Probe head, probe card, test apparatus, and electronic device test by test apparatus

Abstract

A probe head, a probe card, a test apparatus, and an electronic device to be tested by the test apparatus are described. The probe head comprises a pair of pre-bent probes and a guide plate. The pair of probes electrically connect the electronic device integrated in the semiconductor wafer with the test machine. Each probe comprises a probe head, a probe tail and a probe body. The needle head comprises a contact tip which contacts a corresponding contact area on the electronic device during testing. The needle body extends between the needle head and the needle tail according to a longitudinal development axis, and the cross section of the needle body is perpendicular to the longitudinal development axis. The guide plate is provided with a pair of guide holes configured to slidably accommodate the pair of probes. The pair of probes are arranged in a direction parallel to the cross section, and the direction is substantially perpendicular to the buckling direction of the probes. The cross section of each probe is substantially rectangular, and the center connecting line of the two cross sections passes through the short edge of each cross section.

Description

Technical Field

[0001] The present invention relates to a probe head, a probe card, a test device, and a device under test to be tested by the test device. More specifically, the present invention relates to a probe head, a probe card, a test device, and a device under test to be tested by the test device, in which the minimum allowable distance between each pair of probes is shortened to meet the high-frequency / high-speed test requirements. Background Art

[0002] A probe card is a tool for testing the electrical properties of a semiconductor wafer or a packaged device. Generally, it may at least include a probe head, a space converter, and a circuit board. The probe head may include a plurality of probes, and each probe may contact a contact area integrated on a device under test (DUT) of a semiconductor wafer to test the electrical performance of the device under test. During testing, the probe and the device under test will relatively move at a distance along the longitudinal development axis, that is, the vertical movement of the probe (also known as overdrive / overtravel), which is usually that the fixture carries the device under test and moves upward from the contact height to be closer to the probe, so that the contact tip of the needle head of the probe contacts and presses the contact area of the device under test. This approach can ensure sufficient mechanical contact and good electrical connection between the probe and the device under test.

[0003] In recent years, the high-frequency / high-speed test requirements for devices under test have been increasing day by day. As the data transmission rate during testing increases (for example, from 50-60 gigabits per second (Gbps) to over 100 Gbps), the impedance matching between the entire probe head and the device under test has a more significant impact on high-speed signal transmission. When the impedance of the test path (i.e., the signal transmission path) is mismatched, the influence of return loss will become significant. In high-frequency / high-speed testing, high-speed signal transmission can adopt the form of differential pairs or single-ended signals. However, whether it is the two signal probes of a differential pair (such as two S needles), or the signal probe (S needle) and the ground probe (G needle) in single-ended signal transmission, probe designers all expect to shorten the distance between the two probes as much as possible to reduce the characteristic impedance, because this is beneficial to high-frequency / high-speed signal transmission. On the other hand, with the progress of manufacturing technology, the number of components that an integrated circuit device can accommodate has increased, resulting in an increasingly high proportion of corresponding signal probes in the probe head. As the component spacing on the device under test becomes smaller, the subsequent problem is how to prevent the corresponding signal probes from contacting each other during testing, thereby causing a short-circuit situation.

[0004] In view of this, there is an urgent need in the technical field to which the present invention pertains for a solution that can improve the impedance matching effect of probe pairs (especially differential pairs), while reducing the probability of mutual contact between probes during the testing process. Summary of the Invention

[0005] To at least solve the above technical problems, the present invention provides a probe head. The probe head includes a pair of probes and a guide plate. The pair of probes is configured to electrically connect a device under test integrated in a semiconductor wafer to a testing machine. Each probe includes a needle head portion, a needle tail portion, and a needle body portion. The needle head portion includes a contact tip configured to contact a corresponding contact area on the device under test during testing. The needle body portion extends between the needle head portion and the needle tail portion along a longitudinal development axis, and a transverse cross-section of the needle body portion is perpendicular to the longitudinal development axis. The guide plate is provided with a pair of guide holes configured to slidably accommodate the pair of probes. The pair of probes is a vertical probe. In addition, the pair of probes is arranged along a first direction, the first direction is parallel to the transverse cross-section, and the first direction is substantially perpendicular to a buckling direction of the pair of probes. The respective transverse cross-sections of the pair of probes are substantially rectangular, and a line connecting the two geometric centers of the two transverse cross-sections of the two needle body portions of the pair of probes passes through a short side of each transverse cross-section.

[0006] To at least solve the above technical problems, the present invention further provides a probe card. The probe card is used to integrate an electronic device on a semiconductor wafer and is included in a testing device. The probe card includes a circuit board, a space converter disposed on the circuit board, and the probe head as described above. The probe head is disposed on the other side of the space converter relative to the circuit board, and the needle tail portions of the plurality of probes in the probe head are configured to be electrically connected to the space converter.

[0007] To at least solve the above technical problems, the present invention further provides a testing device. The testing device is used to test an electronic device integrated in a semiconductor wafer, and the testing device includes a fixture, a testing machine, and the probe card as described above. The fixture is used to support the semiconductor wafer. The testing machine is electrically connected to the electronic device to establish an electrical testing program. The probe card is disposed in the testing device.

[0008] To at least solve the above technical problems, the present invention further provides an electronic device that uses the testing device as described above to perform a high-frequency testing program. Among them, the high-frequency testing program is tested by the probe card of the testing device using a high-frequency signal.

[0009] In summary, the probe system provided by the present invention, the probe head, probe card and test equipment therein, by virtue of the arrangement mode in which the probe arrangement direction is substantially perpendicular to the buckling direction, enable the minimum allowable spacing between probe pairs (for example, two signal probes in differential signal transmission, or one signal probe and one ground probe in single-ended signal transmission) to be further reduced compared to the prior art solution where the probe arrangement direction is the same as the buckling direction. That is, the probe pairs on the probe head provided by the present invention can be closer to each other compared to the prior art. This setting can make the characteristic impedance of each probe pair close to the characteristic impedance of the device under test, reduce the resource loss caused by impedance mismatch, and meet the specifications of high-frequency / high-speed transmission.

