High-efficiency electrical property testing method based on gold bump manufacturing process

Abstract

The invention provides an efficient electrical property testing method based on a gold bump manufacturing process. The efficient electrical property testing method based on the gold bump manufacturing process comprises the steps of a, preparing a gold bump: preparing the gold bump on a device to be tested by adopting an electron beam evaporation process, and precisely optimizing the shape and the size of the gold bump, and b, designing a testing contact: arranging a corresponding testing contact on a testing platform, designing the testing contact with a self-adjusting microstructure, the self-adjusting microstructure comprises a flexible contact layer with an elastic deformation characteristic and is used for absorbing stress concentration generated by micron-order alignment deviation. According to the high-efficiency electrical property testing method based on the gold bump manufacturing process, real-time position monitoring is carried out by adopting high-precision optical equipment and a laser interferometer technology, and automatic alignment adjustment is carried out in combination with a micro servo driver, so that the contact precision between the gold bump and a testing contact can reach the nanoscale; the reliability and precision of the test are remarkably improved, and poor contact or local damage is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical testing, and in particular to a high-efficiency electrical testing method based on a gold bump process. Background Art

[0002] The efficient electrical testing method based on the gold bump process mainly forms gold bumps on the key electrical contacts of the device under test as a conductive medium between the test probe and the device, thereby achieving low-impedance, high-reliability contact connection. The basic structure of this method generally includes: first, preparing uniform and stable gold bumps on the surface of the device through precision metal deposition or electroplating processes; second, using high-precision alignment mechanisms and mechanical clamping devices to accurately connect the gold bumps with the preset metal contacts on the test platform; finally, relying on high-performance electrical measuring instruments to quickly test multiple indicators such as DC, AC parameters and signal integrity of the device. Its basic principle is to utilize the excellent conductivity and chemical stability of gold to achieve fast and low-loss electrical connections through gold bumps, while coordinating with automated alignment and stable contact pressure to ensure the accuracy and repeatability of test data.

[0003] While this testing method offers significant advantages in terms of increased inspection speed and data accuracy, the system itself has some drawbacks. Currently, strict micron-level alignment requirements are required between the gold bumps and the test contacts; even the slightest deviation can lead to poor contact or localized damage, compromising test reliability. Frequent mechanical contact can also cause wear and fatigue. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a high-efficiency electrical testing method based on the gold bump process, which solves the problem that the micron-level alignment requirements between the gold bumps and the test contacts are high, and a slight deviation may lead to poor contact or local damage, thereby affecting the test reliability; and solves the problem that frequent mechanical contact may also cause wear and fatigue problems.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a high-efficiency electrical testing method based on a gold bump process, comprising:

[0006] a. Gold bump preparation: The gold bump is prepared on the device under test using electron beam evaporation technology. Its shape and size are precisely optimized and designed according to the model formula.

[0007] F contact =k·δ

[0008] Determine the contact stiffness k and displacement difference δ of the gold bump to ensure the expected contact pressure;

[0009] b. Test contact design: Corresponding test contacts are set on the test platform. The test contacts are designed with self-adjusting microstructures. The self-adjusting microstructures include a flexible contact layer with elastic deformation characteristics, which is used to absorb stress concentration caused by micron-level alignment deviations;

[0010] c. Real-time position monitoring device: Use high-precision optical equipment to monitor the relative position of the gold bump and the test contact in real time to obtain position information data;

[0011] d. Automatic alignment adjustment: Based on the position information fed back in step c, the gold bump or test platform is fine-tuned by the micro servo driver to correct the displacement error in real time. The adjustment amount is based on the model formula

[0012] Δ=k1·X error +k2·Y error

[0013] Calculation, where k1 and k2 are preset correction coefficients, X error and Y error are the horizontal and vertical deviation values ​​respectively;

[0014] e. Precise contact pressure: Apply appropriate contact pressure to the adjusted gold bumps and test contacts to form a low-impedance, stable electrical connection between the two under optimal conditions;

[0015] f. Contact status detection: A contact impedance measurement device is used to detect the contact status in real time. The detection principle is based on Ohm's law R = V / I to ensure that the contact impedance is within the set range;

[0016] g. Test signal transmission equipment: transmits and collects test signals through low-loss, high-precision electrical measuring instruments to obtain various electrical parameters of the device;

[0017] h. Closed-loop feedback control algorithm: Adopts an adaptive closed-loop feedback control algorithm to monitor the test process and correct contact errors caused by environmental changes or device deformation in real time;

[0018] i. Digital signal processing module: performs digital signal processing on the collected test data, and uses filtering and statistical correction methods to eliminate noise introduced by micro-displacement deviation;

[0019] j. Low wear coating application: low friction, high wear resistant material is coated on the test contact surface of the gold bump. The coating thickness and material parameters are calculated by the formula

[0020] T opt =f(Material,Pressure)

[0021] Optimized design to reduce wear and fatigue caused by frequent mechanical contact.

[0022] Preferably, the gold bump is hemispherical in shape, and the flexible contact layer is made of a material with self-recovery properties to improve the durability and long-term stability of the contact layer.

