outer circumference of the disc-shaped circuit board 20 to the other end point on the outer circumference of the circuit board 20. The distance between the two end points is the diameter of the outer circumference of the circuit board 20, where Figure 1D The cross-sectional view of FIG. 2 clearly shows the detailed structure of the circuit board 20, the reinforcing member 25, the cantilever type transfer converter 21 and the positional relationship between the components. Figure 1E The cross-sectional view of FIG. 2 shows the detailed structure of the vertical probe head 22 more clearly.

[0035] The probe card 2 includes a circuit board 20 , a cantilever transfer converter 21 , and a vertical probe head 22 . The cantilever transfer converter 21 is electrically connected to the circuit board 20 . The vertical probe head 22 is electrically connected to the cantilever transfer converter 21 .

[0036] 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 through hole 203. The first through hole 203 is formed between the upper surface 200 and the lower surface 201 and penetrates the circuit board 20. The leakage current prevention contact 26a is disposed on the upper surface 200, and the leakage current prevention contact 26b is disposed 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 is electrically connected to the leakage current prevention contact 26b. The coaxial cable 27 passes through the circuit board 20 via the first through hole 203.

[0037] One of the purposes of using the anti-leakage current contacts 26a, 26b in this embodiment is to prevent current leakage. Specifically, before the wafer acceptance test is performed on the probe card 2, a leakage current test may be performed to confirm that the leakage current of the probe card meets the standard specification. Otherwise, when the wafer acceptance test is performed, the leakage current of the probe card may cause damage to the wafer. For example, the standard specification may be that the leakage current is less than 1pA (1x10 -12 A). 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.

[0038] One of the purposes of using the coaxial line 27 in this embodiment is to be applicable to high frequency testing. In other possible embodiments, the circuit board 20 may use other types of cables, not limited to the coaxial line 27, but may not be applicable to high frequency testing.

[0039] The cantilever adapter converter 21 includes a mounting base 210 and a cantilever adapter pin 211. In some embodiments of the present invention, the material of the cantilever adapter pin 211 is an alloy of one or a combination of beryllium, copper, rhenium, tungsten, gold and silver. In addition, in some embodiments of the present invention, the hardness of the cantilever adapter pin 211 is greater than 245Mpa, and the resistance of the cantilever adapter pin 211 is less than 200mΩ.

[0040] In the present embodiment, the mounting seat 210 includes a fixing portion 210A and a base 210B. The material of the fixing portion 210A is a fixing structure formed by a polymer material (e.g., epoxy resin). The base 210B is an annular structure, and the hollow area CA surrounded by it is defined as a first through hole 210b, and the epoxy resin is filled in the first through hole 210b. The probe card of the present embodiment further includes a reinforcement member 25, which is detachably disposed in the through hole 202 of the circuit board 20. The reinforcement member 25 mounting seat 210 is connected to the reinforcement member 25 and has a through hole 250, and its outer wall is penetrated in the through hole 202 of the circuit board 20. The fixing portion 210A is also filled in the through hole 202, and a portion of the epoxy resin overflows from the gap between the upper surface of the base 210B and the reinforcement member 25 to form an overflow block OP.

[0041] It is worth noting that a person skilled in the art with general knowledge in the technical field to which the present invention belongs may appropriately change the structure of the mounting base 210 of the present embodiment, and may also choose not to use the reinforcement 25, or change the structure of the reinforcement 25 or the position relative to the mounting base, as long as the cantilever adapter pin 211 can be fixed and the circuit board 20 and the vertical probe head 22 can be stably electrically connected. For example, in other possible embodiments of the present invention, the reinforcement 25 of the probe card may be configured to be non-detachable. For another example, in other possible embodiments of the present invention, the probe card may not use the reinforcement 25, so that a gap is formed between the upper surface of the base 210B and the lower surface 201 of the circuit board 20, and a portion of the epoxy resin overflows from the gap to form an overflow block OP.

