Probe head structure
By using a pin bridge to connect the probe arm in the probe head structure to form an electrical signal path, the problems of impedance mismatch and parasitic capacitance in high-frequency signal testing of existing probe cards are solved, and higher testing accuracy is achieved.
Patent Information
- Application Number
- CN202422187022.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2034-09-06
AI Technical Summary
Existing probe cards suffer from impedance mismatch and parasitic capacitance issues that affect test accuracy in high-frequency signal testing, making it difficult to meet the ever-increasing demands for high-frequency signal transmission.
Design a probe head structure comprising multiple perforated guide plates and first and second probes, with the first and second probe arms connected by a needle bridge to form an electrical signal path, reducing heterogeneous contact points and signal loop length, and lowering the impedance of the signal loop.
It effectively improves the accuracy of high-frequency signal testing, reduces the equivalent RC of the signal circuit, and enhances the precision of the test.
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Figure CN223450023U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to a probe head structure. In particular, the present disclosure relates to a probe head structure having needle bridges connecting multiple needle arms. BACKGROUND
[0002] In semiconductor manufacturing process, a wafer is tested by a probe card to ensure the reliability of the wafer and chip process, so as to filter out defective wafers and chips. The probe card serves as a signal transmission interface for detection, and the probe is an important component for electrical testing. The probe is used to electrically connect with the contact pads on the chip to test whether the function is normal.
[0003] For the rapidly changing semiconductor technology, the signal transmission between electronic components on the chip also needs to be faster and faster. The electrical test using the probe card also needs to meet such high frequency requirements to effectively reflect the performance of the chip. For example, when the probe card is used to transmit the high frequency signal generated on the chip to the tester, and then the high frequency signal is transmitted back to the chip through the probe card, the impedance, parasitic capacitance and other undesirable factors on this path affect the quality of high frequency signal transmission, and further affect the accuracy of the test. Moreover, in some prior art, the high frequency signal generated by the chip under test is transmitted back to the chip under test by using the guide plate or other conductive layer on the probe card, so as to achieve the purpose of high frequency test. However, because of the impedance matching and / or parasitic capacitance and other factors between the guide plate or other conductive layer and the probe, there is still non-negligible interference for high frequency signal test. Therefore, how to improve the quality of high frequency test is an important issue in the field.
[0004] The above description of the prior art is only provided as background technology, does not recognize the above description of the prior art as disclosing the subject matter of the present disclosure, does not constitute the prior art of the present disclosure, and any description of the above "prior art" should not be considered as any part of the present disclosure. SUMMARY
[0005] Therefore, in order to solve the problem of low test efficiency in the prior art, the purpose of the present disclosure is to provide a test system.
[0006] One embodiment of the present disclosure provides a probe head structure comprising a guide plate having a plurality of perforations and a first probe. The first probe comprises a first needle arm, a second needle arm, a first head, a second head, a first stopper, a second stopper, and a needle bridge. The first needle arm passes through a first perforation among the plurality of perforations and is disposed below the guide plate. The second needle arm passes through a second perforation among the plurality of perforations and is disposed below the guide plate. The first head is disposed on the first needle arm and is located above the guide plate. The second head is disposed on the second needle arm and is located above the guide plate. The first stopper is disposed between the first head and the first needle arm and is located above the guide plate. The second stopper is disposed between the second head and the second needle arm and is located above the guide plate. The needle bridge connects the first head and the second head. The first needle arm and the second needle arm form an electrical signal path through the needle bridge. The first needle arm is used to receive a signal from a first contact pad of an object to be tested, and the signal passes through the first needle arm, the first head, the needle bridge, the second head, and the second needle arm in sequence to the second contact pad of the object to be tested.
[0007] In some embodiments, the first stopper and the second stopper are respectively used to place the first probe and the second probe on the guide plate.
[0008] In some embodiments, the probe head structure further includes a second probe, the second probe passing through a third through-hole among the plurality of through-holes, and a distance from the top of the needle bridge to the guide plate is less than or equal to a distance from the top of the second probe to the guide plate.
[0009] In some embodiments, in a top view, the needle bridge is not in electrical contact with the second probe.