[0023] Preferably, the real-time position monitoring device uses laser interferometer technology to achieve nanometer-level precision displacement measurement and ensure high-precision feedback of micron-level alignment.

[0024] Preferably, the test signal transmission device includes a low noise amplifier, a digital signal processor and a high-bandwidth transmission line.

[0025] Preferably, the closed-loop feedback control algorithm is based on fuzzy control and adjusts the operating parameters of the test system in real time to ensure that contact errors caused by environmental changes or device deformation are effectively corrected.

[0026] Preferably, the low-friction, high-wear-resistant coating is made of a diamond film and is prepared by a chemical vapor deposition process, and the coating thickness is 10-50 μm.

[0027] Preferably, the surface of the gold bump is nano-polished to further reduce contact resistance and increase contact stability.

[0028] Preferably, the digital signal processing module adopts low-pass filtering, Kalman filtering or wavelet transform method to improve the quality of test data and reduce noise interference.

[0029] The present invention provides a high-efficiency electrical testing method based on a gold bump process. It has the following beneficial effects:

[0030] This high-efficiency electrical testing method based on the gold bump process uses high-precision optical equipment and laser interferometer technology for real-time position monitoring, and combines it with a micro-servo drive for automatic alignment adjustment. The present invention can ensure that the contact accuracy between the gold bump and the test contact reaches the nanometer level, significantly improving the reliability and accuracy of the test and avoiding the occurrence of poor contact or local damage. Secondly, to address the wear and fatigue problems caused by frequent mechanical contact, the present invention coats the surface of the gold bump test contact with a low-friction, high-wear-resistant material, such as a diamond film, and prepares it through a chemical vapor deposition process. This design greatly improves the durability and long-term stability of the test contact, reduces wear on the equipment during long-term use, and extends the service life of the system.

[0031] The present invention also focuses on overall optimization in system design to ensure the efficiency and stability of the test process. By introducing a closed-loop feedback control algorithm, the system can monitor and correct contact errors caused by environmental changes or device deformation in real time to ensure the accuracy of the test results. The digital signal processing module effectively eliminates the noise introduced by micro-displacement deviations through low-pass filtering, Kalman filtering or wavelet transform methods, further improving the quality of the test data. In addition, the system uses low-noise amplifiers, digital signal processors and high-bandwidth transmission lines in the design of signal transmission equipment to ensure high-precision transmission of test signals and data acquisition. These advantages not only enable the electrical testing method of the present invention to adapt to various complex test environments, but also greatly improve the automation level and test efficiency of the system, providing strong technical support for high-precision, large-scale electrical testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the 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.

[0034] like Figure 1 As shown, the embodiment of the present invention provides an efficient electrical testing method based on a gold bump process, including: a. Gold bump preparation: gold bumps are prepared on the device to be tested using an electron beam evaporation process, and their shape and size are precisely optimized and designed according to the model formula

[0035] F contact =k·δ

[0036] The contact stiffness k and displacement difference δ of the gold bump are determined to ensure the expected contact pressure. The shape of the gold bump is hemispherical, and the flexible contact layer uses a material with self-recovery properties to improve the durability and long-term stability of the contact layer.

[0037] b. Test contact design: Corresponding test contacts are set on the test platform. The test contacts are designed with self-adjusting microstructures. The self-adjusting microstructures include flexible contact layers with elastic deformation characteristics, which are used to absorb stress concentration caused by micron-level alignment deviations.

[0038] c. Real-time position monitoring device: Utilize high-precision optical equipment to monitor the relative position of the gold bump and the test contact in real time and obtain position information data. The real-time position monitoring device uses laser interferometer technology to achieve nanometer-level precision displacement measurement and ensure high-precision feedback of micron-level alignment. During the test process, changes in ambient temperature, humidity, and vibration factors may cause contact errors between the gold bump and the test contact. In order to solve this problem, the present invention adds a dynamic environmental compensation module, which dynamically adjusts the contact pressure and alignment accuracy of the gold bump and the test contact by monitoring environmental changes in real time and transmitting feedback data to a closed-loop feedback control system. The environmental compensation module can effectively reduce the impact of external factors on the test results, thereby improving the reliability and accuracy of the test.

[0039] Ambient temperature monitoring and compensation

[0040] Temperature range: Ambient temperature changes can fluctuate between -10°C and +50°C.

[0041] Temperature sensor accuracy: The ambient temperature sensor has a measurement accuracy of ±0.1°C and can accurately monitor temperature changes.

[0042] Temperature alignment compensation: Each temperature change of 1°C will cause the contact error between the gold bump and the test contact to change by about 0.2μm. Therefore, the compensation system can adjust the displacement of the micro servo drive based on real-time temperature data to keep the contact error within ±1μm.

[0043] Humidity monitoring and compensation

[0044] Humidity range: The ambient humidity range is 10% to 90% RH (relative humidity).

[0045] Humidity sensor accuracy: The humidity sensor has an accuracy of ±2% RH, ensuring prompt response to humidity changes.

[0046] Humidity impact on contact accuracy: Humidity changes can cause material expansion or contraction, affecting the contact between the gold bump and the test contact. The compensation system adjusts the contact pressure to compensate for errors of approximately ±0.1μm when humidity changes.

