Probe card with pluggable substrate
By using a pluggable substrate design and flexible contacts, the high-cost connection and maintenance challenges between the substrate and the PCB are solved, enabling low-cost, reliable signal transmission and efficient maintenance, and ensuring the testing accuracy of the probe card.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-28
- Publication Date
- 2026-03-06
AI Technical Summary
The existing BGA reflow soldering connection method between the substrate and the PCB board is costly, difficult to repair, and the high temperature soldering can easily cause substrate deformation, affecting the flatness of the probe and the stability of the test signal.
The design employs a pluggable substrate, which allows for detachable connection between the substrate and the PCB board. It utilizes elastic contacts to achieve conductivity between the pins and the PCB pads, eliminating the need for traditional BGA reflow soldering connections, reducing production costs, and simplifying the maintenance process.
It reduces production costs, simplifies the maintenance process, avoids substrate scrap and deformation, ensures good contact between probes and chip pads, and guarantees stable transmission and accuracy of test signals.
Smart Images
Figure CN223977273U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of chip testing equipment technology, specifically to a probe card with a pluggable substrate. Background Technology
[0002] In the field of semiconductor testing, probe cards play an indispensable and crucial role. Their core function is to accurately transmit signals from the testing equipment to the chip under test. Probe cards mainly consist of three parts: a PCB (printed circuit board), a substrate, and probes.
[0003] The PCB board carries the substrate and probes, providing the electrical connection foundation for the entire system. Probes are mounted on the substrate and electrically connected to the internal PCB circuitry via the substrate's adapter circuitry. The substrate acts as an adapter layer, converting high-density probe connections to connections suitable for lower-density PCB circuitry using its internal adapter circuitry, thus meeting the high-density layout requirements of the probes. During actual chip testing, when the probes contact the chip, the signal is first transmitted to the substrate. The substrate's internal adapter circuitry then converts the signal transmission spacing before transmitting the signal through the PCB circuitry to the testing equipment.
[0004] In electronic manufacturing, the internal circuits of the substrate and PCB are typically connected using BGA reflow soldering. Both the substrate and PCB have pads corresponding to the BGA reflow soldering. However, BGA reflow soldering requires high-precision equipment, resulting in high production costs. Furthermore, once soldering is complete, rework is required, and removing the substrate is extremely difficult. Even slight mistakes during operation can easily damage the PCBA (Printed Circuit Board Assembly), severely impacting subsequent product use and yield. Simultaneously, the substrate must be scrapped. The side of the substrate that connects to the probe tip must align with the spacing and position of the test pins on the chip on the test wafer, making manufacturing extremely difficult and costly, drastically increasing overall costs. Additionally, the high-temperature environment during reflow soldering can easily deform the substrate. This deformation further affects the flatness of the probe test end, leading to poor contact between the probe and the chip pads during chip testing. This results in unstable test signal transmission, significant data deviation, and an inability to accurately reflect the chip's true performance. Utility Model Content
[0005] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application provides a probe card with a pluggable substrate, which solves the problems of high cost, difficult maintenance, and easy impact on probe flatness caused by using BGA reflow soldering to connect the substrate and PCB board in the prior art.
[0006] The objective of this application can be achieved through the following technical solutions:
[0007] This application provides a probe card with a pluggable substrate. The probe card includes a substrate, a PCB board, pins, a socket, and a resilient contact.
[0008] The substrate and the PCB are detachably connected. The pins are located on the side of the substrate near the PCB and are matched and connected to the internal adapter circuit of the substrate.
[0009] The socket is located on the side of the PCB board near the substrate. The socket has holes that match the position and number of pins, and each hole has a resilient contact.
[0010] The resilient contact is configured to make the pin connected to the corresponding PCB pad when the pin is inserted into the corresponding socket.
[0011] Optionally, the resilient contact element has a tubular structure and is coaxially arranged with the socket, including the following from top to bottom:
[0012] The top opening section has an inner diameter larger than the pin diameter to guide pin insertion.