[0010] In some embodiments, the needle bridge has a rectangular profile in top view.
[0011] In some embodiments, the probe head structure further includes a third probe. The third probe passes through a fourth through-hole among the plurality of through-holes. In a top view, the fourth through-hole is disposed between the first through-hole and the second through-hole, and the needle bridge does not overlap with the third probe.
[0012] In some embodiments, the angle of the turning point where the needle bridge is connected to the first head is an obtuse angle.
[0013] In some embodiments, the first probe further comprises an insulating layer, wherein the insulating layer covers the needle bridge.
[0014] In some embodiments, the first probe is a monomeric structure.
[0015] Another embodiment of the present disclosure provides a probe head structure comprising a guide plate having a plurality of perforations and a first probe. The first probe comprises a first needle arm, a second needle arm, a first head, a second head, and a needle bridge. The first needle arm passes through a first perforation among the plurality of perforations and is disposed below the guide plate. The second needle arm passes through a second perforation among the plurality of perforations and is disposed below the guide plate. The first head is disposed on the first needle arm and is located above the guide plate. The second head is disposed on the second needle arm and is located above the guide plate. The needle bridge has a first end and a second end. The first end connects the first needle arm and the first head, and the second end connects the second needle arm and the second head, so that the first needle arm and the second needle arm pass through a needle bridge-shaped electrical signal path. The needle bridge is used to fix the first probe on the guide plate. The first needle arm is used to receive a signal from a first contact pad of the object to be tested. The signal passes through the first needle arm, the first head, the needle bridge, the second head, and the second needle arm in sequence to the second contact pad of the object to be tested.
[0016] In some embodiments, the needle bridge has a rectangular profile in top view.
[0017] In some embodiments, the probe head structure further includes a second probe. The second probe passes through a third through-hole among the plurality of through-holes. In a top view, the third through-hole is disposed between the first through-hole and the second through-hole, and the needle bridge does not overlap with the second probe.
[0018] In some embodiments, a distance from the bottom of the needle bridge to the guide plate is smaller than a distance from the top of the second probe to the guide plate.
[0019] In some embodiments, the angle of the turning point where the first end of the needle bridge is connected to the first needle arm is an obtuse angle.
[0020] In some embodiments, the first probe further includes an insulating layer, which covers the sidewalls of the first needle arm, the sidewalls of the second needle arm, and the needle bridge.
[0021] In some embodiments, the first probe is a monomeric structure.
[0022] Accordingly, due to the probe head structure disclosed herein, the impedance of the signal loop can be reduced during testing, and for impedance-sensitive signals, the test accuracy can be effectively improved.
[0023] The above has been a fairly broad overview of the technical features and advantages of the present disclosure, so that the detailed description of the present disclosure below can be better understood. Other technical features and advantages that constitute the subject matter of the claims of the present disclosure will be described below. It should be understood by those skilled in the art to which the present disclosure belongs that the concepts and specific embodiments disclosed below can be readily utilized to modify or design other structures or processes to achieve the same purposes as those of the present disclosure. It should also be understood by those skilled in the art to which the present disclosure belongs that such equivalent constructions cannot depart from the spirit and scope of the present disclosure as defined by the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The disclosure will be more fully understood with reference to the drawings when considered in conjunction with the following description. Like elements in the drawings are referred to by like numbers.
[0025] Figure 1 is a schematic diagram of a test system of some embodiments of the present disclosure.
[0026] Figure 2 is a schematic diagram of a probe head structure of some embodiments of the present disclosure.
[0027] Figure 3A and Figure 3B is a schematic diagram of a probe of some embodiments of the present disclosure.
[0028] Figure 4 is a schematic diagram of a probe of some embodiments of the present disclosure.
[0029] Figure 5 is a top view of a probe head structure of some embodiments of the present disclosure.
[0030] Figure 6 is a schematic diagram of different probe head structures of other embodiments of the present disclosure.
[0031] Figure 7A and Figure 7B is a schematic diagram of a probe of some embodiments of the present disclosure.
[0032] Figure 8 is a schematic diagram of a probe of some embodiments of the present disclosure.
