A multi-area replaceable combination probe card for machine status inspection

Abstract

The present invention relates to the field of semiconductor testing technology, and discloses a multi-area replaceable combination probe card for machine status inspection, comprising: a disk, a wafer surface provided on the disk surface, a modular MLC structure provided on the wafer surface, the modular MLC structure comprising a plurality of independent small MLCs evenly distributed within the disk area with a wafer surface size of 300 mm, the plurality of small MLCs being fixedly connected to a conductive path and integrated into a PCB, and a plurality of probes. By replacing the traditional monolithic ceramic MLC with a plurality of independent small MLCs, the probe card can flexibly adapt to different sizes and quantities of DUTs, meeting diverse testing requirements. Furthermore, the small MLCs are simple to manufacture, reducing material loss and manufacturing costs, significantly reducing raw material waste, and enabling independent replacement of damaged individual MLCs to avoid scrapping the entire card, thus addressing the limitations of traditional designs in flexibility and cost control.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor testing technology, in particular to a multi-area replaceable combination probe card for machine status inspection. Background Art

[0002] In the semiconductor industry, accurate inspection of machine status is crucial to ensuring high quality and high efficiency in chip production. Probe cards serve as the key interface between ATE testers and semiconductor wafers, and their performance directly affects the accuracy and efficiency of testing. With the continuous advancement of chip technology, the requirements for probe cards are also increasing, requiring them to have greater flexibility, interchangeability, and adaptability.

[0003] Traditional MEMS probe cards typically use a single piece of ceramic as the MLC structure. This design has limitations in flexibility and cost control. The manufacturing cost of the single piece of ceramic is high and it is difficult to adapt to different sizes and numbers of DUTs. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a multi-area replaceable combination probe card for machine status inspection, which solves the problems of limitations in flexibility and cost control.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a multi-area replaceable combination probe card for machine status inspection, comprising:

[0006] A disk, wherein a wafer surface is provided on the disk surface, and a modular MLC structure is provided on the wafer surface. The modular MLC structure consists of multiple independent small MLC blocks evenly distributed within the disk range of the 300mm wafer surface size, and the multiple small MLC blocks are integrated into the PCB by being fixedly connected with the conductive path;

[0007] Multiple probes, each of which is located on the surface of a small MLC, with a reflective surface provided at the probe tip for optical flatness measurement. The reflective surface also enables electrical testing by physically contacting the aluminum wafer. The probes are connected to a POGO point on the tester interface of the PCB via a conductive path.

[0008] Temperature probes are located at the edge of the probe card, with a measurement accuracy of ±0.1°C, and are used to monitor the test environment temperature in real time.

[0009] A signal transmission module, wherein the signal transmission module is used for signal transmission, and the signal transmission impedance is ≤0.1Ω.

[0010] Preferably, the material of the small MLC blocks is aluminum nitride ceramics, the size of a single block is 10 mm×10 mm×0.5 mm, the adjacent spacing is 5 mm, and they are distributed in a ring array.

[0011] Preferably, the probe is made of beryllium copper alloy, the tip diameter is 50 μm, the thickness of the gold-plated layer on the surface is 0.5 μm, and the reflectivity of the reflective surface is ≥90%.

[0012] Preferably, the temperature probe is a miniature thermocouple or an infrared sensor, which communicates with the PCB via an SPI interface.

[0013] Preferably, the probe is used to contact the aluminum wafer to implement electrical testing, and the pressure applied when contacting the aluminum wafer is controlled to 20-30 gf by a spring structure.

[0014] Preferably, a reflective surface is provided at the probe tip. The reflective surface material has high reflectivity and a surface roughness of less than 0.1 μm. It is used for optical focusing of the probe camera to achieve optical flatness measurement. The optical measurement accuracy can reach ±0.01 mm.

[0015] Preferably, the probe is connected to the PCB through metal welding, and a signal shielding layer is provided on the PCB.

[0016] Preferably, the small MLC pieces are connected by mechanical snap connections with a snap accuracy of ±0.05mm, and are fixed by a combination of screw fastening and glue-assisted fixation, with the screws being made of high-strength stainless steel.

[0017] Preferably, the conductive path is made of low-resistance graphene material to ensure stable signal transmission.

[0018] Preferably, the probes are distributed in an equilateral triangle on each small MLC, the probe spacing is 2 mm, and the probes on adjacent MLCs are staggered.