[0042] Compared with other possible embodiments of the present invention, this embodiment has at least the following advantages. First, a reinforcing member 25 is provided to increase the fixing effect between the mounting seat 210 and the circuit board 20, and to improve the stability of the electrical connection between the contact 211 of the mounting seat 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 the position configuration in the through hole 202 of the circuit board 20 produce a better fixing effect and improve the stability effect. Third, the reinforcing member 25 is detachable. Compared with other possible embodiments of the present invention, the corresponding cantilever adapter converter 21 and the reinforcing member 25 can be replaced on the same circuit board 20 according to different DUTs, saving material costs. Specifically, the mounting seat 210 of the cantilever adapter converter 21 is set on the reinforcing member 25, and the exposed section 211c of the cantilever adapter pin 211 is unsoldered from the anti-leakage current contact 26b, so that the reinforcing member 25 can be removed from the circuit board 20.

[0043] The cantilever transfer pin 211 has a fixed section 211a and an exposed section 211c in sequence, wherein the fixed section 211a is fixed to the fixed portion 210A of the mounting base 210, and the exposed section 211c is outside the fixed portion 210A and extends toward the circuit board 20, and the exposed section 211c is used to electrically connect the contact points of the circuit board 20. The fixed section 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 the bottom surface (or lower surface 210d) of the fixed portion 210A of the mounting base 210 forms a contact point 211d, and each contact point 211d is used to electrically contact the needle tail 240 of each vertical probe 24.

[0044] In the present embodiment, the fixing section 211a is in a cone shape, such as a circular cone or a pyramid structure. It should be noted that the fixing section 211a is not limited to having a cone structure. In other possible embodiments of the present invention, a person skilled in the art with common knowledge in the art to which the present invention belongs may use a thinner needle in response to the reduced pitch of the electrical contacts of the wafer, and the fixing section 211a may not necessarily have a cone structure. The fixing section 211a of the probe card of the present embodiment uses a cone structure. Compared with some other possible embodiments of the present invention, the fixing section 211a has a cone structure, which can adjust the size of the contact between the cantilever transfer needle 211 and the needle tail of the vertical probe 22 to achieve electrical contact stability.

[0045] In the present embodiment, the fixed section 211a is a probe with an angle structure, that is, the fixed section 211a includes a needle insertion section 211b and a contact section 211g connected to the needle insertion section 211b at an angle, and the contact section 211g can be regarded as the needle head of the cantilever adapter needle 211. However, the present invention is not limited to this. For example, in other possible embodiments of the present invention, the needle insertion section 211b is a needle body structure with a curvature, one end of which is bent and protrudes from the fixed portion 210A through the curvature to form a contact point that is in electrical contact with the needle tail 240 of each vertical probe 24. Compared with some other possible embodiments of the present invention, the angle structure of the present embodiment makes it easier to align the contact point 211d of the cantilever adapter needle 211 when the cantilever adapter needle 211 is installed on the mounting seat 210.

[0046] The vertical probe head 22 includes a probe base 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 the at least one upper guide plate. The lower guide plate unit 231 has at least one lower guide plate 231a and a plurality of lower guide holes 231b penetrating the at least one lower guide plate. The upper guide plate unit 230 has an upper surface 230c and a lower surface 230d. 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 240 , a needle body 241 and a needle head 242 . The needle tail 240 passes through an upper guide hole 230 b and is used to electrically contact the cantilever adapter 21 . The needle body 241 is located in the accommodating space S. The needle head 242 passes through a lower guide hole 231 b and is used to electrically contact the DUT.