[0010] The above content provides a basic description of the present invention, including the technical problems solved by the present invention, the technical means adopted, and the technical effects achieved. The following will further illustrate various embodiments of the present invention with examples. Brief Description of the Drawings

[0011] As follows:

[0012] Figure 1A Illustrates a probe card, a probe system where the probe head is located, and an electronic device under test according to one or more embodiments of the present invention.

[0013] Figure 1B Illustrates a cross-section of the body portion of a pre-bent probe made by wire stamping according to one or more embodiments of the present invention.

[0014] Figure 2 Illustrates the positional distribution relationship of the probes in the probe head according to one or more embodiments of the present invention.

[0015] Figure 3 Illustrates from a top-down perspective Figure 2 the arrangement relationship of multiple probes in

[0016] Figure 4 Taking Figure 2 one probe pair in

[0017] Figure 5 as an example, shows the eccentric setting mode of the contact tip of the needle head of the probe relative to the body portion and / or the rest of the needle head according to one or more embodiments of the present invention.

[0018] Figure 6 Taking two probe pairs as an example, shows another eccentric setting mode of the contact tips of the needle heads of the probe pairs relative to the body portion and / or the rest of the needle head according to one or more embodiments of the present invention.

[0018] Figure 6 Taking three probe pairs as an example, shows the eccentric setting mode of the body portion of the probe pair relative to the needle head according to one or more embodiments of the present invention.

[0019] Figure 7 Taking four groups of probe pairs as an example, the setting manners of the insulating spacers and insulating buffers of the probe pairs according to one or more embodiments of the present invention are shown.

[0020] Figures 1A through 7 The content shown is only an example for illustrating the embodiments of the present invention, rather than for limiting the protection scope of the present invention. Detailed implementation manners

[0021] The following embodiments are not intended to limit the invention to be claimed to a specific environment, application, structure, process, or situation. In the attached drawings, components not directly related to the invention to be claimed will be omitted. In the attached drawings, the sizes of the components and the dimensional ratios between the components are also only illustrative examples and are not intended to limit the invention to be claimed. Unless otherwise specified, the same component symbols in the following text may refer to the same components.

[0022] The terminology described herein is only for facilitating the description of the embodiments and is not intended to limit the invention to be claimed. Unless specifically stated otherwise, the singular "a" or "an" shall be regarded as including the plural. Terms such as "comprising", "including", "having", etc. are used to specifically state the existence of the features, integers, steps, operations, components, elements, and / or groups stated thereafter, but do not exclude the existence or addition of one or more other additional features, integers, steps, operations, components, elements, and / or groups, etc. The term "and / or" is used to represent any one or all combinations of one or more related listed items. When terms such as "first", "second", "third", etc. are used to describe components, the purpose is not to limit the components being described, but only to distinguish the components being described. Thus, for example, without departing from the spirit or scope of the invention to be claimed, the first component may also be named the second component.

[0023] Referring to Figure 1A , which shows a test device 101. The test device 101 can be used to test a device under test 102 by contacting with probes, and can at least include a probe card 103, a chuck 104, and a tester 105. The probe card 103 can be used for electrical connection and / or mechanical contact with the device under test 102, and can be used to test the electrical performance of the device under test 102. The probe card 103 can be used to test the device under test 102, and the device under test 102 can be an electronic device formed on semiconductor wafers. The chuck 104 can be used to hold the device under test 102 for the probe card 103 to test the device under test 102.

[0024] The device under test 102 may include one or more contact areas (e.g., Figure 1A the contact area 101 shown), such that the contact area of each probe is configured to contact one of the one or more contact areas during testing of the device under test 102. The form of the contact area varies according to the type of the probe and different types of contact tips on the probe head. For example, a contact area with a bump form on the device under test corresponds to a contact tip with a blunt surface form, while a contact area with a pad form corresponds to a contact tip with a sharp form.

[0025] The probe card 103 may include a circuit board 106, a space converter 107, and a probe head 108. The space converter 107 may be disposed on the circuit board 106, and the probe head 108 may be disposed on the space converter 107. The probe head 108 may basically include a plurality of probes and at least one guide plate. One end of each probe may be electrically connected to the circuit board 106 through the space converter 107, and the other end may contact a contact area (e.g., a metal pad or a conductor bump) on the device under test 102 during testing. It should be noted that the above description that the space converter 107 is disposed on the circuit board 106 is only based on the respective conventional size relationship between the space converter 107 and the circuit board 106, and does not limit that the space converter 107 must be physically above the circuit board 106.

[0026] The testing machine 105 can perform various high-frequency test procedures on the device under test through the probe card 103 and / or communicate test information. A specific example of the testing machine 105 can be the test head of a tester. The high-frequency test procedure refers to a test method that uses high-frequency signals to test and evaluate electronic devices (such as the device under test 102). The main purpose of this test procedure is to ensure the performance, stability, and reliability of electronic devices in a high-frequency operating state. When performing high-frequency tests, the test equipment provides a high-frequency signal (for example, in the frequency range of hundreds of MHz to GHz) and injects it into the electronic device under test. In the test procedure, the applied high-frequency signal can cover various test conditions, such as the amplitude, frequency range, and waveform of the signal. The measurement data during the test is collected and used to analyze the behavior of the electronic device under high-frequency operating conditions. In some test methods, the high-frequency test procedure can include a loopback test, which is a test method in which the device under test 102 itself emits a test signal and then sends it back to the device under test 102 through the probe card 103 in the test equipment 101. During this process, the device under test 102 generates a test signal and sends it back to itself through the probe card 103, so that the test equipment 101 can measure the returned signal to ensure signal transmission and response of the device in a high-frequency environment. The loopback test procedure allows the test equipment 101 to directly analyze the reflection signal, delay, attenuation, and other characteristics inside the device under test 102, and these parameters are crucial for evaluating the signal integrity and performance of the device under high-frequency conditions. High-frequency test procedures are widely used in wireless communication, radar systems, high-speed data transmission devices, and other electronic devices that require high-frequency operation. Through these tests, the working stability of electronic devices in a high-frequency environment can be ensured, and their performance requirements of product design can be met.

