Test fixture
By designing test fixtures suitable for different types and sizes of RF chips, the high cost and low efficiency caused by the need for dedicated PCB fixtures for each chip in existing technologies have been solved, enabling rapid testing and efficient production.
Patent Information
- Application Number
- CN202520328321.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-27
- Publication Date
- 2025-12-02
- Estimated Expiration
- 2035-02-27
AI Technical Summary
Existing RF bare chip testing methods require the design of dedicated PCB fixtures for each chip, resulting in high costs and low efficiency.
Design a test fixture suitable for different types and sizes. By setting a first groove and a second mounting area, and combining an RF microstrip line with a ground groove, a rapid installation of bare chips and signal transmission can be achieved. This fixture is suitable for various chip types and sizes.
It improves testing efficiency, reduces design and manufacturing costs, and achieves versatility and operability for different chips.
Smart Images
Figure CN223624290U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of chip testing, and more specifically, to a test fixture. Background Technology
[0002] With the rapid development of radio frequency (RF) and microwave technology, various RF chips are widely used in aerospace, modern communication systems, and military fields. Testing RF chips is a crucial step in chip design, production, and application.
[0003] Radio frequency (RF) bare chip testing is particularly rigorous, and impedance matching is a fundamental requirement for RF design and testing; otherwise, it can cause severe signal emission and lead to test failure. Currently, the conventional method for RF bare chip testing is to create a prototype, typically a two-layer or multi-layer PCB made of RF materials. Solder mask windows are created on the PCB, and the bare chip is attached to these windows using conductive adhesive or solder pads. It is then bonded to the corresponding pads using gold wire bonding, with corresponding test pads exposed. This approach requires designing a specific prototype for each chip, resulting in high cost and low efficiency. Utility Model Content
[0004] This application provides a test fixture suitable for bare chips of different types and sizes, which can quickly test chip performance, has strong versatility and operability, saves design time and processing costs, and greatly improves testing efficiency.
[0005] The test fixture provided in this application adopts the following technical solution:
[0006] A test fixture, comprising:
[0007] The base is provided with a first groove, the first groove being provided with a first mounting area for mounting a bare chip and a second mounting area, the second mounting area surrounding the first mounting area.
[0008] A radio frequency microstrip line is disposed in the second mounting area, and the radio frequency microstrip line is connected to the bare chip by a bonding wire.
[0009] An RF connector is provided, corresponding to the RF microstrip line and passing through the base, wherein the RF microstrip line is connected to the RF connector.
[0010] Optionally, the first mounting area is provided with a second groove.
[0011] Optionally, the bottom of the first groove and the bottom of the second groove are provided with a gold plating layer, and the bare chip is fixedly disposed on the gold plating layer.
[0012] Optionally, it also includes a grounding post for leading out a ground wire, the grounding post being disposed on the base.
[0013] Optionally, an RF insulator is provided at the end of the RF microstrip line away from the bare chip. The RF insulator includes a first connection part, a second connection part, and a ground part. The first connection part is connected to the RF microstrip line, the second connection part is connected to the RF connector, and the ground part is connected to the ground post.
[0014] Optionally, the distance between the end of the radio frequency microstrip line closest to the bare chip and the bare chip is greater than or equal to 25 micrometers.
[0015] Optionally, multiple radio frequency microstrip lines and radio frequency connectors are provided, with multiple radio frequency microstrip lines located in the second mounting area and spaced apart, and multiple radio frequency connectors corresponding one-to-one with multiple radio frequency microstrip lines on the base.
[0016] Optionally, a plurality of the radio frequency microstrip lines are arranged in a centrally symmetrical manner around the first mounting area, and a plurality of the radio frequency connectors are arranged in a centrally symmetrical manner around the base.
[0017] Optionally, the base is an aluminum base, and the base is provided with a plurality of first mounting holes. Bolts pass through the first mounting holes for connection with an external copper base to enhance heat dissipation.
[0018] Optionally, the system also includes a cover plate for covering the first groove; the base is provided with a second mounting hole, and bolts pass through the cover plate and the second mounting hole to fix the cover plate to the base.