[0047] In this embodiment, the vertical probe head 22 is disposed on the reinforcing member 25. Specifically, a locking element (such as a locking element 28) passes through the through hole 220 of the vertical probe head 22 and the through hole 2100 of the base 210B of the mounting seat 210, and then is locked in the locking hole 252 of the reinforcing member 25, or passes through the abutment ring 251 of the reinforcing member 25, and is locked by a nut and a locking element, so that the vertical probe head 22 is disposed on the reinforcing member 25. Therefore, the vertical probe head 22 and the mounting seat 210 are directly disposed on the reinforcing member 25, and the reference of the flatness datum of the vertical probe head 22 and the mounting seat 210 is determined by the reinforcing member 25. The flatness of the reinforcement 25 is smaller than the flatness of the circuit board 20. When the mounting base 210 is set on the reinforcement 25, the bottom surface 210d of the fixed portion 210A of the mounting base 210 has a first flatness. When the mounting base 210 is set on the circuit board 20, the bottom surface 210d of the fixed portion 210A of the mounting base 210 has a second flatness. The first flatness is smaller than the second flatness. When the mounting base 210 is set on the probe card of the circuit board 20 to replace the vertical probe head 22, the second flatness of the bottom surface 210d of the fixing portion may be poor, resulting in the vertical probe 24 of the vertical probe head 22 being unable to stably electrically connect to the cantilever adapter converter 21, resulting in poor stability of the wafer acceptance test. When the mounting base 210 is set on the probe card 2 of the reinforcement 25 to replace the vertical probe head 22, the first flatness of the bottom surface 210d of the fixing portion is better, so that the vertical probe 24 of the vertical probe head 22 can be stably electrically connected to the cantilever adapter converter 21, further improving the stability of the wafer acceptance test.

[0048] In this embodiment, the contact point 211d of each cantilever adapter pin 211 is the end of the fixed section 211a, and the lowest position of the end of the fixed section 211a is exactly aligned with the bottom surface (or lower surface 210d) plane of the fixed portion 210A of the mounting seat 210. In some other possible embodiments of the present invention, the lowest position of the end of the fixed section 211a can be located above or below the bottom surface (or lower surface 210d) plane of the fixed portion 210A of the mounting seat 210. In addition, in another embodiment, if Figure 1F As shown, the contact point 211d of the cantilever transfer pin 211 is an enlarged contact pad 211h, and the contact pad 211h is located below the bottom surface (or lower surface 210d) of the fixing 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 transfer pin 211 of the cantilever transfer converter 21 and the vertical probe 24 of the vertical probe head 22.

[0049] Please refer to Figure 2A . Figure 2A Schematic diagram of the third embodiment of the probe card of the present invention. In this embodiment, three cantilever transfer needles 211 are used as an example, however, the number of cantilever transfer needles 211 of the probe card of the present invention is not limited to three. The cantilever transfer needle 211 includes a first transfer needle 211A and a second transfer needle 211B, the first transfer needle 211A and the second transfer needle 211B are adjacent to each other and do not contact each other, and the fixing section 211a of the first transfer needle 211A and the second transfer needle 211B has a needle entry section 211b entered by the side 2110 of the fixing portion 210A. It should be noted that the side 2110 described in this embodiment is not limited to Figure 1D The side of the left needle entry shown is a limitation, such as Figure 3AAs shown, the side edge can be any position of the edge of the fixing portion 210A in 360 degrees. The needle insertion section 211b of the plurality of cantilever transfer needles 211 further includes a head section 211e away from the side edge 2110 of the fixing portion 210A and a tail section 211f adjacent to the side edge 2110 of the fixing portion. In the head section 211e of the needle insertion section 211b of the first transfer needle 211A and the second transfer needle 211B, the corresponding positions of the two needle insertion sections 211b have the shortest head distance d, and the tail section 211f of the needle insertion section 211b of the first transfer needle 211A and the second transfer needle 211B has the shortest tail distance D, which is greater than the shortest head distance d, and there is no specific restriction on the change of the probe distance between the shortest distance D and d. In this embodiment, the shortest distance D and d are gradually reduced, that is, the shortest distance between the corresponding positions of the needle sections 211b of the first transfer needle 211A and the second transfer needle 211B gradually decreases from the position of entering the side edge 2110 of the fixing portion to the shortest distance d of the head. By designing the two distances to be different, the coupling capacitance interference between the probes can be reduced, thereby improving the accuracy of electrical testing.