[0027] The circuit board 106 may include a wafer side and a tester side. The wafer side of the circuit board 106 and the tester side of the circuit board 106 are oppositely arranged, and the tester side of the circuit board 106 is provided to connect to a test device. In this embodiment, when the probe card 103 is used in the tester 105, the wafer side may be the lower side of the circuit board 106, which may face the space converter 107 and / or the device under test 102, and the tester side may be the upper side of the circuit board 106, which may face away from the device under test 102 and / or face the tester 105. The circuit board 106 is a general printed circuit board in this embodiment. The circuit board 106 has a top surface, a bottom surface, and various signal lines inside it, and contact pads electrically connected to the signal lines are formed on the top surface and the bottom surface. The top pins of the test device touch the contact pads on the top surface of the circuit board 106. The test signals of the test device can be transmitted to the bottom surface of the circuit board 106 via the aforementioned signal lines.

[0028] The space converter 107 may also include a wafer side and a tester side. It should be noted here that the space converter 107 may be composed of multiple circuit boards. The tester side of the space converter 107 can be connected to the wafer side of the circuit board 106. In this embodiment, when the probe card 103 is used in the tester 105, the wafer side of the space converter 107 may be the lower side of the space converter 107, which may face the probe head 108 and / or the device under test 102, and the tester side of the space converter 107 may be the upper side of the space converter 107, which may face away from the device under test 102, face the circuit board 106, and / or face the tester 105. In this embodiment, the space converter 107 may include a multilayer organic (MLO) carrier board or a multilayer ceramic (MLC) carrier board, and its material can be adjusted according to actual needs, and the present invention does not limit this. The space converter 107 has various signal lines inside it, and contact pads electrically connected to the internal signal lines are formed on its top surface and bottom surface, and the pitch between the top surface contact pads is greater than the pitch between the bottom surface contact pads. The space converter 107 is mechanically and electrically connected and disposed on the wafer side of the circuit board 106, that is, the bottom surface of the circuit board 106, and is located below the circuit board 106, so that the contact pads on the top surface of the space converter 107 can be electrically connected to the contact pads on the bottom surface of the circuit board 106, so that the signal lines inside the space converter 107 are electrically connected to the signal lines of the circuit board 106. It should be noted here that between the space converter 107 and the circuit board 106, another carrier board (for example: a spacer board) can also be used to indirectly mechanically and / or electrically connect the space converter 107 to the wafer side of the circuit board 106.

[0029] The probe head 108 can be arranged on the wafer side of the spatial converter 107 in a mechanically and / or electrically connected form. As Figure 1A shown, the probe head 108 can include an upper guide plate unit 109, a lower guide plate unit 110, and a plurality of probes (for example: Figure 1A the probe 111 shown in). Each probe can physically contact the device under test 102. The upper guide plate unit 109 can include at least one upper guide plate, and each of the at least one upper guide plate can be provided with a plurality of upper guide holes. The lower guide plate unit 110 can include at least one lower guide plate, and each of the at least one lower guide plate can be provided with a plurality of lower guide holes. The upper guide plate unit 109 and the lower guide plate unit 110 can be arranged opposite to each other up and down along the longitudinal development axis (for example: substantially along Figure 1A the coordinate axis Z of the local reference system hereinafter simply referred to as the "Z-axis"). Each probe can pass through a corresponding one of the plurality of upper guide holes and a corresponding one of the plurality of lower guide holes.

[0030] Probes are usually made of special metals with good electrical and mechanical properties. By pressing the probe head 108 onto the device under test 102, a good connection between the contact area of the probe and the device under test 102 can be ensured. During the pressing contact, the probe can slide within the corresponding guide holes on the upper and lower guide plate units, and the probe can be bent within the air gap between the upper and lower guide plate units.

[0031] Each probe included in the probe head 108 provided by the present invention can be a probe known in the art as a pre-bent probe (also known as a "cobra"), which is a probe with a bent shape similar to the head of a cobra. This shape gives the probe good compliance and can make contact without damaging the device under test. Such probes can be made of materials such as, but not limited to, spring steel or beryllium copper, and are manufactured by processes such as stamping or etching. The shank portion of the probe can have a constant transverse cross-section throughout its entire length (for example: substantially rectangular, preferably square or rectangular). When the probe is made by wire stamping, only the shank portion will have a substantially rectangular transverse cross-section, and the tip portion and the tail portion of the probe can maintain the original circular transverse cross-section of the wire. Therefore, the corresponding guide holes on the upper guide plate unit 109 and the lower guide plate 110 can be substantially circular. In an embodiment made by wire stamping, the shank portion of the probe will have a "substantially rectangular" transverse cross-section, where the so-called "substantially rectangular" specifically means that each of the two relatively long sides can be a flat straight line (corresponding to the flat surface formed after the wire of the shank portion is stamped), and the other two relatively short sides can each be slightly arc-shaped (corresponding to the curved surface of the wire of the shank portion that is not directly stamped). A specific example thereof can be as Figure 1BAs shown by a transverse cross-section 121 therein. Two opposite long sides 122 and 123 of the transverse cross-section 121 are each flat and straight, while two opposite short sides 124 and 125 are each arc-shaped. However, in addition to being manufactured by wire stamping, the probes on the probe head 108 can also be made in the way of Micro-Electro-Mechanical Systems (MEMS). At this time, in some embodiments, the head and tail parts of the probes can have a rectangular transverse cross-section like the body part of the probes. Therefore, the corresponding guide holes on the upper guide plate unit 109 and the lower guide plate 110 can be substantially rectangular. According to different embodiments, all the probes on the probe head 108 can be made by wire stamping, all can be made by MEMS, or the two types can coexist in the same implementation mode. Correspondingly, the multiple guide holes on the upper guide plate unit 109 and the lower guide plate 110 corresponding to the probes can all be substantially circular, all can be substantially rectangular, or the two types can coexist in the same implementation mode. If the probes on the probe head 108 are in the situation where the two types coexist as described above, it is preferably that the signal probes are made by MEMS, and other non-signal probes (such as ground probes, power probes, etc.) are made by stamping or etching.