[0019] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:
[0020] When testing is required, a bare chip can be directly installed in the first mounting area. Based on the size of the bare chip, a suitable RF microstrip line is selected to match it. The RF microstrip line is then assembled in the second mounting area. During testing, the test signal is transmitted through the bare chip to the RF microstrip line, and then converted into a microwave signal by the RF connector before being output to the test instrument. This test fixture is suitable for testing different types and sizes of bare chips, enabling rapid chip performance testing. It has strong versatility and operability, saving design time and processing costs, and greatly improving testing efficiency. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings.
[0022] Figure 1 This is a schematic diagram of the overall structure of a test fixture disclosed in Embodiment 1 of this application;
[0023] Figure 2 This is a top view of a test fixture disclosed in Embodiment 1 of this application;
[0024] Figure 3 This is a top view of a test fixture disclosed in Embodiment 2 of this application;
[0025] Figure 4 This is a top view of a test fixture disclosed in Embodiment 3 of this application.
[0026] Explanation of reference numerals in the attached figures:
[0027] 1. Base; 11. First groove; 111. First mounting area; 112. Second mounting area; 12. Second groove; 13. Gold plating layer; 14. First mounting hole; 15. Second mounting hole; 2. RF microstrip line; 21. RF insulator; 3. RF connector; 4. Cover plate; 5. Power supply insulator; 6. Grounding post. Detailed Implementation
[0028] The present application will be further described in detail below with reference to the accompanying drawings.
[0029] This application provides a test fixture suitable for bare chips of different types and sizes, which can quickly test chip performance, has strong versatility and operability, saves design time and processing costs, and greatly improves testing efficiency.
[0030] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of them. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present application. Furthermore, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present application.
[0031] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0032] Please see Figure 1 and Figure 2 This is an embodiment of the test fixture disclosed in this application. The test fixture includes a base 1, an RF microstrip line 2, an RF connector 3, a power supply insulator 5, and a cover plate 4 (not shown in the figure). The radio frequency (RF) microstrip line 2 is a transmission line structure used to transmit high-frequency electromagnetic waves. During bare chip testing, the RF microstrip line 2 is installed on the base 1 and is responsible for transmitting high-frequency electrical signals from the test equipment to the chip under test (DUT) and returning a response signal. The RF connector 3 is installed corresponding to the RF microstrip line 2 and passes through the base 1. The RF microstrip line 2 is connected to the RF connector 3 to establish a stable electrical connection between the test equipment and the bare chip, ensuring that the signal source can be accurately coupled into the DUT and receive the output signal from the DUT. Multiple RF microstrip lines 2 and RF connectors 3 are provided. Multiple RF microstrip lines 2 are located in the second mounting area 112 and are spaced apart. Multiple RF connectors 3 are installed on the base 1 in a one-to-one correspondence with multiple RF microstrip lines 2. The power supply insulator 5 is installed on the base 1 and is connected to the power input terminal of the bare chip through a bonding wire. The bare chip is connected to an external power source through the power supply insulator 5 to achieve electrical isolation and stable power supply.
[0033] In this embodiment, the base 1 is an aluminum base 1. Using aluminum as the base 1 of the test fixture can quickly conduct the heat generated during the bare chip testing process to other areas of the base 1, avoiding local heat accumulation that could lead to uncontrolled temperature of the bare chip and thus ensuring test stability. Secondly, aluminum is lighter and cheaper to manufacture than metals such as copper, making it suitable for testing scenarios that require frequent movement or replacement, while also reducing the overall weight of the fixture and simplifying operation. Furthermore, to enhance the heat dissipation of the test fixture, the base 1 is provided with multiple first mounting holes 14. Bolts pass through the first mounting holes 14 to connect with the external copper base to enhance heat dissipation. By using the external copper base as an external heat dissipation structure, the heat dissipation of the test fixture can be further accelerated to ensure test stability.
[0034] The base 1 has a first groove 11, which has a first mounting area 111 and a second mounting area 112 for mounting a bare chip. The second mounting area 112 surrounds the first mounting area 111. An RF microstrip line 2 is disposed in the second mounting area 112, and the RF microstrip line 2 is connected to the bare chip via a bonding wire. When testing is required, the bare chip can be directly mounted to the first mounting area 111. Based on the size of the bare chip, a suitable RF microstrip line 2 is selected to match the chip, and then the RF microstrip line 2 is assembled into the second mounting area 112. During testing, the test signal is transmitted through the bare chip to the RF microstrip line 2, and then converted into a microwave signal by the RF connector 3 and output to the testing instrument. This test fixture is suitable for testing different types and sizes of bare chips, enabling rapid chip performance testing. It has strong versatility and operability, saves design time and processing costs, and greatly improves testing efficiency.