[0019] Working Principle: The probe card uses a disc as its base platform. The wafer surface simulates the actual wafer test environment. The modular MLC structure consists of multiple small MLCs evenly distributed within the disc area of ​​​​the 300mm wafer surface size and fixedly connected to the PCB through conductive paths.

[0020] The small MLCs are made of aluminum nitride ceramic, which uses its excellent thermal conductivity to dissipate test heat, preventing local overheating from affecting accuracy. The electrical insulation prevents signal interference between small blocks. The single block size is 10mm×10mm×0.5mm, with adjacent blocks spaced 5mm apart and distributed in a ring array. This not only effectively covers the wafer surface, but also disperses the test pressure and optimizes the spatial layout.

[0021] Multiple probes are placed on the surface of small MLCs. They are made of beryllium copper alloy and plated with gold to ensure conductivity and corrosion resistance. The reflectivity of the reflective surface of the probe tip is ≥90% and the surface roughness is less than 0.1μm. The light emitted by the prober camera is reflected by the reflective surface, and the reflected light is analyzed to achieve optical flatness measurement with an accuracy of ±0.01mm. At the same time, the probe contacts the aluminum wafer with a pressure of 20-30gf for electrical testing, transmitting the test signal and collecting the feedback signal. The probes on each small MLC are distributed in an equilateral triangle with a spacing of 2mm. The probes on adjacent MLCs are staggered to reduce signal interference.

[0022] The temperature probe is located at the edge of the probe card and can be a miniature thermocouple or an infrared sensor. The former is based on the thermoelectric effect, while the latter measures temperature by detecting infrared radiation with a measurement accuracy of ±0.1°C. The temperature data is transmitted to the PCB via the SPI interface for temperature compensation of test data or test parameter adjustment.

[0023] The conductive path uses low-resistance graphene material, and combined with the signal transmission module, the signal transmission impedance is ≤0.1Ω, ensuring low-loss and distortion-free transmission of various signals.

[0024] The probe is connected to the PCB through metal welding to ensure stable electrical connection. The signal shielding layer on the PCB blocks external electromagnetic interference. The small MLCs are connected with mechanical clips with an accuracy of ±0.05mm, and fastened with high-strength stainless steel screws and glue to ensure a stable structure. This allows the probe card to operate stably for a long time and realize accurate inspection of the machine status.

[0025] The present invention provides a multi-area replaceable combination probe card for machine status inspection. It has the following beneficial effects:

[0026] 1. The present invention replaces the traditional whole ceramic MLC with multiple independent small MLCs, which enables the probe card to flexibly adapt to DUTs of different sizes and quantities to meet diverse testing requirements. At the same time, the small MLCs are simple to manufacture, reduce material loss, and reduce manufacturing costs, thus significantly reducing the waste of raw materials. When a single MLC is damaged, it can be replaced independently to avoid the scrapping of the entire card, thus solving the limitations of traditional designs in flexibility and cost control.

[0027] 2. The present invention integrates an optical reflective surface with a reflectivity of ≥90% through the probe, and has an electrical contact function with a contact pressure of 20-30gf. Optical focusing and electrical testing are completed simultaneously. The probe surface is plated with a 0.5μm gold layer and a low-resistance graphene conductive path with a resistivity of ≤1×10⁻ 6 Ω·m ensures the stability of electrical signal transmission, and the contact resistance is ≤0.1Ω, which enables the multifunctional probe to realize the integration of test processes.

[0028] 3. The temperature probe of this invention monitors the ambient temperature in real time with a high precision of ±0.1°C, and compensates or adjusts the test to avoid temperature influence. The signal transmission module impedance is ≤0.1Ω, ensuring stable signal transmission. The integrated design of each component optimizes the spatial layout and stabilizes the mechanical and electrical connections, comprehensively guaranteeing the accuracy and stability of the machine status inspection. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a three-dimensional diagram of the arrangement of small MLC blocks in a multi-area replaceable combination probe card for machine status inspection of the present invention;

[0030] Figure 2 This is a top view of the arrangement of small MLC blocks in a multi-area replaceable combination probe card for machine status inspection according to the present invention;

[0031] Figure 3 This is a schematic plan view of the arrangement of small MLC blocks in a multi-region replaceable combination probe card for machine status inspection according to the present invention;

[0032] Figure 4 A schematic diagram of a disk of a multi-area replaceable combination probe card for machine status inspection according to the present invention;

[0033] Figure 5 The figure is a schematic diagram of probes of a multi-area replaceable combination probe card for machine status inspection according to the present invention.