[0032] As used herein, "substantially rectangular" refers to a rectangle and other actual results that may occur in order to manufacture the transverse cross-section of the probe body part and the guide hole in the shape of a rectangle, such as a trapezoid. More specifically, those of ordinary skill in the art to which the present invention pertains should understand that even if the equipment for manufacturing the probe or the guide plate is designated to produce a probe or a guide hole with a rectangular transverse cross-section, the actually produced transverse cross-section of the probe or the guide hole may still have a certain tolerance or manufacturing error, such that the shape of the transverse cross-section of the probe body part of the probe or the guide hole is not a geometrically perfect rectangle in some embodiments. Similarly, as used herein, "substantially circular" refers to a circle and other actual results that may occur in order to manufacture the transverse cross-section of the probe body part and the guide hole in the shape of a circle, such as an ellipse. More specifically, those of ordinary skill in the art to which the present invention pertains should understand that even if the equipment for manufacturing the probe or the guide plate is designated to produce a probe or a guide hole with a circular transverse cross-section, the actually produced transverse cross-section of the probe or the guide hole may still have a certain tolerance or manufacturing error, such that the shape of the transverse cross-section of the probe body part of the probe or the guide hole is not a geometrically perfect circle in some embodiments.

[0033] As will be described below with Figure 1ATaking the probe 111 shown as an example, the basic structure of each probe in the probe head 108 will be described. The probe 111 may include a needle head portion 112, a needle tail portion 113, and a needle body portion 114 located between the needle head portion 112 and the needle tail portion 113. The needle head portion 112 may end at a contact tip 115 and may be configured to be adjacent to a corresponding contact area 116 of the device under test 102.

[0034] The needle tail portion 113 of the probe 111 may pass through a guide hole in the upper guide plate unit 109 to be electrically connected to the space converter 107. The needle tail portion 113 may end at a contact head and may be configured to be adjacent to a contact area (not shown in the figure) of the space converter 107. The needle body portion 114 may extend substantially along the longitudinal development axis between the needle head portion 112 and the needle tail portion 113. In some embodiments, the probe length of each probe in the probe head 108 from the contact tip of the needle head to the contact tip of the needle tail may be between 3 millimeters and 8.2 millimeters. In some embodiments, the probe length may also be not greater than 6 millimeters, and more preferably not greater than 4 millimeters.

[0035] The needle head portion 112 can be used for making electrical contact with the device under test 102, that is, it can be configured to perform electrical communication and / or contact communication with the corresponding contact area of the device under test 102. The communication means that the probe can be configured to transmit the test signal of the probe card 103 to the device under test 102, and / or be configured to receive signals from the device under test 102.

[0036] The plurality of probes included in the probe head 108 as a whole may include a plurality of probe pairs. These probe pairs may be composed of differential pairs and / or single-ended signal probe pairs, and their distribution ratios vary according to the embodiments. Each differential pair of probes can be used to transmit a set of differential signals. In the preferred embodiment of the present invention, the differential pair can use two single-ended signal lines (for example: P line and N line) to connect TX+ and RX+, and TX- and RX- respectively to transmit signals simultaneously, and these two signals have the same signal voltage amplitude but opposite signal phases. Each single-ended signal probe pair can be composed of a signal probe (for transmitting a single-ended signal) and a ground probe (for contacting the ground pad on the device under test).

[0037] In the probe head 108, each pair of probes can be arranged in a first direction, which can be parallel to the transverse cross-section of the needle body portion of the probe, and this first direction can be substantially perpendicular to a bending direction of the pair of probes. The transverse cross-section refers to a cross-section obtained by the intersection of an imaginary plane perpendicular to the longitudinal development axis (i.e., the Z-axis direction in the figure) and the needle body portion. The bending direction refers to the direction in which the needle body portion is further bent due to force when the probe contacts the corresponding contact area of the device under test 102. Taking Figure 1ATaking the probe 111 and the other three probes 117, 118, and 119 shown as an example, the direction of their buckling is the positive direction of the coordinate axis X of the local reference system (hereinafter simply referred to as the "X-axis"). The so-called substantially perpendicular means that in addition to an exact angle of 90 degrees, it may also include errors common to those of ordinary skill in the art to which the present invention pertains, such as errors within plus or minus 5 degrees.

[0038] Figure 1A Although the probes 111, 117, 118, and 119 are shown in [reference], these four probes do not jointly form any differential probe pair / single-ended signal probe pair. The other probe of the differential pair to which these four probes belong is not shown in Figure 1A In terms of the perspective of Figure 1A , the other probe of the probe pair to which these four probes belong is arranged along the direction in and out of the paper surface beside the corresponding probe.

[0039] Referring to Figure 2 , taking a local structure of the probe head 201 as an example, it shows the possible arrangement directions, buckling directions, and spacing relationships of the probe pairs on the probe head provided by the present invention. First, referring to Figure 2 , the probe head 201 may include multiple probes, such as the probes 202, 203, 204, 205, 206, 207, 208, and 209 shown in the figure. The probe head 201 may also include an upper guide plate unit 210 and a lower guide plate unit 211. The tail ends of the respective probes may pass through the corresponding upper guide holes in the upper guide plate unit 210, and the head ends may pass through the corresponding lower guide holes in the lower guide plate unit 211.

[0040] The probe 203 and the probe 204 may form a probe pair (such as, but not limited to, a differential pair), and the probe 207 and the probe 208 may also form a probe pair. The probes 202, 205, 206, and 209 may also belong to other probe pairs, but they do not jointly form any probe pairs in the Figure 2 shown scenario. In Figure 2 , the probes 202, 203, 204, and 205 form a ground-signal-signal-ground (GSSG) configuration, and the probes 206, 207, 208, and 209 also form a ground-signal-signal-ground (GSSG) configuration.