[0033] In the drawings, the following drawing reference numbers have the following meanings:
[0034] 1: test system
[0035] 10: probe card
[0036] 100, 400: probe head structure
[0037] 110: guide plate
[0038] 120, 130, 140, 420: probe
[0039] 121, 122, 131, 141, 421, 422: needle arm
[0040] 121P, 122P, 131P, 421P, 422P: contact end
[0041] 123, 124, 133, 143, 423, 424: head
[0042] 123T, 127T, 133T, 423T, 424T: top
[0043] 125, 126, 135, 145: stop
[0044] 127, 427: needle bridge
[0045] 127B: bottom
[0046] 128, 138, 428: insulating layer
[0047] 200: circuit board
[0048] 300: substrate
[0049] 427a: first end
[0050] 427b: second end
[0051] DUT: device under test
[0052] L1: length
[0053] L2, L3, L4: distance
[0054] PD1, PD2, PD3, PD4: contact pad
[0055] S1, S2, S3: signal
[0056] TH, TH1, TH2, TH3, TH4: through hole
[0057] W1, W2, W3, W4: turn
[0058] X, Y, Z: direction
[0059] EM1, EM2, EM3, EM4: dashed box DETAILED DESCRIPTION
[0060] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description, serve to explain the principles of the disclosure. In the drawings:
[0061] "An embodiment," "one embodiment," "an example embodiment," "some embodiments," "another embodiment," "one implementation," "an implementation," "some implementations," "another implementation," and the like, refer to particular embodiments of the present disclosure that can include a particular feature, structure, or characteristic, but every embodiment can not necessarily include the particular feature, structure, or characteristic. Furthermore, repeated use of the phrases "in one embodiment" or "in an embodiment" does not necessarily refer to the same embodiment, although it can. In addition, referencing a "socket assembly" in this specification refers primarily to socket assemblies used in semiconductor testing for die testing.
[0062] In order to make the present disclosure fully understandable, the following description provides detailed steps and structures. Obviously, the implementation of the present disclosure does not limit the specific details known to those skilled in the art. In addition, known structures and steps are not described in detail again to avoid unnecessarily limiting the present disclosure. The preferred embodiments of the present disclosure are described in detail below. However, in addition to the detailed description, the present disclosure can also be widely implemented in other embodiments. The scope of the present disclosure is not limited to the content of the detailed description, but is defined by the claims.
[0063] It should be understood that the following disclosure provides many different embodiments or examples for implementing the different features of the present disclosure. Specific embodiments or examples of components and arrangements are described below to simplify the present disclosure. Of course, the plurality is merely an example and is not intended to be limiting. For example, the dimensions of the components are not limited to the disclosed ranges or values, but may depend on the process conditions and / or the desired properties of the device. In addition, the following description of forming a first feature "above" or "on" a second feature may include embodiments in which the first and second features are formed to be in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, thereby making it possible for the first and second features not to be in direct contact. For the sake of brevity and clarity, various features may be drawn at different scales. In the accompanying drawings, some layers / features may be omitted for simplicity.
[0064] Furthermore, for ease of description, spatially relative terms such as "beneath," "below," "lower," "above," and "upper" may be used herein to describe the relationship of one component or feature to another component or feature as illustrated in the figures. These spatially relative terms are intended to encompass different orientations of a component in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein should be interpreted accordingly.
[0065] Figure 1 FIG1 is a schematic diagram of a test system 1 according to some embodiments of the present disclosure. The test system 1 performs electrical testing on a DUT using a probe card 10. In some embodiments, the DUT may be a wafer-level or chip-level integrated circuit.
[0066] Since the sizes of the components in the test system 1 vary widely, for ease of description, many elements are not shown in full scale.
[0067] The probe card 10 performs electrical testing by contacting contact pads on a device under test (DUT) with the probe head structure 100. The probe card includes a circuit board 200, a substrate 300, and the probe head structure 100. The probe head structure 100 is disposed on the substrate 300. In some embodiments, the probe head structure 100 is implemented with vertical probes. In some embodiments, the substrate 300 is a ceramic substrate that serves as a mount for the probe head structure 100. The substrate 300 is disposed on the circuit board 200 to serve as an intermediary connection for electrical signals between the probe head structure 100 and the circuit board 200.