[0050] Please refer to Figure 2B . Figure 2B It is a schematic diagram of the third embodiment of the probe card of the present invention. In this embodiment, two cantilever transfer needles 211 are used as an example, but the number of cantilever transfer needles 211 of the probe card of the present invention is not limited to two. In this embodiment, the probe distance between the shortest distances D and d changes from the shortest distance D at the tail end to the shortest distance d at the head end, and after reaching the shortest distance d in the middle section, it remains parallel to the contact section 211g, so it is another implementation mode of reducing the coupling capacitance. In detail, in this embodiment, the plurality of cantilever transfer needles 211 have a first transfer needle 211A and a second transfer needle 211B, the first transfer needle 211A and the second transfer needle 211B are adjacent to each other and do not contact each other, and the first transfer needle 211A and the second transfer needle 211B respectively have a fixed section 211a and an exposed section 211c. The fixing section 211a includes a needle insertion section 211b and a contact section 211g, wherein the needle insertion section 211b further includes a head section 211e which is parallel to the side 2110 away from the fixing portion 210A and a tail section 211f which is adjacent to the side 2110 of the fixing portion and is not parallel to each other. The head section 211e of the needle insertion section 211b of the first transfer needle 211A and the second transfer needle 211B has a head shortest distance d at a position corresponding to the head section 211e, and the tail section 211f of the needle insertion section 211b of the first transfer needle 211A and the second transfer needle 211B has a tail shortest distance D, and the tail shortest distance D is greater than the head shortest distance d.

[0051] In addition, in order to ensure that the cantilever bending of the cantilever transfer needle 211 causes the contact section 211g of the probe to move laterally and cannot contact the needle tail 240 of the vertical probe 24 during measurement. In this embodiment, the cantilever transfer converter 21 is arranged on the circuit board 20, the base 210B of the mounting seat 210 includes an upper surface 210a facing the circuit board 20 and a first through hole 210b, and the fixing portion 210A is arranged in the first through hole 210b and extends to the upper surface 210a of the base 210B, and fills the gap 212 between the base 210B and the circuit board 20, so that the fixing section 211a can be covered by the fixing portion 210A, thereby keeping the contact section 211g in place. The gap 212 can also be used to allow the exposed section 211c of the cantilever transfer needle 211 to pass through and enter the fixing portion 210A.

[0052] Please refer to Figure 3A and Figure 3B . Figure 3A FIG. 1 is a bottom view of the first embodiment of the probe card of the present invention. Figure 3BThis is a schematic diagram of an embodiment of the anti-leakage current contact of the probe card of the present invention. In order to ensure that the probe card meets the leakage current test standard, an electrical contact ring (pad ring) is set on the lower surface 201 of the circuit board 20 for welding the cantilever transfer pin to ensure that when there is leakage current, it can be guided to the ground by the protection circuit pattern (guard), and no leakage current will flow to other electrical contact rings to ensure that the leakage is within the specification. In this embodiment, the upper surface 200 of the circuit board 20 has a plurality of anti-leakage current contacts 26a, and the lower surface 201 of the circuit board 20 has a plurality of anti-leakage current contacts 26b. Each anti-leakage current contact 26a, 26b is set on the circuit board 20 via a base plate 260 to form an anti-leakage current structure. In this embodiment, each anti-leakage current contact 26a, 26b further includes a signal circuit pattern 261, which is surrounded by a protection circuit pattern 262. Among them, a conductive layer 263 and an insulating layer 264 formed on the conductive layer 263 are further included between the bottom plate 260 and the signal line pattern 261. The protection line pattern 262 is electrically connected to the conductive layer 263. The conductive layer 263 provides a vertical shielding function for the signal line pattern 261 below the insulating layer 264. The bottom plate 260 is further arranged on the surface of the circuit board 20. It should be noted that the conductive layer 263 and the insulating layer 264 can be determined according to the use requirements and there is no certain restriction. The bottom plate 260 is arranged on the circuit board 20 by bonding materials. If the anti-leakage current contact does not meet the leakage current test specification, the bottom plate 260 can be removed and replaced with a new bottom plate 260 with anti-leakage current contacts 26a, 26b, which can overcome the remedial mechanism that the contact part does not meet the leakage current test specification. It should be noted that the anti-leakage current contacts 26a, 26b can be a combination of a signal circuit pattern 261 and a protection circuit pattern 262 set on a base plate, or a plurality of signal circuit patterns 261 and protection circuit patterns 262 are arranged at intervals and set on a base plate at the same time. There is no specific limitation and it can be determined according to actual test requirements.