[0041] As shown in Figure 2As shown, the probe pairs formed by probe 203 and probe 204, where probe 203 and probe 204 are arranged along the direction parallel to the coordinate axis Y of the local reference system (hereinafter referred to as the "Y-axis"), and the buckling directions of these two probe pairs are both in the positive direction of the X-axis. That is, the probe arrangement directions of these two probe pairs (whether in the positive or negative direction of the Y-axis) are substantially perpendicular to the buckling directions of their own probes. The probe pairs formed by probe 207 and probe 208, where probe 207 and probe 208 are arranged along the direction parallel to the coordinate axis Y of the local reference system (hereinafter referred to as the "Y-axis"), and the buckling directions of these two probe pairs are both in the positive direction of the X-axis. That is, the probe arrangement directions of these two probe pairs (whether in the positive or negative direction of the Y-axis) are substantially perpendicular to the buckling directions of their own probes.

[0042] Figure 3 Taking Figure 2 probe 202, probe 203, probe 204, and probe 205 in as an example, the relationship between the probe arrangement direction and the buckling direction is shown from a top-down perspective. Referring to Figure 3 , the transverse cross-sections of the shank portions of probe 202, probe 203, probe 204, and probe 205 can be substantially rectangular. The probe arrangement direction (i.e., the direction parallel to the Y-axis) is substantially perpendicular to the buckling direction 303 of the probe. In addition, for the probe pair of probe 203 and probe 204, a connecting line 304 between the two geometric centers 301 and 302 of their shank portion transverse cross-sections passes through a short side of their respective transverse cross-sections. That is, probe 203 and probe 204 of the probe pair are opposite with the short sides of the shank portions. It should be noted that Figure 3 what is shown is the transverse cross-section of the shank portion of each probe, which is only a schematic view and not the result that can be seen when actually observing the probe head 201 from a top-down perspective.

[0043] Through the arrangement that the probe arrangement direction is substantially perpendicular to the buckling direction of its own probe, when each probe pair is bent under force during testing, it is less likely to contact each other and cause negative results such as interference, short circuit, or even structural damage to each other. Therefore, compared with the state where the buckling direction is consistent with the probe arrangement direction, the minimum allowable distance between each probe pair on the probe head provided by the present invention can be reduced to a smaller value.

[0044] Regarding the minimum allowable spacing, more specifically, it may at least refer to the minimum allowable spacing of one of the center spacing of the shank portions between two probes, the inner edge spacing of the shank portions, and the center spacing of the probe heads. It should be noted that even though the present invention shortens the minimum allowable spacing through the above mechanism, this does not mean that the distance values such as the center spacing of the shank portions, the inner edge spacing of the shank portions, and the center spacing of the probe heads of each probe pair in all implementation aspects of the present invention must be in the shortest state, but only indicates that the present invention has a greater arrangement space compared with the background technology.

[0045] In addition, in some embodiments, the two probes on each probe pair can be the closest to each other among all the probes. Specifically, the inner edge spacing D1 between the shank portions of probe 203 and probe 204 can be smaller than the inner edge spacing between these two probes and other probes, that is, the spacing between the two probes of the probe pair can be the smallest among the spacings between any two of the multiple probes included in the probe head 201. The inner edge spacing refers to the surface spacing between the two surfaces of the two probes facing each other. For example, the inner edge spacing D1 between the shank portions of probe 203 and probe 204 can be smaller than the inner edge spacing D2 between probe 203 and probe 202. The inner edge spacing D1 between the shank portions of probe 203 and probe 204 can also be smaller than the inner edge spacing D3 between probe 204 and the adjacent probe 208. In addition, the center spacing D4 (for example, can be between 120 micrometers and 170 micrometers) of the shank portions between probe 203 and probe 204 can also be smaller than the center spacing between these two probes and other probes.

[0046] In addition to shortening the minimum allowable spacing by arranging the probe direction substantially perpendicular to the probe buckling direction, the present invention also provides other solutions that can substantially shorten the probe spacing and implement them in combination. In some embodiments, the center spacing D4 of the shank portions of probe 203 and probe 204 can be set to be smaller than the center spacing D5 of the corresponding two contact areas 212 and 213 on the device under test. At this time, since the above inner edge spacing D1 is smaller than the center spacing D4, it will naturally be smaller than the center spacing D5. To achieve this result, the contact tips of the probe heads of the probes can be configured to be eccentric with respect to the shank portions of the same probe. For a more specific example, please first refer to Figure 4 , which illustrates from a top view Figure 2 a feasible offset method of the contact tips of the probe heads of probe 203 and probe 204 in Figure 4 shown can represent a direction along a hypothetical X-Y plane parallel to the X-axis and the Y-axis towards Figure 2The transverse cross-sections 401 and 402 respectively cut out from the shank portions of the probes 203 and 204, and the transverse cross-sections 403 and 404 respectively cut out from the contact tips of the probe heads of the probes 203 and 204 in another imaginary X-Y plane at different Z-axis heights.

[0047] As Figure 4 shown, the geometric center 405 of the transverse cross-section of the contact tip of the probe 203 can deviate from the geometric center 301 of the transverse cross-section of the shank portion of the probe 203 in the positive direction of the X-axis by a distance D6 and in the negative direction of the Y-axis by a distance D7. On the other hand, the geometric center 406 of the transverse cross-section of the contact tip of the probe 204 can deviate from the geometric center 302 of the transverse cross-section of the shank portion of the probe 204 in the positive direction of the X-axis by a distance D8 and in the positive direction of the Y-axis by a distance D9. This structural arrangement (especially the setting of moving away from each other in the direction of the connection line of the shank portion and / or the probe head portion, that is, the deviation of the two probes in the positive and negative directions of the Y-axis in the figure) allows the shank portions of the double probes to be further shortened in the case where the center pitch of the contact tips of the probe heads of the probe pair (corresponding to the center pitch D5 of the two contact areas 212 and 213 on the device under test, for example, can be between 120 microns and 170 microns) remains fixed, so that the center pitch D4 of the shank portions of the probe 203 and the probe 204 can be less than the center pitch D5 of the corresponding two contact areas 212 and 213 on the device under test. Specifically, for a set of probe pairs, since the center pitch of the contact tips of the two probes will generally need to be the same as the center pitch of the contact areas on the device under test, and considering that the center pitch of the contact areas (or the pitch between the two positions on the device under test contacted by the probe contact areas during other tests) may not be a specification that can be determined by the probe manufacturer, this eccentric setting of the contact tips of the probe heads enables the two probes in a probe pair to further shorten the pitch of the two shank portions while the center pitch of the two contact tips remains fixed, thereby improving the electrical performance of the probe pair as a differential pair. In some embodiments, the center pitch D5 of the two contact areas of the device under test can be between 130 microns and 220 microns.