[0068] In some embodiments, the contact pad PD1 and the contact pad PD2 are a transmit terminal and a receive terminal, respectively, of the DUT. The probe card 10 is configured to receive a signal S1 from the contact pad PD1 and to loopback the signal S1 to the contact pad PD2. To reduce impedance between the contact pad PD1 and the contact pad PD2, the probe card 10 uses only the probe head structure 100 to form a loopback for the signal S1. In other words, the signal S1 is looped back to the contact pad PD2 without passing through the substrate 300 and the circuit board 200 of the probe card 10.
[0069] In some embodiments, the probe card 10 is configured to transmit a signal S2 from a tester (not shown) to the contact pad PD3 for operation of the DUT. In some embodiments, the probe card 10 is configured to receive a signal S3 from the contact pad PD4 and to transmit the signal S3 through the substrate 300 and the circuit board 200 to the tester for analysis.
[0070] Figure 2 FIG. 1 is a schematic diagram of a probe head structure 100 according to some embodiments of the present disclosure. The probe head structure 100 includes a guide plate 110, probes 120, probes 130, and probes 140. It should be understood that, Figure 2 The number of the probes 120, the probes 130, and the probes 140 shown is merely illustrative, and the present disclosure is not limited thereto. Various numbers of the probes 120, the probes 130, and the probes 140 are within the consideration and scope of the present disclosure.
[0071] The guide plate 110 has a plurality of through holes. In some embodiments, the through holes are uniformly distributed on the guide plate 110. As shown, Figure 2 The guide plate 110 includes a through hole TH1, a through hole TH2, a through hole TH3, and a through hole TH4. The probes 120 are disposed on the guide plate 110 through the through hole TH1 and the through hole TH2. The probes 130 and the probes 140 are disposed on the guide plate 110 through the through hole TH3 and the through hole TH4, respectively.
[0072] As shown, Figure 2As shown, probe 120 is arch-shaped with an opening, wherein the arch-shaped opening faces the -Z direction. Probe 120 does not overlap with other probes, that is, probe 120 is arranged to bypass other probes. In some embodiments, probe 120 is not in electrical contact with other probes. In some embodiments, probe 120 does not touch other probes.
[0073] Figure 3A and Figure 3B Schematic diagram of probe 120 according to some embodiments of the present disclosure. Probe 120 includes a needle arm 121, a needle arm 122, a head 123, a head 124, a stopper 125, a stopper 126, and a needle bridge 127. Needle arms 121 and 122 extend through through-hole TH1 and through-hole TH2, respectively, and are positioned below guide plate 110. Stoppers 125 and 126 are positioned above guide plate 110. Stopper 125 is positioned between needle arm 121 and head 123, while stopper 126 is positioned between needle arm 122 and head 124. Heads 123 and 124 are positioned above guide plate 110, above stoppers 125 and 126, respectively.
[0074] In some embodiments, the needle arm 121 and the head 123 have substantially the same width along the X direction. The stopper 125 connects the needle arm 121 and the head 123, wherein the stopper 125 has a greater width in the X direction than the needle arm 121 and the head 123. Figure 3A and Figure 3B In the cross section shown, the stoppers 125, 126 have a convex triangular profile. In other embodiments, the stoppers 125, 126 have other convex profiles, such as a trapezoidal or rectangular profile.
[0075] In some embodiments, the structure formed by the needle arm 121, the head 123 and the stopper 125 is the same as the structure formed by the needle arm 122, the head 124 and the stopper 126, and will not be repeated here.
[0076] The needle bridge 127 is provided between the head 123 and the head 124 and directly connects the head 123 and the head 124. Figure 3A and Figure 3B As shown, the angle of the turning point W1 where the needle bridge 127 connects to the head 123 is an obtuse angle, and the angle of the turning point W2 where the needle bridge 127 connects to the head 123 is an obtuse angle. In some embodiments, the angle of the turning point W1 is substantially the same as the angle of the turning point W2.