[0053] Please also see Figure 1D and Figure 3A and Figure 3B In this embodiment, the circuit board 20 has a circuit board center axis CA1 along its thickness direction, the first anti-leakage current contact 26a has a first center axis CA2 along its thickness direction, and the second anti-leakage current contact 26b has a second center axis CA3 along its thickness direction, wherein the radial distance d1 between the first center axis CA2 and the circuit board center axis CA1 is greater than the distance d2 between the second center axis CA3 and the circuit board center axis CA1. The coaxial line 27 includes an axial core wire and an insulating layer and an outer conductor layer coaxially surrounding the core wire, the two ends of the core wire of the coaxial line 27 are respectively electrically connected to the signal line pattern 261 of the anti-leakage current contacts 26a, 26b, and the two ends of the outer conductor layer of the coaxial line 27 are respectively electrically connected to the protection line pattern 262 of the anti-leakage current contacts 26a, 26b.

[0054] It should be noted that the arrangement of the leakage current preventing contacts 26a, 26b is not limited to the first embodiment. Figure 4A . Figure 4A Schematic diagram of the fifth embodiment of the probe card of the present invention. The fifth embodiment is basically similar to the first embodiment, except that the anti-leakage current contacts 26a, 26b are both disposed on the upper surface 200 of the circuit board 20. The circuit board 20 further includes a plurality of second through holes 204 for the cantilever adapter pin 211 to pass through. In the present embodiment, the exposed section 211c of the cantilever adapter pin 211 further includes a first needle section 211i and a second needle section 211j, wherein the first needle section 211i is connected to the fixed section 211a, and the second needle section 211j is connected to the first needle section 211i, and has an angle θ. The second needle section 211j further passes through the second through hole 204 and is electrically connected to the anti-leakage current contact 26b disposed on the upper surface 200. The anti-leakage current contact 26b is then electrically connected to the anti-leakage current contact 26a through the coaxial line 27. The plurality of leakage-proof current contacts 26a, 26b include a plurality of first leakage-proof current contacts 26a on the upper surface 200 of the circuit board 20, and a plurality of second leakage-proof current contacts 26b on the upper surface 201 of the circuit board 20, and each coaxial line 27 is electrically connected at both ends to the first leakage-proof current contact 26a and the second leakage-proof current contact 26b, respectively. The center of the circuit board 20 has a circuit board center axis CA1 along its thickness direction, the first leakage-proof current contact 26a has a first center axis CA2 along its thickness direction, and the second leakage-proof current contact 26b has a second center axis CA3 along its thickness direction, wherein a radial distance d1 between the first center axis CA2 and the circuit board center axis CA1 is greater than a distance d2 between the second center axis CA3 and the circuit board center axis CA1.