[0048] In some embodiments, each probe pair on the probe head provided by the present invention can also only move away from each other in the direction of the connection line of the shank portion and / or the probe head portion. If the example in Figure 4 is used to describe, that is, the geometric center 405 of the transverse cross-section of the contact tip of the probe 203 can only deviate from the geometric center 301 of the transverse cross-section of the shank portion in the negative direction of the Y-axis by a distance D7, and the geometric center 406 of the transverse cross-section of the contact tip of the probe 204 can also only deviate from the geometric center 302 of the transverse cross-section of the shank portion in the positive direction of the Y-axis by a distance D9.

[0049] Although Figure 4 the figures shown are transverse cross-sections 401 and 402 respectively cut out from the shank portions of the probes 203 and 204 in the imaginary X-Y plane shown in Figure 2 and transverse cross-sections 403 and 404 respectively cut out from the contact tips of the probe heads of the probes 203 and 204 in another imaginary X-Y plane at different Z-axis heights, in some embodiments, Figure 4 the figures shown may also represent the eccentric setting modes on the probe heads of each probe pair, that is, the transverse cross-section 401 and the transverse cross-section 402 may be respectively changed to represent the transverse cross-sections of the remaining parts of the two probe heads except for the contact tips.

[0050] In addition to being offset in the form shown for the probe heads of each probe pair provided by the present invention, Figure 4 it may also be a way that the two contact tips are offset outward along the direction away from each other. Figure 5 That is, taking two probe pairs as an example, another eccentric setting mode of the contact tips of the probe heads of the probes according to one or more embodiments of the present invention relative to the shank portion and / or the remaining part of the probe head is shown.

[0051] Referring to Figure 5 , for the probe pair 501 shown on the left half, the probe head has not been offset, and among the two probes of the probe pair 502 shown on the right half, an angle 504 may be formed between the geometric center line of the contact tip of the probe 503 on the left and the longitudinal development axis. The angle 504 may be formed by the contact tip of the probe 503 in the direction away from the other one of the probe pair (i.e., Figure 5 the negative direction of the Y-axis in Figure 5 ) and may be an acute angle. Relatively, an angle 506 may be formed between the geometric center line of the contact tip of the probe 505 on the right and the longitudinal development axis. The angle 506 may be formed by the contact tip of the probe 505 in the direction away from the other one of the probe pair (i.e.,

[0052] the positive direction of the Y-axis in Figure 4 and Figure 5 ). It should be understood that "the probe head is eccentrically arranged relative to the shank portion" may also be regarded as "the shank portion is eccentrically arranged relative to the probe head", but the two may respectively focus on the additional settings made for the probe head or the shank portion. Figure 5 What is shown in Figure 6 mainly focuses on the eccentric setting made for the probe head, while taking three probe pairs as an example, shows the eccentric setting mode of the shank portion relative to the probe head according to one or more embodiments of the present invention.

[0053] Referring to Figure 6 , among the probe pairs shown on the left half, the probe pair 601 has a state where the needle body part is not offset relative to the needle tip part. Among the probe pairs shown in the middle part, the probe pair 602 has a state where the needle body part is offset but not thickened. And among the probe pairs shown on the right half, the probe pair 603 has a state where the needle body part is offset and thickened at the same time. More specifically, for each of the two probes of the probe pair 601, the geometric center line of the needle body part is non-eccentrically arranged relative to the geometric center line of the needle tip part. For each of the two probes of the probe pair 602, the geometric center lines 604, 605 of the needle body parts deviate towards the side facing the other probe from the geometric center lines 606, 607 of their own needle tip parts. Therefore, compared with the probe pair 601, it shows a result of concentrating inwards. The arrangement on the probe pair 602 enables the inner edge distance between the needle body parts of the two probes to be further reduced. For each of the two probes of the probe pair 603, the geometric center lines 608, 609 of the needle body parts are the same as those of the probe pair 602, deviating towards the side facing the other probe from the geometric center lines 610, 611 of their own needle tip parts. However, in addition, each of the needle body parts of the two probes has an increased thickness on the side facing the other probe compared to the rest of the needle body part, so that the inner edge distance between the needle body parts of the two probes can be further reduced compared to the situation of the probe pair 602.

[0054] In view of the arrangement provided by the present invention, the distance between the needle body parts of each probe pair can be minimized as much as possible. Therefore, in some embodiments, relevant measures can also be provided between the two probes of each probe pair to maintain the inner edge distance of the needle body parts and / or prevent the needle body parts from contacting each other due to bending under force during the test. More specific examples are as follows Figure 7 shown. Taking four probe pairs 701, 702, 703, 704 as examples, it shows the arrangement of the insulating spacer and insulating buffer of the probe pair according to one or more embodiments of the present invention.

[0055] Referring to Figure 7, in some embodiments, at least one common insulating spacer may be provided on the two shank portions of the two probes of each probe pair, and the at least one insulating spacer can be used to maintain a distance between the two shank portions at all times. For example, a common insulating spacer 705 is provided between the shank portions of the two probes of probe pair 701, and probe pair 702 is provided with a plurality of insulating spacers 706, 707, 708 that are separated in a direction parallel to the longitudinal development axis. The insulating spacer can be used to maintain the distance between the two probes. As its name implies, the insulating spacer may be made of an insulating material, such as but not limited to insulating glue, reinforced plastic, plastic steel, etc. In some embodiments, the material of the insulating spacer may be a porous filling material. In some embodiments, the material of the insulating spacer may have a relative dielectric constant not greater than 6. In some embodiments, the material of the insulating spacer may even have a relative dielectric constant not greater than 4. In some embodiments, the relative dielectric constant of the material of the insulating spacer may not be greater than the relative dielectric constant of the material of each upper guide plate in the upper guide plate unit 314 and the material of each lower guide plate in the lower guide plate unit 315.