[0013] The elastic contraction section has an inner diameter smaller than the pin diameter, forming a radial elastic clamping on the pin;
[0014] The bottom fixing section is electrically connected to the PCB pads.
[0015] Optionally, the socket has a stepped surface, with the top of the elastic contact abutting the stepped surface and the bottom of the elastic contact abutting the PCB pad.
[0016] Optionally, the inner wall of the elastic contraction section has an arc-shaped protrusion structure.
[0017] Optionally, the resilient contact element is made of beryllium copper alloy; and / or,
[0018] The sockets are made of ceramic or engineering plastic.
[0019] Optionally, the socket has a bending strength greater than 300 MPa; and / or,
[0020] The flatness of the contact surface between the socket and the substrate is less than 25μm.
[0021] Optionally, the socket is surrounded by a metal frame, which is fixed to the PCB board by bolts.
[0022] Optionally, the pins are arranged in an array on the substrate surface.
[0023] Optionally, the substrate can be a multilayer organic substrate or a ceramic substrate.
[0024] Optionally, the substrate and the PCB are respectively provided with a first positioning part and a second positioning part that match each other, and the first positioning part and the second positioning part cooperate to align the substrate and the PCB.
[0025] Beneficial effects:
[0026] By designing the substrate and PCB board with a detachable connection, the traditional BGA reflow soldering method is eliminated, reducing reliance on high-precision soldering equipment and cutting production costs. Subsequent rework or component replacement is simplified, avoiding substrate scrapping and PCBA damage during substrate removal, thus improving product yield. Simultaneously, flexible contacts ensure pin-to-PCB pad conductivity, reducing substrate deformation caused by high soldering temperatures, guaranteeing probe flatness, and ensuring good contact between the probe and chip pads. This results in stable test signal transmission and accurate reflection of the chip's true performance. Attached Figure Description
[0027] The present application will be further described below with reference to the accompanying drawings.
[0028] Figure 1 This is a schematic diagram of the overall structure of the probe card in one embodiment of this application;
[0029] Figure 2 This is an exploded view of a portion of the probe card structure in one embodiment of this application;
[0030] Figure 3 This is a top view of the socket in one embodiment of this application.
[0031] Explanation of reference numerals in the attached figures:
[0032] 10. Substrate; 11. PCB board; 12. Pin; 13. Socket; 14. Flexible contact; 141. Top opening section; 142. Flexible retractable section; 143. Bottom fixing section; 15. Socket; 16. Adapter circuit; 17. PCB circuit; 18. Probe; 19. PCB pad; 20. Metal frame; 21. Stepped surface. Detailed Implementation
[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0034] Please see Figure 1 and Figure 2As shown, in some embodiments, this application provides a probe card with a pluggable substrate. The probe card includes a substrate 10, a PCB board 11, pins 12, a socket 13, and elastic contacts 14. The substrate 10 is detachably connected to the PCB board 11. The pins 12 are disposed on the side of the substrate 10 near the PCB board 11 and are matched and connected to the internal adapter circuit 16 of the substrate 10. The socket 13 is disposed on the side of the PCB board 11 near the substrate 10. The socket 13 has holes 15 that match the position and number of the pins 12, and each hole 15 is provided with an elastic contact 14. The elastic contact 14 is configured to connect the pin 12 to the corresponding PCB pad 19 when the pin 12 is inserted into the corresponding hole 15.
[0035] In the overall architecture of the probe card, the substrate 10 plays a crucial role as an interconnection layer. Its meticulously designed internal interconnection circuit 16 is specifically designed based on the signal transmission requirements during chip testing. In chip testing scenarios, the probes 18 are arranged in a high-density configuration, while the PCB circuits 17 inside the PCB board 11 are arranged in a low-density configuration. The key function of the interconnection circuit 16 is to realize the electrical interconnection conversion between the two.