[0035] Please refer to Figure 2 In this embodiment, a radio frequency (RF) channel is provided on each of the left and right sides of the bare chip, and correspondingly, two RF microstrip lines 2 and two RF connectors 3 are provided. The two RF microstrip lines 2 are respectively located on the left and right sides of the bare chip, and the two RF connectors 3 are respectively located on the left and right sides of the base 1. The bare chip is assembled onto the second mounting area 112 using conductive adhesive bonding or eutectic bonding technology, which enables the bare chip to meet the requirements of good RF grounding. An appropriate length of RF microstrip line 2 is selected according to the size of the bare chip, so that the distance between the RF microstrip line 2 and the bare chip can be as close as possible, thereby shortening the length of the bonding wire and improving RF performance. The input bonding point of the bare chip is connected to one end of the left RF microstrip line 2 through the bonding wire, and the output bonding point of the bare chip is connected to one end of the right RF microstrip line 2 through the bonding wire. The other end of the left RF microstrip line 2 is connected to one end of the left RF connector 3, which serves as the input end of the test equipment. The other end of the right RF microstrip line 2 is connected to one end of the right RF connector 3, which serves as the output end of the test equipment. During testing, the test signal is a microwave signal, which is converted into an RF microstrip line 2 through the left RF connector 3 for transmission. After passing through the RF chip, it is converted back into a microwave signal through the right RF connector 3 and output to the test equipment.
[0036] Furthermore, to ensure that the height of the bare chip after assembly into the first mounting region 111 is consistent with the height of the RF microstrip line 2 after assembly into the second mounting region 112, a second groove 12 is provided in the first mounting region 111. The high end of the bare chip and the high end of the RF microstrip line 2 are located on the same horizontal plane within the second groove 12. This arrangement satisfies the requirements for short bonding wire length and high RF frequency. In other embodiments, for cases where the RF frequency is not high and the bonding wire length is not required, the second groove 12 can be omitted, and the bare chip can be directly assembled into the first mounting region 111 within the first groove 11.
[0037] In this embodiment, the distance between the end of the RF microstrip line 2 closest to the bare chip and the bare chip is greater than or equal to 25 micrometers. Since the RF microstrip line 2 can be selected according to the size of the bare chip, the distance between the RF microstrip line 2 and the bare chip is not limited by traditional PCB manufacturing processes. This reduces the length of the bonding wire required to connect the RF microstrip line 2 to the bare chip, lowers the possibility of poor high-frequency RF performance due to excessively long bonding wires, provides a good testing foundation and environment, and thus improves RF testing performance.
[0038] The test fixture also includes a grounding post 6 for leading out a ground wire. An RF insulator 21 is provided at the end of the RF microstrip line 2 furthest from the bare chip, ensuring that the signal transmission path is insulated from the base 1. The RF insulator 21 includes a first connecting part, a second connecting part, and a grounding part. The first connecting part connects to the RF microstrip line 2, the second connecting part connects to the RF connector 3, and the grounding part connects to the grounding post 6. The grounding post 6 is located on the base 1 for easy testing. Specifically, the grounding post 6 has external threads, and the base 1 has a through hole for mounting the grounding post 6 with internal threads. The grounding post 6 and the base 1 are connected and fixed by a threaded connection.
[0039] Furthermore, a gold-plated layer 13 (not shown in the figure) is provided at the bottom of the first groove 11 and the bottom of the second groove 12, and the bare chip is fixedly disposed on the gold-plated layer 13. On the one hand, in some embodiments, the bare chip is assembled to the bottom of the first groove 11 or the bottom of the second groove 12 using a eutectic bonding process. Since gold has excellent conductivity and is resistant to oxidation, it can significantly reduce contact resistance and ensure good electrical contact of the bare chip. The low resistance and low contact impedance of the gold plating can reduce signal reflection and loss, especially at high frequencies, where the skin effect is obvious. The high conductivity of gold helps to reduce the influence of skin depth, maintain the stability of signal transmission, and improve RF performance. On the other hand, the combination of the gold-plated layer 13 and the aluminum substrate, when the bare chip contacts the fixture, forms a continuous conductive path through the low impedance connection between the metals (such as welding or crimping), ensuring that the high-frequency current is quickly discharged to the ground, reducing the inductance of the grounding loop, thereby improving the grounding effect.