[0056] In some embodiments, at least one of the two shank portions of the two probes of each probe pair may be provided with at least one insulating buffer, and the insulating buffer can be used to prevent the two shank portions from contacting each other during the test. For example, insulating buffers 709, 710, 711 are provided between the two probes of probe pair 703, specifically on the probe located on the left side in the figure. Insulating buffers 712, 713, 714 are also provided between the two probes of probe pair 704. However, the difference from probe pair 703 is that insulating buffers are provided on the shank portions of both probes in probe pair 704. It should be understood that the manner of providing insulating buffers on the shank portions of both probes is not limited to Figure 7 the manner of being staggered left and right along the longitudinal development axis in probe pair 704 as exemplified. The insulating buffer, like the above-mentioned insulating spacer, may be made of an insulating material, such as but not limited to reinforced plastic, plastic steel, etc. However, since its purpose is not to maintain the inner edge distance of the shank portions of the two probes at all times, the requirement standard for rigidity of the insulating buffer in terms of material can be slightly reduced compared to the insulating spacer. For example, it can also be made of general plastic, high-density foam, etc.

[0057] Next, please refer back to Figure 2。In some embodiments, the two guide holes 214 and 215 on the lower guide plate unit 211 for accommodating the probes 203 and 204 may include two opposite sides, and the lengths of each of the two opposite sides may be the shortest compared to the other sides in the respective guide holes. In addition, in some embodiments, the center-to-center spacing of the guide holes 214 and 215 in the lower guide plate unit 211 for accommodating the probes 203 and 204 may be less than the center-to-center spacing D5 of the corresponding two contact areas on the device under test, and the center-to-center spacing of the guide holes 214 and 215 may be between 120 micrometers and 170 micrometers in some further embodiments.

[0058] Next, please refer back to Figure 1A 。In some embodiments, the contact tips of the needle heads of the two probes of each probe pair may have an expanded area 120 due to being thickened (e.g., Figure 1A the gray translucent area of the probe 118 in), such that the center-to-center spacing of the two contact tips of the needle heads of the probe pair may be less than the center-to-center spacing of the corresponding two contact areas on the device under test (i.e., the edge areas of the thickened contact tips are used to normally contact the device under test contact areas with a larger center-to-center spacing than the contact tips). Specifically, thickening the contact tips can make the transverse diameter of the contact tip of the needle head of each probe greater than the transverse diameter of the remaining part of the needle head (i.e., the other parts except the contact tip), and even further greater than the transverse diameter of the shank portion of the respective probe in some embodiments. The transverse diameter refers to the diameter of the cross-sectional area intercepted by a hypothetical plane (i.e., the X-Y plane) perpendicular to the longitudinal development axis (i.e., the Z axis) for each target part. For a probe pair, it may also refer to the thickness of the target part in the direction of the center line connecting the two probes.

[0059] The contact tips can be thickened during the production process, and the specific method can be to thicken them integrally in the form of covering the entire contact tip (e.g., Figure 1AIn the case illustrated by probe 118, the overall shape of the contact tip after being thickened is not limited to the shown rectangle, but can be other shapes, or it can also be thickened uniformly along the outer edge of the contact tip), or only thickened locally in the direction of the center line of the probe (i.e., the part facing each other between two probes). However, the method of thickening the contact tip is not limited to electroplating. For example, for a microelectromechanical probe (MEMS Wire), the thickness of the contact tip can be increased through a microelectromechanical process. When the contact tip of each probe is thickened, the area of the contact region where it contacts the device under test will also increase, thereby providing a more stable contact method. In particular, in the case where the minimum allowable spacing between probe pairs in the present invention is reduced, and the probe manufacturer indeed designs the center spacing of the contact tips of the probe pairs to approach the minimum allowable spacing, the thickened contact tip will still be able to normally contact the corresponding contact region through the more marginal area. The increase in the lateral diameter of the thickened contact tip can be 102% to 130% of the lateral diameter of at least one of the remaining part of the needle head and the needle body, and preferably 116%, specifically can be between 1 and 15 microns, and preferably can be between 6 and 10 microns. Taking the example of thickening (i.e., increasing the diameter) the contact region of a cobra probe by electroplating, when the thickness of the needle head of the probe is 50 microns, a thickness of 6 to 10 microns can be formed in the corresponding contact region, and at this time the thickness of the thickened contact tip is 56 to 60 microns.

[0060] It should be noted that the above descriptions of each section for probe 203 and probe 204 can also be applied to probe 207 and probe 208, as well as each probe pair on the probe head provided by the present invention. Those of ordinary skill in the art to which the present invention pertains should be able to clearly understand the implementation methods in other probe pairs on the probe head of the present invention based on the above descriptions of probe 203 and probe 204.

[0061] In summary, the probe system provided by the present invention, the probe head, probe card, and test equipment therein, by virtue of the arrangement method in which the probe arrangement direction is substantially perpendicular to the buckling direction, enable the minimum allowable spacing between two probes (e.g., differential pairs) to be further reduced compared to the scheme in which the arrangement direction is the same as the buckling direction, that is, the two needles can approach each other further compared to the background art. This arrangement can make the characteristic impedance of a differential pair close to the characteristic impedance of the device under test, reducing the resource loss caused by impedance mismatch and meeting the specifications of high-frequency / high-speed transmission. The more pairs of probes (e.g., differential pairs) on the probe head to which the above mechanism provided by the present invention is applied, the higher the improvement effect can be obtained.

[0062] The above embodiments are only used to enumerate some implementation aspects of the present invention and to explain the technical features of the present invention, rather than to limit the protection scope and range of the present invention. Any changes or equivalent arrangements that can be easily completed by those of ordinary skill in the technical field to which the present invention pertains fall within the scope claimed by the present invention, and the scope of the present invention's protection rights is subject to the claims.