[0077] like Figure 3A As shown, in some embodiments, the top 123T of the head 123 is higher than the top 127T of the needle bridge 127 in the Z direction. That is, the length L1 is greater than 0. Please also refer to Figure 2, the distances from the top of each probe 120, 130, 140 to the guide plate 110 are substantially equal. When the length L1 is greater than 0, the distance L4 from the top of the needle bridge 127 of the probe 120 to the guide plate 110 is less than the distance L2 from the top of the probe 130 to the guide plate 110. Figure 3B As shown, in some embodiments, the top 123T of the head 123 is coplanar with the top 127T of the needle bridge 127 in the Z direction, that is, the length L1 is equal to 0. When the length L1 is equal to 0, the distance L4 from the top of the needle bridge 127 of the probe 120 to the guide plate 110 is equal to the distance L2 from the top of the probe 130 to the guide plate 110. The needle bridge 127 itself has a thickness, so the distance from the bottom 127B of the needle bridge 127 to the guide plate 110 is less than the distance L2 from the top of the probe 130 to the guide plate 110.
[0078] Please refer to Figure 1 In one embodiment, the needle arm 122 is in electrical contact with the contact pad PD1 (the transmitting end of the device under test (DUT), while the needle arm 121 is in electrical contact with the contact pad PD2 (the input end of the device under test (DUT)). In this embodiment, the needle arm 122 of the probe card 10 is used to receive the signal S1 from the contact pad PD1. The signal S1 is sequentially transmitted through the needle arm 122, the head 123, the needle bridge 127, and the needle arm 121 to return the signal S1 to the contact pad PD2. The probe card 10 only uses the probe head structure 100 to form a loop to return the signal S1. In other words, the signal S1 is returned to the contact pad PD2 without passing through the substrate 300 and the circuit board 200 of the probe card 10. In some embodiments, the guide plate 110 is made of an insulating material. Therefore, when the needle arm 121 touches the guide plate 110 in the through hole TH1, it does not electrically connect to the guide plate 110. In other embodiments, the guide plate 110 includes insulating material and is disposed at the through holes TH1 to TH4 so that when the needle arm 121 touches the guide plate 110 in the through hole TH1 , it does not establish an electrical connection with the guide plate 110 .
[0079] Figure 4 1 is a schematic diagram of a probe 130 according to some embodiments of the present disclosure. The probe 130 includes a needle arm 131, a head 133, and a stopper 135. The stopper 135 is disposed on the needle arm 131. The head 133 is disposed on the stopper 135.
[0080] In some embodiments, needle arm 131 is substantially the same as needle arm 121, and stop 135 is substantially the same as stop 125. Head 133 has substantially the same width in the X direction as head 123. Head 133 has substantially the same length in the Z direction as head 123.
[0081] In some embodiments, the probe 130 is the same as the probe 140 and is not described again herein.
[0082] In some embodiments, the needle arm 121, the needle arm 122, the head 123, the head 124, the stop 125, the stop 126, and the needle bridge 127 of the probe 120 are made of the same conductive material. In some embodiments, the probes 120, 130, and 140 are made of the same conductive material.
[0083] In some embodiments, the needle arm 121, the needle arm 122, the head 123, the head 124, the stop 125, the stop 126, and the needle bridge 127 of the probe 120 are made of the same material. In some embodiments, the probes 120, 130, and 140 are made of the same material.
[0084] In some embodiments, the needle arm 121, the needle arm 122, the head 123, the head 124, the stop 125, the stop 126, and the needle bridge 127 of the probe 120 are made of the same material, and the probe 120 is a monolithic structure. In some embodiments, each of the probes 120, 130, and 140 is a monolithic structure. In some embodiments, the probes 120, 130, and 140 are made by a micro electro mechanical system (MEMS) process or a laser cutting process.