[0036] Specifically, the mounting positions of each component are as follows: Probe 18 is vertically mounted on the side of substrate 10 away from PCB board 11, responsible for contacting the chip and acquiring signals; pin 12 is vertically mounted on the side of substrate 10 closer to PCB board 11. To ensure stable signal transmission, pin 12 is securely fixed to the pads of substrate 10 by soldering. It is worth noting that the pads of substrate 10 correspond one-to-one with the internal transition circuit 16, which ensures that pin 12 and the internal transition circuit 16 of substrate 10 can be precisely matched and conduct, thus laying a solid foundation for stable signal transmission in the probe card.
[0037] PCB board 11 provides the electrical connection foundation for the entire probe card. Socket 13 is installed on the side of PCB board 11 closest to substrate 10 and is secured using mechanical methods (such as adhesive bonding or screw fixing). The distribution of sockets 15 on socket 13 is precisely designed according to the layout of pins 12 to ensure accurate mating. Flexible contact members 14 are installed inside sockets 15, and their positions are finely adjusted to ensure smooth contact and conduction when pins 12 are inserted.
[0038] By using a pluggable connection between the substrate 10 and the PCB board 11 via pins 12 and sockets 13, the traditional BGA reflow soldering connection method is eliminated, significantly reducing production costs, such as eliminating ball bonding, reflow soldering equipment, and stem il processes. It also simplifies the maintenance process; when the substrate 10 malfunctions, there is no need to completely disassemble the PCBA; only the substrate 10 needs to be pulled out for individual replacement or repair, avoiding the scrapping of the substrate 10 during maintenance and reducing maintenance risks and costs. Compared to the several days required for BGA processes, the pluggable structure allows for rapid assembly within one day, improving production efficiency. Furthermore, compared to traditional soldering methods, the pluggable connection reduces substrate 10 deformation caused by high soldering temperatures, thus ensuring the flatness of the probe 18 test end and ensuring good contact between the probe 18 and the chip pads, resulting in stable test signal transmission and accurately reflecting the chip's true performance.
[0039] Please see Figure 2 As shown, in one possible embodiment, the resilient contact 14 has a tubular structure and is coaxially arranged with the socket 15. The resilient contact 14 has a uniform wall thickness from top to bottom. The resilient contact 14 includes a top opening section 141, a resilient contraction section 142, and a bottom fixing section 143 from top to bottom. The inner diameter of the top opening section 141 is larger than the diameter of the pin 12, used to guide the pin 12 into place. The inner diameter of the resilient contraction section 142 is smaller than the diameter of the pin 12, forming a radial resilient clamping effect on the pin 12. The bottom fixing section 143 is electrically connected to the PCB pad 19.
[0040] Specifically, the inner diameter of the top opening section 141 is precisely designed to be slightly larger than the diameter of the pin 12. This larger inner diameter provides clear insertion guidance for the pin 12, allowing it to smoothly enter the elastic retraction section 142. This reduces the difficulty of pin 12 insertion and improves assembly efficiency and accuracy. The elastic retraction section 142 uses a special elastic material and design structure. When the pin 12 is inserted, its inner diameter, smaller than the pin 12's diameter, undergoes elastic deformation, applying a uniform clamping force radially to the pin 12. This ensures tight contact between the two, preventing loosening or poor contact, and further guaranteeing the reliability of test signal transmission. The inner diameter of the bottom fixing section 143 is approximately the same as that of the top opening section 141. The bottom fixing section 143 achieves a stable electrical connection with the PCB pad 19 through reliable connection methods such as welding and crimping, ensuring that the signal can be smoothly transmitted from the pin 12 to the PCB pad 19.
[0041] Please see Figure 2 As shown, in one possible implementation, the socket 15 has a stepped surface 21, the top end of the elastic contact 14 abuts against the stepped surface 21, and the bottom end of the elastic contact 14 abuts against the PCB pad 19.