Claims

1. A probe head, characterized in that: Include: A pair of probes are configured to electrically connect a device under test integrated in a semiconductor wafer to a test equipment, and each probe comprises: A needle head including a contact tip configured to contact a corresponding contact area on the device under test during testing; The end of a needle; and a needle body portion extending between the needle head portion and the needle tail portion according to a longitudinal development axis, and a transverse cross section of the needle body portion is perpendicular to the longitudinal development axis; and a guide plate unit provided with a pair of guide holes configured to slidably accommodate the pair of probes; Wherein, the pair of probes are pre-bent probes; The pair of probes are arranged along a first direction, the first direction is parallel to the transverse cross section, and the first direction is substantially perpendicular to a buckling direction of the pair of probes; and The respective transverse cross-sections of the pair of probes are substantially rectangular, and a line connecting two geometric centers of the two transverse cross-sections of the two needle bodies of the pair of probes passes through a short side of each transverse cross-section.

2. The probe head according to claim 1, characterized in that: An inner edge distance between the two needle bodies of the pair of probes is smaller than an inner edge distance between each of the two needle bodies of the pair of probes and the needle body of the other probe on the probe head.

3. The probe head according to claim 2, characterized in that: The center distance between the pair of probes is a center distance between the two needle body parts of the pair of probes, and is smaller than the center distance between the two corresponding contact areas on the device to be tested.

4. The probe head according to claim 2, characterized in that: The center distance between the pair of probes is a center distance between two contact tips of two needle heads of the pair of probes, and is smaller than the center distance between two corresponding contact areas on the device to be tested.

5. The probe head according to claim 1, characterized in that: The guide plate unit is a lower guide plate, and a center distance between the pair of guide holes on the guide plate unit for accommodating the pair of probes is smaller than a center distance between the corresponding two contact areas on the device to be tested.

6. The probe head according to any one of claims 2 to 5, characterized in that: At least one of the center spacing of the pair of probes, the center spacing of the two needle bodies of the pair of probes, the center spacing of the two contact tips of the two needle heads of the pair of probes, and the center spacing of the pair of guide holes on the guide plate unit that accommodate the pair of probes is between 120 microns and 170 microns, and the center spacing of the corresponding two contact areas on the device to be tested is between 130 microns and 220 microns.

7. The probe head according to claim 1, characterized in that: A transverse diameter of each of the two contact tips of the pair of probes is larger than a transverse diameter of at least one of the remaining portion of the needle head and the needle body of the same probe.

8. The probe head according to claim 1, characterized in that: A transverse diameter of each of the two contact tips of the pair of probes is 102% to 130%, and preferably 116%, of a transverse diameter of at least one of the remaining portion of the needle head and the needle shaft of the same probe.

9. The probe head according to claim 1, characterized in that: A length of each of the pair of probes from the contact tip of the needle head to a contact tip of the needle tail is between 3 mm and 8.2 mm, and preferably is not greater than 4 mm.

10. The probe head according to claim 1, characterized in that: The guide plate unit is a lower guide plate. The pair of guide holes on the guide plate unit for accommodating the pair of probes include two sides opposite to each other, and the length of each of the two sides opposite to each other is the shortest compared with other sides in the corresponding guide holes.

11. The probe head according to claim 1, characterized in that: The center of the contact tip of at least one of the two probes is configured to have an offset in at least one direction perpendicular to the longitudinal development axis compared to the center of the needle body of the same probe.

12. The probe head according to claim 11, characterized in that: A geometric center line of each of the two needle body parts of the two probes is deviated from a geometric center line of the needle head part of the corresponding probe toward a side facing the other of the two probes.

13. The probe head according to claim 12, characterized in that: The two needle shafts of the two probes each have an enlarged thickness at a side facing the other of the two probes compared to the rest of the needle shaft.

14. The probe head according to claim 1 or 13, characterized in that: At least one common insulating spacer is disposed on the two needle body parts of the two probes, and the at least one insulating spacer is used to maintain a distance between the two needle body parts.

15. The probe head according to claim 1 or 13, characterized in that: At least one of the two needle body parts of the two probes is provided with an insulating buffer, and the insulating buffer is used to prevent the two needle body parts from contacting each other during the test process.

16. The probe head according to claim 1, characterized in that: A geometric center line of the contact tip of one of the two probes has an angle with the longitudinal development axis, and the angle is formed by the contact tip deviating from a direction of the other of the two probes.

17. The probe head according to claim 1, further comprising a plurality of signal probes and a plurality of other probes which are non-signal probes, characterized in that: The plurality of signal probes are all micro-electromechanical probes, and the plurality of guide holes on the guide plate unit for accommodating the plurality of signal probes are all substantially rectangular; The other probes are not micro-electromechanical probes, and the guide holes on the guide plate unit for accommodating the other probes are substantially circular; and The pair of probes is two of the plurality of signal probes.

18. The probe head according to claim 1, further comprising a plurality of signal probes and a plurality of other probes which are non-signal probes, characterized in that: The plurality of signal probes are all micro-electromechanical probes, and the plurality of guide holes on the guide plate unit for accommodating the plurality of signal probes are all substantially rectangular; The other probes are not micro-electromechanical probes, and the guide holes on the guide plate unit for accommodating the other probes are substantially circular; and One of the pair of probes is one of the plurality of signal probes, and the other is one of the plurality of other probes and is a ground probe.

19. A probe card for testing an electronic device integrated on a semiconductor wafer and included in a testing device, characterized in that: The probe card contains: a circuit board; a space transformer disposed on the circuit board; and The probe head according to claim 1 is disposed on the other side of the space transformer relative to the circuit board, and the needle tails of each of the plurality of signal probes in the probe head are configured to be electrically connected to the space transformer.

20. A testing device for testing an electronic device integrated in a semiconductor wafer, characterized in that: The test equipment includes: a fixture for supporting the semiconductor wafer; a tester electrically connected to the electronic device for establishing an electrical test procedure; and A probe card according to claim 19, disposed in the testing equipment.

21. An electronic device, wherein the electronic device is subjected to a high frequency test procedure using the test equipment according to claim 20, characterized in that: The high frequency test procedure is performed by the probe card of the test equipment using a high frequency signal.

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