[0040] The cover plate 4 is located on the upper surface of the base 1 and is used to cover the first groove 11, protecting the bare chip and preventing accidental contact with the bonding wires, thus ensuring normal testing of the bare chip. In this embodiment, the base 1 is provided with a second mounting hole 15. Bolts pass through the cover plate 4 and the second mounting hole 15 to fix the cover plate 4 to the base 1. The cover plate 4 is preferably an acrylic cover plate 4. Acrylic cover plates 4 are simple to process, are flat and are not affected by folding, and can be made into any rectangular size. Compared with the shape of traditional protective cover folding lids, acrylic cover plates 4 are simple to process and reduce processing costs.
[0041] Based on the aforementioned universal test fixture version for two RF channels of the bare chip, multiple universal test fixtures for different RF channels can be made according to the number of RF channels on the bare chip, and notches can be added as needed to connect power lines. For details, please refer to [link to relevant documentation]. Figure 3 , Figure 3 In another embodiment of the test fixture disclosed in this application, the bare chip has four radio frequency (RF) channels. These four RF channels are arranged asymmetrically. Four RF microstrip lines 2 and four RF connectors 3 are each provided. The four RF microstrip lines 2 are respectively located on the periphery of the bare chip, corresponding one-to-one with the four RF channels. The four RF connectors 3 are respectively located on the periphery of the base 1, with the RF microstrip lines 2 and RF connectors 3 corresponding one-to-one. Please refer to [link / reference]. Figure 4 In some other embodiments, the bare chip has four radio frequency (RF) channels, which are arranged in a centrally symmetrical structure. Four RF microstrip lines 2 are arranged centrally symmetrically around the first mounting area 111, and four RF connectors 3 are arranged centrally symmetrically around the base 1. Depending on the RF channels of the bare chip, the number of RF microstrip lines 2 and RF connectors 3 can be increased to accommodate different bare chips, reducing design and production cycles, lowering high processing costs, and improving the versatility of the test fixture.
[0042] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A test fixture, characterized in that, include: The base is provided with a first groove, the first groove being provided with a first mounting area for mounting a bare chip and a second mounting area, the second mounting area surrounding the first mounting area. A radio frequency microstrip line is disposed in the second mounting area, and the radio frequency microstrip line is connected to the bare chip by a bonding wire. An RF connector is provided, corresponding to the RF microstrip line and passing through the base, wherein the RF microstrip line is connected to the RF connector.
2. The test fixture according to claim 1, characterized in that, The first installation area is provided with a second groove.
3. A test fixture according to claim 2, characterized in that, The bottom of the first groove and the bottom of the second groove are provided with a gold plating layer, and the bare chip is fixedly disposed on the gold plating layer.
4. A test fixture according to claim 3, characterized in that, It also includes a grounding post for leading out a ground wire, the grounding post being disposed on the base.
5. A test fixture according to claim 4, characterized in that, An RF insulator is provided at the end of the RF microstrip line away from the bare chip. The RF insulator includes a first connection part, a second connection part, and a grounding part. The first connection part is connected to the RF microstrip line, the second connection part is connected to the RF connector, and the grounding part is connected to the grounding post.
6. A test fixture according to claim 1, characterized in that, The distance between the end of the radio frequency microstrip line closest to the bare chip and the bare chip is greater than or equal to 25 micrometers.
7. A test fixture according to claim 1, characterized in that, Multiple radio frequency microstrip lines and radio frequency connectors are provided. Multiple radio frequency microstrip lines are located in the second mounting area and are spaced apart. Multiple radio frequency connectors are provided on the base in a one-to-one correspondence with multiple radio frequency microstrip lines.
8. A test fixture according to claim 7, characterized in that, The plurality of radio frequency microstrip lines are arranged in a centrally symmetrical manner around the first mounting area, and the plurality of radio frequency connectors are arranged in a centrally symmetrical manner around the base.
9. A test fixture according to claim 1, characterized in that, The base is an aluminum base, and the base is provided with multiple first mounting holes. Bolts pass through the first mounting holes for connection with the external copper base to enhance heat dissipation.
10. A test fixture according to claim 1, characterized in that, It also includes a cover plate for covering the first groove; the base is provided with a second mounting hole, and bolts pass through the cover plate and the second mounting hole to fix the cover plate to the base.