[0042] Specifically, the socket 13 has a stepped hole 15, comprising a first hole segment and a second hole segment arranged from top to bottom. The first hole segment is located close to the substrate 10, and its diameter is smaller than that of the second hole segment. An elastic contact 14 is fitted into the second hole segment with a clearance fit, and the top end of the elastic contact 14 precisely abuts against the stepped surface 21. The stepped surface 21 presses against the elastic contact 14 to prevent axial displacement within the socket 15. The bottom end of the elastic contact 14 is tightly connected to the PCB pad 19 via welding, crimping, or other methods to ensure reliable electrical connection.
[0043] In one possible implementation, the inner wall of the elastic contraction section 142 has an arc-shaped protrusion structure.
[0044] Specifically, when pin 12 is inserted into the elastic contraction section 142, the arc-shaped protrusion contacts the surface of pin 12. Due to the characteristics of the arc-shaped structure, concentrated elastic pressure is generated at the contact point, further enhancing the clamping effect on pin 12. Furthermore, the arc-shaped protrusion structure increases the contact area and friction between the elastic contraction section 142 and pin 12, improving clamping stability. This structural design better adapts to changes in pin 12 under minute displacement or vibration conditions, maintaining good contact at all times, effectively improving the stability and reliability of test signal transmission, and reducing interference and loss during signal transmission.
[0045] In one possible implementation, the resilient contact 14 is made of beryllium copper alloy; and / or, the socket 13 is made of ceramic or engineering plastic.
[0046] Specifically, if the elastic contact 14 is made of beryllium copper alloy, beryllium copper alloy has excellent elastic properties, high strength, and good conductivity. During the manufacturing of the elastic contact 14, the beryllium copper alloy is processed into the required tubular structure through precision machining processes (such as stamping and machining). Due to the characteristics of beryllium copper alloy, it can produce stable and durable elastic deformation in the elastic contraction section 142, ensuring reliable clamping of the pin 12 and good electrical conductivity. At the same time, it also meets the requirements of the elastic contact 14 for sufficient mechanical strength, long fatigue life, and low resistivity.
[0047] If socket 13 is made of ceramic or high-strength engineering plastic, such as PEEEK or Photovell, ceramic and high-strength engineering plastic have advantages such as high insulation, high temperature resistance, and low coefficient of expansion.
[0048] When manufacturing the socket 13, a socket 13 structure with socket 15 is made by using ceramic forming technology (such as injection molding, isostatic pressing, etc.) or machining technology. The material properties can effectively avoid the impact of temperature changes, electrical interference and other factors on the socket 13 during use, and ensure the stable electrical performance of the probe card.
[0049] In one possible implementation, the bending strength of the socket 13 is greater than 300 MPa; and / or, the flatness of the contact surface between the socket 13 and the substrate 10 is less than 25 μm.
[0050] Specifically, by ensuring that the bending strength of the socket 13 is greater than 300 MPa, the higher bending strength prevents the socket 13 from bending and deforming under external forces (such as testing, assembly / disassembly, and impact). This avoids the socket 13 deforming and causing the socket 15 to shift position, affecting the fitting accuracy between the pin 12 and the socket 15, thereby ensuring the accuracy of test signal transmission. A smaller contact surface flatness plays a crucial role. After the socket 13 is assembled with the substrate 10, a smaller contact surface flatness prevents flatness issues of the socket 13 from being transmitted to the probes 18 mounted on the substrate 10. This avoids the flatness of the probes 18 being affected by poor flatness of the socket 13, thus preventing poor contact between some probes 18 and the chip pads, ensuring the stability and reliability of the entire test connection.
[0051] Please see Figure 3 As shown, in one possible implementation, the socket 13 is surrounded by a metal frame 20, which is fixed to the PCB board 11 by bolts.