[0085] In some embodiments, the probe 120 is used to transmit Figure 1 the signal S1. Specifically, the needle arm 121 is used to contact the contact pad PD1, and the needle arm 122 is used to contact the contact pad PD2. When the signal S1 passes through the electrical signal path composed of the needle arm 121, the stop 125, the head 123, the needle bridge 127, the head 124, the stop 126, and the needle arm 122 in sequence, because the probe 120 is a monolithic structure, there is no contact impedance caused by different materials or different structures in the probe 120. Furthermore, when the turning points W1 and W2 are obtuse angles, the impedance generated when the signal S1 passes from the head 123 to the needle bridge 127 and from the needle bridge 127 to the head 124 is also low. Based on the above, the equivalent impedance experienced by the signal S1 can be reduced, which is beneficial to the electrical test of the device under test DUT.
[0086] Please refer to Figure 2 When the probe head structure 100 approaches the device under test DUT, the guide plate 110 is used to fix the probes 120, 130, and 140, and limit the positions of the probes 120, 130, and 140 in the Z direction. Specifically, when the probe head structure 100 contacts the device under test DUT, the distance from the tip of each of the probes 120, 130, and 140 to the guide plate 110 is equal.
[0087] With the probe 120 as an example, when the probe 120 moves in the -Z direction, the guide plate 110 does not move at first. At this time, in the Z direction, the needle arm 121 and the needle arm 122 of the probe 120 can move relative to the guide plate 110. When the probe 120 moves in the -Z direction by a certain distance, the stop portion 125 contacts the guide plate 110 with the stop portion 135, so that the probe 120 has to move the guide plate 110 if it continues to move in the -Z direction.
[0088] In some embodiments, when the probes 120, 130, 140 move, they move against the probe head structure 100 by the substrate 300 above. Therefore, the head 123, the head 124, and the head 133 contact the substrate 300. However, because the probe 120 forms a loop by itself, the head 123 and the head 124 are in contact with the substrate 300 but are insulated from each other. The probe 130 needs to transmit signals to the substrate 300, so the head 133 is electrically connected to the substrate 300.
[0089] Figure 5 is a top view of the probe head structure 100 of some embodiments of the present disclosure. In addition to the aforementioned through holes TH1-TH4, the guide plate 110 also includes a plurality of through holes TH. In some embodiments, the probe head structure 100 also includes a plurality of probes (not shown) disposed in the plurality of through holes TH. For the sake of simplicity and ease of illustration, Figure 5 The probes 130, 140 are omitted, and only the probe 120 is shown in the top view of various embodiments.
[0090] In the embodiment shown in the dashed box EM1 and the dashed box EM2, the needle bridge 127 connects the head 123 and the head 124 in the shortest path in the top view and does not cross any probe. In some embodiments, the needle bridge 127 has a rectangular profile in the top view.
[0091] In the embodiment shown in the dashed box EM3, the needle bridge 127 bypasses another through hole TH between the through hole TH1 and the through hole TH2 in the top view and has straight edges and right-angle turns. In some embodiments, the needle bridge 127 has an obtuse-angle turn in the top view.
[0092] In the embodiment shown in the dashed box EM4, the needle bridge 127 bypasses another through hole TH between the through hole TH1 and the through hole TH2 in the top view and has an arc-shaped edge.
[0093] Figure 6 is a schematic diagram of a probe head structure 400 of other embodiments of the present disclosure. In some embodiments, the probe card 10 includes the circuit board 200, the substrate 300, and the probe head structure 400. That is, the probe head structure of the probe card 10 can use the probe head structure 100 or the probe head structure 400.
[0094] The probe head structure 400 is similar to the probe head structure 100. The probe head structure 400 includes the guide plate 110, the probes 420, the probes 130 (not shown for simplicity of illustration), and the probes 140. The guide plate 110, the probes 130, and the probes 140 of the probe head structure 400 are the same as the guide plate 110, the probes 130, and the probes 140 of the probe head structure 100, and are not described again.
[0095] The probes 420 do not have the stops 125 and 126 compared to the probes 120. The probes 420 include the needle arms 421, the needle arms 421, the heads 423, the heads 423, and the needle bridges 427. The needle arms 421 connect to the heads 423, and the needle arms 422 directly connect to the heads 424. The needle bridges 427 have a first end 427a connected at the junction of the needle arm 421 and the head 423, and a second end 427b connected at the junction of the needle arm 422 and the head 424. The angle of the bend W3 where the needle bridge 427 connects to the needle arm 421 is an obtuse angle, and the angle of the bend W4 where the needle bridge 427 connects to the needle arm 422 is an obtuse angle. In some embodiments, the angle of the bend W3 is substantially the same as the angle of the bend W4.