[0055] Please refer to Figure 4B . Figure 4BSchematic diagram of the sixth embodiment of the probe card of the present invention. The sixth embodiment is basically similar to the first embodiment, except that in this embodiment, the circuit board 20 further has a locking hole 205, which can be a through hole or a blind hole. The locking element 28 passes through the reinforcing member 25 and abuts against the abutting ring 251 of the upper surface 200 of the circuit board 20, and then is locked in the locking hole 205. In addition, the locking method of the locking element 28 is not necessarily limited to this. In another embodiment, the locking element 28 passes through the circuit board 20 and abuts against the lower surface 201 of the circuit board 20, and then is locked on the reinforcing member 25. It should be noted that the reinforcing member 25 can be made of metal material, and its warpage is smaller than the warpage of the circuit board 20. If the cantilever adapter converter 21 is arranged on the reinforcing member 25 (in this embodiment, the fixing portion 210A of the cantilever adapter converter 21 is connected to the cantilever adapter converter 21), the flatness will be better than that of the cantilever adapter converter 21 being arranged on the circuit board 20. With this structure, after the vertical probe head 22 is replaced, it is less likely to be affected by the warping of the circuit board 20 , which may cause the vertical probe head 22 to be unable to stably electrically connect to the cantilever adapter converter 21 .

[0056] See also Figure 5 . Figure 5 The flowchart of one embodiment of the probe card design method of the present invention is shown in FIG.

[0057] In this embodiment, the probe card 2 includes a circuit board 20, a cantilever transfer converter 21 and a vertical probe head 22, wherein the cantilever transfer converter 21 is electrically connected to the circuit board 20, and the vertical probe head 22 is electrically connected to the cantilever transfer converter 21, and the cantilever transfer converter 21 has a mounting seat 210 and a plurality of cantilever transfer pins 211. The structure of the probe card is the same as described above and will not be described in detail here. The plurality of cantilever transfer pins 211 include two adjacent first transfer pins 211A and a second transfer pin 211B.

[0058] The steps of design method 3 are to adjust the actual coupling capacitance between the first transfer pin 211A and the second transfer pin 211B according to the distance between the needle ends of the first transfer pin 211A and the second transfer pin 211B, so as to meet the coupling capacitance threshold value under the condition of fixing the distance between the first transfer pin 211A and the second transfer pin 211B. It should be noted that one end of the first transfer pin 211A and the second transfer pin 211B corresponds to the needle tail position of the vertical probe 24, and one end of the first transfer pin 211A and the second transfer pin 211B can be regarded as the needle end, for example, Figure 2AAs shown, the distance between the tip 211k of the needle finger contact section 211g is usually the distance between the contact points of the object to be tested. Therefore, there is no specific limit to its size and it can be determined according to actual test requirements. The coupling capacitance threshold is determined according to the detection requirements and test conditions, which are usually the test requirements and conditions provided by the client to the probe card manufacturer.

[0059] In one embodiment, the adjustment method is to adjust the relative distance between the fixing sections 211a of the first transfer pin 211A and the second transfer pin 211B to adjust the actual coupling capacitance between the first transfer pin 211A and the second transfer pin 211B. Figure 2A As shown, the shortest distances of the corresponding positions of the needle sections 211b of the first transfer needle 211A and the second transfer needle 211B are adjusted to gradually decrease from the position of the side 2110 entering the fixing portion 210A, so that the head section 211e of the two needle sections 211b has the shortest head distance d, and the tail section 211f has the shortest tail distance D, and the shortest tail distance D is greater than the shortest head distance d, but this is not limited to, for example: Figure 2B The coupling capacitor value can also be changed in this way.

[0060] After the relative positions between the transfer pins are determined to meet the coupling capacitance threshold, a fixing portion 210A is further formed to fix the fixing segments 211 a of the first transfer pin 211A and the second transfer pin 211B.

[0061] like Figure 6 As shown, it is a schematic diagram of an embodiment of the test system of the present invention. In this embodiment, the test system 4 includes a carrier 40 and a probe card 2. The carrier 40 is used to carry the object under test DUT (i.e., wafer). The object under test DUT has an electrical contact 900. The probe card 2 contacts the electrical contact 900 of the object under test DUT via a vertical probe 24 to electrically connect with the object under test DUT to perform an electrical test. The structure of the probe card 2 is as described above and will not be repeated here.