[0052] Specifically, the metal frame 20 is made of a metal material with a certain strength and rigidity (such as aluminum alloy, stainless steel, etc.) and is formed through machining (such as stamping, cutting, welding, etc.). The shape and size of the metal frame 20 are designed according to the shape of the socket 13 to ensure that it can tightly surround the socket 13. Corresponding threaded holes are machined on the metal frame 20 and the PCB board 11, and the metal frame 20 is firmly fixed to the PCB board 11 with bolts. The metal frame 20 provides additional mechanical support and protection for the socket 13, enhances the installation stability of the socket 13 on the PCB board 11, and reduces the risk of the socket 13 loosening or shifting due to external forces.
[0053] In one possible implementation, the upper surface of the metal frame 20 is higher than the upper surface of the socket 13, and the metal frame 20 directly supports the substrate 10. The flatness of the upper surface of the metal frame 20 (i.e., the contact surface with the substrate 10) is controlled within 25 μm. Compared to using the surface of the socket 13 as the contact surface with the substrate 10, using the upper surface of the metal frame 20 as the contact surface has a significant advantage in terms of processing flatness. This is because the structural characteristics of the metal frame 20 make it easier to achieve the required flatness standard during processing, thereby providing more stable and reliable support for the substrate 10.
[0054] In one possible implementation, the pins 12 are arranged in an array on the surface of the substrate 10.
[0055] Specifically, during the manufacturing process of substrate 10, based on the chip testing requirements and signal transmission layout, semiconductor manufacturing processes such as photolithography and etching are used to precisely fabricate the mounting positions of pins 12 on the side of substrate 10 near PCB board 11. Pins 12 are arranged in a regular array pattern, such as a rectangular array or a circular array. The spacing and precision of the array are strictly designed and controlled according to the layout of PCB pads 19 and signal transmission requirements. When mounting pins 12, high-precision mounting equipment is used to accurately mount pins 12 onto substrate 10, ensuring their positional accuracy.
[0056] The array arrangement fully utilizes the surface space of the substrate 10, enabling high-density signal connections and meeting the requirements of multi-pin, high-precision signal transmission in chip testing. The regular array layout facilitates the corresponding connections of the PCB circuits 17 within the PCB board 11, improving assembly efficiency and accuracy. It also promotes orderly signal transmission, reduces interference between signals, and enhances the overall performance and testing accuracy of the probe card.
[0057] In one possible implementation, substrate 10 is a multilayer organic substrate or a ceramic substrate.
[0058] Specifically, if the substrate 10 is a multilayer organic substrate, it is typically formed by alternating layers of organic insulating materials (such as polyimide, BT resin, etc.) and conductive layers (such as copper foil). During the manufacturing process, the internal transition circuits 16 are fabricated using processes such as photolithography and etching. The layout of each layer of transition circuits 16 is carefully designed according to the signal transmission path and function. Multilayer organic substrates have good flexibility, low cost, and certain electrical performance advantages. If the substrate 10 is a ceramic substrate, it is made using ceramic materials (such as alumina, aluminum nitride, etc.) through processes such as casting, printing, and sintering. The internal transition circuits 16 of the ceramic substrate are fabricated using thick-film or thin-film processes. Ceramic substrates have characteristics such as high insulation, high thermal conductivity, high strength, and good dimensional stability.
[0059] The flexibility of the multilayer organic substrate allows it to better adapt to spatial layout requirements in some special applications, and its lower cost helps reduce the overall manufacturing cost of the probe card. The high insulation of the ceramic substrate can effectively reduce crosstalk between signals, and its high thermal conductivity helps dissipate heat, ensuring stable operation of the probe card for a long time. Its high strength and good dimensional stability ensure the structural integrity and accuracy of the substrate 10 in complex environments, providing a reliable foundation for signal transmission and improving the performance and reliability of the probe card.
[0060] In one possible implementation, the substrate 10 and the PCB board 11 are respectively provided with a first positioning part (not shown) and a second positioning part (not shown), which match each other. The first positioning part and the second positioning part cooperate to align the substrate 10 and the PCB board 11.