[0096] In some embodiments, the probes 420 are monolithic structures.
[0097] In some embodiments, the probes 420 are used to transmit Figure 1 The signal S1 is shown. Specifically, the needle arm 421 is used to contact the contact pad PD1, and the needle arm 422 is used to contact the contact pad PD2. When the signal S1 passes through the electrical signal path composed of the needle arm 421, the needle bridge 427, and the needle arm 422 in sequence, because the probes 420 are monolithic structures, there is no contact impedance within the probes 420 due to different materials or different structures. Furthermore, when the bends W3 and W4 are obtuse angles, the impedance generated when the signal S1 passes from the needle arm 421 to the needle bridge 427 and from the needle bridge 427 to the needle arm 422 is also low. Based on the above, the equivalent impedance experienced by the signal S1 can be reduced, which is beneficial for electrical testing of the DUT.
[0098] In some prior art, when a probe card is used to loop an output signal generated by a DUT back to the DUT, a loop is formed by the probe card, a substrate, and / or a circuit board, etc. to return the signal to the DUT. Such a loop includes multiple heterogeneous contact points, and the signal path is relatively long, so the equivalent capacitance resistance (RC) experienced by the signal is not good, especially for high-frequency signals that are more sensitive to RC response. Therefore, the accuracy of the test is affected by the large equivalent RC.
[0099] Compared to the prior art, the present disclosure only utilizes the body of the probe 120 / 420 as a loop, reduces the contact points of heterogeneous contacts, and reduces the path length of the loop, thereby improving the accuracy of the test.
[0100] Figure 7A is a schematic diagram of a probe 120 of some embodiments of the present disclosure. In some embodiments, the probe 120 further comprises an insulating layer 128. The insulating layer 128 covers the sidewalls of the needle arms 121 and 122, the sidewalls of the stops 125 and 126, and the sidewalls of the heads 123 and 124. The insulating layer 128 further covers the needle bridge 127. The insulating layer 128 is used to isolate the probe 120 from external electrical contact, and only exposes the contact end 121P of the needle arm 121, the contact end 122P of the needle arm 122, the top 123T of the head 123, and the top 124T of the head 124. In some embodiments, the insulating layer 128 only covers the needle bridge 127.
[0101] Figure 7B is a schematic diagram of a probe 420 of some embodiments of the present disclosure. In some embodiments, the probe 420 further comprises an insulating layer 428. The insulating layer 428 covers the sidewalls of the needle arms 421 and 422, and the sidewalls of the heads 423 and 424. The insulating layer 128 further covers the needle bridge 427. The insulating layer 428 is used to isolate the probe 420 from external electrical contact, and only exposes the contact end 421P of the needle arm 421, the contact end 422P of the needle arm 422, the top 423T of the head 423, and the top 424T of the head 424.
[0102] Figure 8 is a schematic diagram of the probes 130 and 140 of some embodiments of the present disclosure. In some embodiments, at least one of the probes 130 and 140 further comprises an insulating layer. The insulating layer is disposed on the probes 130 and 140 in a similar manner. For the sake of simplicity of the drawing, Figure 8 only the probe 130 is shown.
[0103] The probe 130 further comprises an insulating layer 138. The insulating layer 138 covers the sidewalls of the needle arm 131, the sidewalls of the stop 135, and the sidewalls of the head 133. The insulating layer 138 is used to isolate the probe 130 from external electrical contact, and only exposes the contact end 131P of the needle arm 131 and the top 133T of the head 133.
[0104] In summary, the test system of the embodiments of the present disclosure utilizes a shorter path to form a signal loop and reduces the heterogeneous contact points in the loop, so that the equivalent RC of the signal loop is reduced and the accuracy of the test is improved.
[0105] While the disclosure and its advantages have been disclosed in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. For example, many of the techniques described can be performed with different hardware and software configurations, or in conjunction with each other in a manner not specifically described herein.