[0062] See also Figure 7 FIG. 1 is a flow chart of an embodiment of the testing method of the present invention. Figure 6 The test system shown in the figure performs electrical testing on the DUT. Method 5 includes step 50 providing Figure 6 The test system 4 shown has a probe card 2 therein, and its structure is as described above and will not be described in detail here. Then, step 51 is performed to make the needles 242 of the plurality of vertical probes 24 contact the plurality of conductive contacts 900 of the DUT. Then, step 52 is performed to transmit the test signal to the DUT through the probe card 2 to test the DUT.

Claims

1. A probe card, suitable for performing a wafer acceptance test on a wafer, characterized in that: The probe card includes: a circuit board; a cantilever transfer converter electrically connected to the circuit board; and A vertical probe head is electrically connected to the cantilever type transfer converter, and the vertical probe head includes: A probe seat, comprising 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 respectively having an upper surface and a lower surface, and an accommodating space being formed between the lower surface of the upper guide plate unit and the upper surface of the lower guide plate unit; and A vertical probe, comprising a needle tail, a needle body and a needle head, wherein the needle tail passes through the at least one upper guide hole, the needle body is located in the accommodating space, and the needle head passes through the at least one lower guide hole; Among them, the cantilever adapter converter has a mounting seat and a cantilever adapter pin, the cantilever adapter pin has a fixed section and an exposed section, the fixed section is fixed to the mounting seat, the exposed section is located outside the mounting seat, the fixed section enters from the side of the mounting seat and forms a contact point on the bottom surface of the mounting seat.

2. The probe card according to claim 1, wherein: The cantilever transfer needle has a first transfer needle and a second transfer needle, the first transfer needle is adjacent to the second transfer needle and does not contact each other, the fixed section of the first transfer needle and the second transfer needle has a needle entry section that enters from the side of a fixed portion of the mounting seat, the needle entry section of the cantilever transfer needle also includes a head section away from the side of the fixed portion and a tail section adjacent to the side of the fixed portion, in the head section of the needle entry section of the first transfer needle and the second transfer needle, the corresponding positions of the two needle entry sections have a head shortest distance, and the tail section of the needle entry section of the first transfer needle and the second transfer needle has a tail shortest distance, and the tail shortest distance is greater than the head shortest distance.

3. The probe card according to claim 2, wherein: The shortest distance at the positions corresponding to the needle entry sections of the first transfer needle and the second transfer needle gradually decreases from the position entering the side edge of the fixing portion.

4. The probe card according to claim 1, wherein: The cantilever adapter is arranged 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. The fixing portion is arranged in the first through hole and extends to the upper surface of the base.

5. The probe card according to claim 1, wherein: The circuit board also includes a plurality of leakage current prevention contacts, wherein each of the leakage current prevention contacts is arranged on a base plate, and the base plate is arranged on the circuit board through bonding materials. The leakage current prevention contacts also include a signal circuit pattern, and a protection circuit pattern surrounds the signal circuit pattern.

6. The probe card according to claim 5, wherein: The probe card also includes a plurality of coaxial lines electrically connected to the plurality of leakage current prevention contacts respectively.

7. The probe card according to claim 6, wherein: The circuit board also includes a plurality of through holes for the plurality of coaxial lines or the cantilever transfer pins to pass through.

8. The probe card according to claim 5, wherein: The plurality of anti-leakage current contacts include a plurality of first anti-leakage current contacts on the upper surface of the circuit board, and a plurality of second anti-leakage current contacts on the circuit board, and each of the two ends of the coaxial line is electrically connected to the first anti-leakage current contact and the second anti-leakage current contact, wherein the circuit board has a circuit board central axis along its thickness direction, the first anti-leakage current contact has a first central axis along its thickness direction, and the second anti-leakage current contact has a second central axis along its thickness direction, wherein the radial distance between the first central axis and the circuit board central axis is greater than the distance between the second central axis and the circuit board central axis.