[0034] Among them, 1. small piece of MLC; 2. PCB; 3. probe; 31. reflective surface; 4. temperature probe; 5. disk; 6. wafer surface. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0036] Please see the attached Figure 1 -Attached Figure 5 An embodiment of the present invention provides a multi-area replaceable combination probe card for machine status inspection, comprising:

[0037] A disk 5 is provided with a wafer surface 6 on the surface of the disk 5. A modular MLC structure is provided on the surface of the wafer surface 6. The modular MLC structure consists of multiple independent small MLC blocks 1 evenly distributed within the disk 5 with a size of 300mm wafer surface 6. The multiple small MLC blocks 1 are integrated into the PCB 2 by fixed connection with the conductive path;

[0038] The disc 5 serves as the basic support structure of the entire probe card, providing a stable installation plane for each component. The wafer surface 6 simulates the actual wafer test scenario to ensure the consistency of the test environment. The modular MLC structure design enables the probe card to flexibly adjust the number and layout of small MLC blocks 1 according to different test requirements. The number of small MLC blocks 1 can be selected according to demand, 9, 17, 21 or more. Multiple small MLC blocks 1 are evenly distributed within the range of the disc 5 with the size of 300mm wafer surface 6, which can cover a larger test area and improve test efficiency. They are fixedly connected and integrated into PCB 2 through conductive paths, realizing effective transmission and processing of electrical signals.

[0039] Multiple probes 3 are located on the surface of the small MLC 1. The tips of the probes 3 are provided with a reflective surface 31, which is used for optical flatness measurement. At the same time, electrical testing is achieved by physically contacting the aluminum wafer. The probes 3 are connected to the tester interface POGO point of the PCB through a conductive path.

[0040] Multiple probes 3 are key components for achieving multiple test functions. They are located on the surface of the small MLC1 and are convenient for close contact with the object under test. The reflective surface 31 of the probe 3 tip works based on the principle of optical reflection. When the probe camera emits light to the reflective surface 31, the reflected light carries information about the relative position of the probe tip and the wafer surface. By analyzing the reflected light, the optical flatness of the wafer can be accurately measured. At the same time, the probe 3 physically contacts the aluminum wafer to transmit and collect electrical signals, completing electrical testing. It is connected to the test machine interface POGO point of the PCB through a conductive path to ensure that the test signal can be transmitted to the test equipment for analysis and processing.

[0041] Temperature probe 4, which is located at the edge of the probe card and has a measurement accuracy of ±0.1°C, is used to monitor the test environment temperature in real time;

[0042] The temperature probe 4 is located at the edge of the probe card. This ensures that it does not affect the normal operation of other components while effectively sensing temperature changes in the test environment. Its measurement accuracy reaches ±0.1°C, enabling it to capture even small fluctuations in ambient temperature. Since temperature significantly affects the electrical and optical properties of semiconductor materials, real-time monitoring of the test environment temperature allows for timely detection of temperature anomalies. This allows for temperature compensation of test data or adjustment of test parameters, ensuring that the machine status inspection results are not affected by temperature fluctuations.

[0043] Signal transmission module, the signal transmission module is used for signal transmission, and the signal transmission impedance is ≤0.1Ω.

[0044] The material of the small MLC1 block is aluminum nitride ceramic, the size of a single block is 10mm×10mm×0.5mm, the adjacent spacing is 5mm, and it is distributed in a ring array.

[0045] Aluminum nitride ceramic is chosen as the material for the small piece of MLC1 because of its excellent thermal conductivity and electrical insulation. Good thermal conductivity can effectively dissipate the heat generated during the test to avoid local overheating affecting the test accuracy. Electrical insulation prevents mutual interference of electrical signals between small pieces. The single piece size of 10mm×10mm×0.5mm is set to take into account both space utilization and structural stability. The adjacent spacing is 5mm, which not only ensures sufficient electrical isolation, but also leaves reasonable space for signal transmission lines and mechanical connections. It is distributed in a ring array, which helps to evenly cover the wafer surface 6 and facilitates wiring and installation of other components, thereby improving the compactness and rationality of the overall structure.

[0046] The material of the probe 3 is beryllium copper alloy, the needle tip diameter is 50 μm, the thickness of the gold-plated layer on the surface is 0.5 μm, and the reflectivity of the reflective surface 31 is ≥90%.