[0061] Specifically, during the manufacturing process of the substrate 10 and the PCB board 11, the first positioning part and the second positioning part are fabricated through machining, injection molding, and other processes. The shapes of the first positioning part and the second positioning part can be such that positioning holes and positioning pins mate, or positioning grooves and positioning protrusions mate. The dimensional and positional accuracy requirements of the positioning parts are extremely high. During assembly, the positioning parts on the substrate 10 and the PCB board 11 are accurately aligned. By inserting positioning pins into positioning holes and positioning protrusions into positioning grooves, the substrate 10 and the PCB board 11 are quickly and accurately aligned before subsequent connection operations are performed.
[0062] The cooperation between the first and second positioning parts can greatly improve the assembly efficiency and accuracy of the substrate 10 and the PCB board 11, ensuring that the pins 12 and the sockets 15 of the socket 13 can be precisely aligned, avoiding poor contact or signal transmission failures caused by misalignment. Precise alignment helps improve the production quality and consistency of the probe card, reduces the product defect rate caused by assembly problems, and improves the overall performance and reliability of the probe card.
[0063] The foregoing has provided a detailed description of one embodiment of this application, but the description is merely a preferred embodiment and should not be construed as limiting the scope of this application. All equivalent variations and modifications made within the scope of this application should still fall within the patent coverage of this application.
[0064] It should be noted that the terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Descriptions in this application regarding directions such as "left," "right," "left side," "right side," "upper part," "lower part," "top," and "bottom" are defined based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, not to indicate or imply that the described structure must be constructed and operated in a specific orientation, and therefore should not be construed as limiting this application. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0065] In the description of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
Claims
1. A probe card with a pluggable substrate, characterized in that, The probe card comprises a substrate, a PCB board, pins, sockets and elastic contact pieces; The substrate is detachably connected with the PCB board, the pins are arranged on the side of the substrate close to the PCB board and are matched with and conductive to the internal switching circuit of the substrate one by one; The sockets are arranged on the side of the PCB board close to the substrate, the sockets are provided with plug holes matched with the positions and numbers of the pins, and the elastic contact pieces are arranged in the plug holes; The elastic contact pieces are configured to conduct the pins and the corresponding PCB pads when the pins are inserted into the corresponding plug holes.
2. The probe card of claim 1, wherein, The elastic contact pieces are in a tubular structure and are coaxially arranged with the plug holes, comprising from top to bottom: A top opening section with an inner diameter larger than the diameter of the pins for guiding the insertion of the pins; An elastic contraction section with an inner diameter smaller than the diameter of the pins for forming radial elastic clamping of the pins; A bottom fixed section electrically connected with the PCB pad.
3. The probe card of claim 2, wherein, The plug holes are provided with a stepped surface, the top end of the elastic contact piece abuts against the stepped surface, and the bottom end of the elastic contact piece abuts against the PCB pad.
4. The probe card of claim 2, wherein, The inner wall of the elastic contraction section is in an arc convex structure.
5. The probe card of claim 1, wherein The elastic contact pieces are made of beryllium copper alloy; and / or, The sockets are made of ceramic material or engineering plastic.
6. The probe card of claim 1, wherein The bending strength of the sockets is greater than 300 MPa; and / or, The flatness of the contact surface of the sockets and the substrate is less than 25 μm.
7. The probe card of claim 1, wherein The sockets are provided with a metal frame, and the metal frame is fixed on the PCB board by bolts.
8. The probe card of claim 1, wherein, The pins are arranged in an array on the surface of the substrate.
9. The probe card of claim 1, wherein, The substrate is a multilayer organic substrate or a ceramic substrate.
10. The probe card according to any one of claims 1 to 9, wherein The substrate and the PCB board are respectively provided with first and second positioning parts matched with each other, and the first and second positioning parts are matched to align the substrate and the PCB board.