[0106] Further, the scope of the disclosure is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein can be utilized according to the present disclosure. Accordingly, the appended claims are intended to cover all such processes, machines, manufacture, compositions of matter, means, methods, or steps.
Claims
1. A probe head structure, characterized in that: Include: a guide plate having a plurality of through holes; and A first probe comprising: a first needle arm passing through a first through-hole among the plurality of through-holes and disposed below the guide plate; a second needle arm passing through a second through-hole among the plurality of through-holes and disposed below the guide plate; a first head portion, disposed on the first needle arm and located above the guide plate; a second head portion, disposed on the second needle arm and located above the guide plate; a first stopper, disposed between the first head and the first needle arm and located above the guide plate; a second stopper, disposed between the second head and the second needle arm and located above the guide plate; as well as a needle bridge connecting the first head and the second head, The first needle arm and the second needle arm form an electrical signal path through the needle bridge, wherein the first needle arm is used to receive a signal from a first contact pad of an object to be tested, and the signal passes through the first needle arm, the first head, the needle bridge, the second head and the second needle arm in sequence to a second contact pad of the object to be tested.
2. The probe head structure according to claim 1, wherein: The first stopper and the second stopper are used to respectively arrange the first probe and the second probe on the guide plate.
3. The probe head structure according to claim 1, wherein: Also includes: a second probe passing through a third through-hole among the plurality of through-holes, A distance from a top of the needle bridge to the guide plate is less than or equal to a distance from a top of the second probe to the guide plate.
4. The probe head structure according to claim 3, wherein: In a top view, the needle bridge is not in electrical contact with the second probe.
5. The probe head structure according to claim 1, wherein: In a top view, the needle bridge has a rectangular outline.
6. The probe head structure according to claim 1, wherein: Also includes: a third probe passing through a fourth through-hole among the plurality of through-holes; In a top view, the fourth through-hole is disposed between the first through-hole and the second through-hole, and the needle bridge and the third probe do not overlap.
7. The probe head structure according to claim 1, wherein: An angle of a turning point where the needle bridge is connected to the first head is an obtuse angle.
8. The probe head structure according to claim 1, wherein: The first probe further comprises: An insulating layer covers the needle bridge.
9. The probe head structure according to claim 1, wherein: The first probe is a monomer structure.
10. A probe head structure, characterized in that: Include: a guide plate having a plurality of through holes; and A first probe comprising: a first needle arm passing through a first through-hole among the plurality of through-holes and disposed below the guide plate; a second needle arm passing through a second through-hole among the plurality of through-holes and disposed below the guide plate; a first head portion, disposed on the first needle arm and located above the guide plate; a second head portion, disposed on the second needle arm and located above the guide plate; and a needle bridge having a first end and a second end, wherein the first end connects the first needle arm and the first head, and the second end connects the second needle arm and the second head, so that the first needle arm and the second needle arm pass through the needle bridge-shaped electrical signal path, wherein the needle bridge is used to fix the first probe on the guide plate, The first needle arm is used to receive a signal from a first contact pad of a test object, and the signal passes through the first needle arm, the first head, the needle bridge, the second head and the second needle arm in sequence to a second contact pad of the test object.
11. The probe head structure according to claim 10, wherein: In a top view, the needle bridge has a rectangular outline.
12. The probe head structure according to claim 10, wherein: Also includes: a second probe passing through a third through-hole among the plurality of through-holes, In a top view, the third through-hole is disposed between the first through-hole and the second through-hole, and the needle bridge and the second probe do not overlap.
13. The probe head structure according to claim 12, wherein: A distance from a bottom of the needle bridge to the guide plate is smaller than a distance from a top of the second probe to the guide plate.
14. The probe head structure according to claim 10, wherein: An angle at a turning point where the first end of the needle bridge is connected to the first needle arm is an obtuse angle.
15. The probe head structure according to claim 10, wherein: The first probe further comprises: An insulating layer covers the side wall of the first needle arm, the side wall of the second needle arm and the needle bridge.
16. The probe head structure according to claim 10, wherein: The first probe has a monomer structure.