9. The probe card according to claim 1, wherein: It also comprises a reinforcing piece which is detachably arranged on the circuit board, and the mounting seat is connected to the reinforcing piece.

10. The probe card according to claim 9, wherein: The reinforcing piece is locked on the circuit board through a locking element.

11. The probe card according to claim 9, wherein: 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, the reinforcement member has a second through hole corresponding to the first through hole, the fixing portion is arranged in the first through hole and the second through hole, and extends to the upper surface of the base, and a gap is provided between the base and the circuit board for allowing the exposed section of the cantilever adapter pin to pass through.

12. The probe card according to claim 1, wherein: The material of the cantilever transfer pin is an alloy of one or a combination of beryllium, copper, rhenium, tungsten, gold and silver.

13. The probe card according to claim 1, wherein: The contact point of each cantilever transfer pin is an end of the fixed segment pin body or the contact point of each cantilever transfer pin is a contact pad coupled to the end of the fixed segment pin body.

14. The probe card according to claim 1, wherein: The fixing section is cone-shaped.

15. The probe card according to claim 1, wherein: The hardness of the cantilever type transfer needle is greater than 245Mpa, and the resistance of the cantilever type transfer needle is less than 200mΩ.

16. A probe card design method, characterized in that: The probe card includes a circuit board, a cantilever transfer converter and a vertical probe head. The cantilever transfer converter is electrically connected to the circuit board. The vertical probe head is electrically connected to the cantilever transfer converter. The cantilever transfer converter has a mounting seat and a plurality of cantilever transfer pins. The plurality of cantilever transfer pins include two adjacent first transfer pins and a second transfer pin. The probe card design method includes: According to the distance between the first transfer pin and one end of the second transfer pin, under the condition of fixing the distance between the first transfer pin and one end of the second transfer pin, the actual coupling capacitance between the first transfer pin and the second transfer pin is adjusted to meet a coupling capacitance threshold.

17. The probe card design method according to claim 16, wherein: The mounting base of the cantilever adapter converter has a fixed portion, and each of the cantilever adapter pins has a fixed section and an exposed section in sequence, wherein the fixed section is fixed to the fixed portion of the mounting base, and the exposed section is outside the fixed portion, and the exposed section is used to electrically connect the circuit board, wherein the step of adjusting the actual coupling capacitance between the first adapter pin and the second adapter pin includes: The relative distance between the fixing sections of the first transfer pin and the second transfer pin is adjusted to adjust the actual coupling capacitance between the first transfer pin and the second transfer pin.

18. The probe card design method according to claim 17, wherein: The fixing section enters from the side of the fixing portion, and a contact point is formed on the bottom surface of the fixing portion of the mounting seat, each of the contacts is used to electrically contact the needle tail of each of the vertical probes, and the fixing section of the first transfer needle and the second transfer needle has a needle entry section that enters from the side of the fixing portion, and the step of adjusting the relative distance of the fixing section of the first transfer needle and the second transfer needle also includes: The shortest distance for adjusting the corresponding positions of the needle insertion sections of the first transfer needle and the second transfer needle gradually decreases from the position entering the side edge of the fixing portion.

19. A method for testing an object to be tested via a probe card, characterized in that: The following steps are involved: Providing a probe card as claimed in claim 1; Make the needles of the vertical probes of the probe card contact the conductive contacts of the object to be tested correspondingly; and The test signal is transmitted to an object to be tested through the probe card.

20. A system for testing an object to be tested via a probe card, characterized in that: include: A carrying platform, carrying an object to be tested; as well as The probe card as claimed in claim 1 is configured to electrically connect the probe card to the object to be tested by contacting the object to be tested with vertical probes of the probe card.

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