[0047] Beryllium copper alloy is selected as the material of probe 3 because of its high strength, high elasticity and good conductivity. The high strength and high elasticity ensure that the probe is not easily deformed during multiple contacts with the object to be measured and can maintain stable contact pressure. The good conductivity reduces the resistance loss during signal transmission and ensures the accuracy of the electrical test signal. The needle tip diameter is 50μm, which can achieve precise physical contact without damaging the surface of the object to be measured. The surface gold plating layer is 0.5μm thick, which further enhances the conductivity and corrosion resistance and extends the service life of the probe. The reflectivity of the reflective surface 31 is ≥90%, which ensures the intensity of the optical reflection signal and improves the accuracy and reliability of the optical flatness measurement.

[0048] The temperature probe 4 is a miniature thermocouple or infrared sensor, and communicates with the PCB via an SPI interface.

[0049] Micro thermocouples and infrared sensors are both commonly used high-precision temperature measurement components. Micro thermocouples work based on the thermoelectric effect, can quickly respond to temperature changes, and directly convert temperature into electrical signal output. Infrared sensors measure temperature by detecting infrared radiation emitted by objects. They have the advantages of non-contact measurement and fast response speed. They communicate with the PCB through the SPI interface. The SPI interface has high-speed, synchronous, and full-duplex communication characteristics, ensuring that the temperature data collected by the temperature probe 4 is transmitted to the PCB for subsequent real-time processing and analysis of the temperature data.

[0050] The probe 3 is used to contact the aluminum wafer to implement electrical testing. The pressure applied when contacting the aluminum wafer is controlled by a spring structure to be 20-30 gf.

[0051] When probe 3 contacts the aluminum wafer for electrical testing, the applied pressure needs to be controlled at 20-30gf. If the pressure is too small, poor contact between the probe and the aluminum wafer will result, resulting in contact resistance, which will affect the accuracy of the electrical test results. If the pressure is too large, the surface of the aluminum wafer will be scratched or damaged. The pressure is controlled by the spring structure to ensure good electrical contact while avoiding damage to the object under test, thereby ensuring the stability and reliability of the electrical test process.

[0052] The probe 3 has a reflective surface 31 at its tip. The reflective surface 31 is made of a material with high reflectivity and a surface roughness of less than 0.1 μm. It is used for optical focusing of the probe camera to achieve optical flatness measurement. The optical measurement accuracy can reach ±0.01 mm.

[0053] The reflective surface 31 at the tip of probe 3 is made of a material with high reflectivity, ensuring sufficient reflected light intensity for easy capture by the probe camera. The surface roughness is less than 0.1μm, making the reflected light more regular and reducing errors caused by diffuse reflection. The probe camera uses the light reflected by the reflective surface 31 for optical focusing. Based on the principle of optical imaging, it measures the relative position of the probe tip and the wafer surface, thereby achieving optical flatness measurement. The optical measurement accuracy can reach ±0.01mm, which helps to promptly detect potential flatness problems on the machine.

[0054] The probe 3 is connected to the PCB 2 through metal welding, and a signal shielding layer is provided on the PCB 2.

[0055] The probe 3 and PCB2 are connected by metal welding, which can form a strong physical connection and good electrical conductivity. This connection method has high stability and can withstand the vibration and stress during multiple tests, ensuring that the electrical connection between the probe 3 and PCB2 is strong. The signal shielding layer set on PCB2 can effectively block the influence of external electromagnetic interference on the test signal. In a complex electromagnetic environment, the signal shielding layer can prevent the external electromagnetic field from coupling into the test signal line, ensuring the purity of the test signal during transmission.

[0056] Small pieces of MLC1 are connected by mechanical snap-fit ​​connections with an accuracy of ±0.05mm. They are fixed by a combination of screw fastening and glue-assisted fixation. The screws are made of high-strength stainless steel.

[0057] Small MLC1 blocks are connected by mechanical snap connections with an accuracy of ±0.05mm. The high-precision snap connections ensure the accuracy of the relative positions between the small MLC1 blocks, which is beneficial to the stability and consistency of the overall structure. Screw fastening provides the main connection force. The high-strength stainless steel screws have good corrosion resistance and high strength, and can remain fastened during long-term use. Glue-assisted fixation further enhances the tightness of the connection, fills the tiny gap between the mechanical snap connections and the screw connections, and prevents relative displacement between the small MLC1 blocks due to vibration or external force, thereby ensuring the stability of the entire modular MLC structure and the long-term stable operation of the probe card.

[0058] The conductive path uses low-resistance graphene material to ensure stable signal transmission.

[0059] The conductive path is made of low-resistance graphene material. Graphene has excellent electrical properties and a two-dimensional crystal structure, which gives it extremely high electron mobility and ultra-low resistance characteristics. This ensures that when the test signal is transmitted in the conductive path, the energy loss is extremely small and the signal attenuation is negligible, effectively avoiding signal distortion, thereby ensuring that the electrical and optical test signals collected from probe 3 and the temperature signal transmitted by temperature probe 4 can be stably and accurately transmitted to the PCB for processing and analysis.

[0060] The probes 3 are distributed in an equilateral triangle on each small MLC1, with a probe spacing of 2 mm, and the probes 3 on adjacent MLCs are staggered.

[0061] The probes 3 are distributed in an equilateral triangle on each small piece of MLC1. This distribution method has high space utilization and can reasonably arrange multiple probes on the limited surface of the small piece of MLC1. The geometric structure of the equilateral triangle enables the probes to support each other, enhances the measurement stability, and helps to reduce electromagnetic interference between the probes. The probe spacing is 2mm, which ensures sufficient electrical isolation between the probes without affecting the comprehensiveness of the measurement due to the large spacing. The probes 3 on adjacent MLCs are staggered, which further reduces the signal interference between probes on different small pieces of MLC1, so that each probe can independently obtain measurement data.

[0062] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A multi-area replaceable combination probe card for machine status inspection, characterized in that: include: A disk (5), wherein a wafer surface (6) is provided on the surface of the disk (5), and a modular MLC structure is provided on the surface of the wafer surface (6), wherein the modular MLC structure comprises a plurality of independent small MLCs (1) uniformly distributed within the range of the disk (5) having a size of 300 mm of the wafer surface (6), and the plurality of small MLCs (1) are integrated into a PCB (2) by being fixedly connected to a conductive path; A plurality of probes (3), each of the plurality of probes (3) is located on the surface of the small MLC (1), a reflective surface (31) is provided at the tip of the probe (3), the reflective surface (31) is used for optical flatness measurement, and electrical testing is simultaneously achieved by physically contacting the aluminum wafer, the probe (3) is connected to a test machine interface POGO point of the PCB via a conductive path; A temperature probe (4), which is distributed at the edge of the probe card and has a measurement accuracy of ±0.1°C and is used to monitor the test environment temperature in real time; A signal transmission module, wherein the signal transmission module is used for signal transmission, and the signal transmission impedance is ≤0.1Ω.

2. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The material of the small MLC (1) is aluminum nitride ceramic, the size of a single piece is 10 mm×10 mm×0.5 mm, the adjacent spacing is 5 mm, and they are distributed in a ring array.

3. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The material of the probe (3) is beryllium copper alloy, the needle tip diameter is 50 μm, the thickness of the gold-plated layer on the surface is 0.5 μm, and the reflectivity of the reflective surface (31) is ≥90%.

4. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The temperature probe (4) is a miniature thermocouple or an infrared sensor, and communicates with the PCB via an SPI interface.

5. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The probe (3) is used to contact the aluminum wafer to implement electrical testing, and the pressure applied when contacting the aluminum wafer is controlled to 20-30 gf by a spring structure.

6. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The probe (3) is provided with a reflective surface (31) at the tip thereof. The reflective surface (31) is made of a material with high reflectivity and a surface roughness of less than 0.1 μm. The reflective surface (31) is used for optical focusing of a probe camera to achieve optical flatness measurement. The optical measurement accuracy can reach ±0.01 mm.

7. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The probe (3) is connected to the PCB (2) through metal welding, and a signal shielding layer is provided on the PCB (2).

8. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The small MLC pieces (1) are connected by mechanical snap fastening with a snap fastening accuracy of ±0.05 mm, and are fixed by a combination of screw fastening and glue auxiliary fixation, and the screws are made of high-strength stainless steel.

9. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The conductive path adopts low-resistance graphene material to ensure stable signal transmission.

10. The multi-area replaceable combination probe card for machine status inspection according to claim 1, characterized in that: The probes (3) are distributed in an equilateral triangle on each small MLC (1), with a probe spacing of 2 mm, and the probes (3) on adjacent MLCs are arranged in staggered positions.

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