[0047] Vibration compensation

[0048] Vibration frequency range: The system can operate normally in an environment with a vibration frequency range of 10Hz to 50Hz.

[0049] Vibration amplitude: The dynamic environmental compensation module can compensate the contact point in a vibration environment with an amplitude of ±5μm to avoid displacement errors caused by vibration.

[0050] Impact of vibration on contact error: Vibration may cause a maximum displacement of 1μm at the contact point. The compensation module can correct this error to within ±0.2μm by adjusting the servo drive in real time.

[0051] Compensation response speed and accuracy

[0052] Feedback response time: The feedback response time of the dynamic environmental compensation module is within 50ms, ensuring that the system can quickly respond to environmental changes and adjust contact accuracy in real time.

[0053] Precision maintenance: After the compensation system is adjusted, the contact error can be controlled within the range of ±1μm, ensuring stability and high precision during the test process.

[0054] d. Automatic alignment adjustment: Based on the position information fed back in step c, the gold bump or test platform is fine-tuned by the micro servo driver to correct the displacement error in real time. The adjustment amount is based on the model formula

[0055] Δ=k1·X error +k2·Y error

[0056] Calculation, where k1 and k2 are preset correction coefficients, X error and Y error are the horizontal and vertical deviation values ​​respectively.

[0057] e. Precise contact pressure: Apply appropriate contact pressure to the adjusted gold bumps and test contacts to form a low-impedance, stable electrical connection between the two under optimal conditions.

[0058] f. Contact status detection: A contact impedance measurement device is used to detect the contact status in real time. The detection principle is based on Ohm's law R = V / I to ensure that the contact impedance is within the set range.

[0059] g. Test signal transmission equipment: transmit and collect test signals through low-loss, high-precision electrical measuring instruments to obtain various electrical parameters of the device.

[0060] h. Closed-loop feedback control algorithm: An adaptive closed-loop feedback control algorithm is used to monitor the test process and correct contact errors caused by environmental changes or device deformation in real time. The closed-loop feedback control algorithm is based on fuzzy control and adjusts the operating parameters of the test system in real time to ensure that contact errors caused by environmental changes or device deformation are effectively corrected. The digital signal processing module uses low-pass filtering, Kalman filtering, or wavelet transform methods to improve the quality of test data and reduce noise interference.

[0061] i. Digital signal processing module: This module performs digital signal processing on the collected test data, using filtering and statistical correction methods to eliminate noise introduced by micro-displacement deviations. The test signal transmission equipment includes a low-noise amplifier, a digital signal processor, and a high-bandwidth transmission line.

[0062] j. Low wear coating application: low friction, high wear resistant material is coated on the test contact surface of the gold bump. The coating thickness and material parameters are calculated by the formula

[0063] T opt =f(Material,Pressure)

[0064] The design is optimized to reduce wear and fatigue caused by frequent mechanical contact. The low-friction, high-wear-resistant coating is made of diamond film through chemical vapor deposition process. The coating thickness is 10-50μm. The surface of the gold bump is polished at the nanoscale to further reduce contact resistance and increase contact stability.

[0065] 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. An efficient electrical testing method based on a gold bump process, characterized in that: include: a. Gold bump preparation: The gold bump is prepared on the device under test using electron beam evaporation technology. Its shape and size are precisely optimized and designed according to the model formula. F contact =k·δ Determine the contact stiffness k and displacement difference δ of the gold bump to ensure the expected contact pressure; b. Test contact design: Corresponding test contacts are set on the test platform. The test contacts are designed with self-adjusting microstructures. The self-adjusting microstructures include a flexible contact layer with elastic deformation characteristics, which is used to absorb stress concentration caused by micron-level alignment deviations; c. Real-time position monitoring device: Use high-precision optical equipment to monitor the relative position of the gold bump and the test contact in real time to obtain position information data; d. Automatic alignment adjustment: Based on the position information fed back in step c, the gold bump or test platform is fine-tuned by the micro servo driver to correct the displacement error in real time. The adjustment amount is based on the model formula Δ=k1·X error +k2·Y error Calculation, where k1 and k2 are preset correction coefficients, X error and Y error are the horizontal and vertical deviation values ​​respectively; e. Precise contact pressure: Apply appropriate contact pressure to the adjusted gold bumps and test contacts to form a low-impedance, stable electrical connection between the two under optimal conditions; f. Contact status detection: A contact impedance measurement device is used to detect the contact status in real time. The detection principle is based on Ohm's law R = V / I to ensure that the contact impedance is within the set range; g. Test signal transmission equipment: transmits and collects test signals through low-loss, high-precision electrical measuring instruments to obtain various electrical parameters of the device; h. Closed-loop feedback control algorithm: Adopts an adaptive closed-loop feedback control algorithm to monitor the test process and correct contact errors caused by environmental changes or device deformation in real time; i. Digital signal processing module: performs digital signal processing on the collected test data, and uses filtering and statistical correction methods to eliminate noise introduced by micro-displacement deviation; j. Low wear coating application: low friction, high wear resistant material is coated on the test contact surface of the gold bump. The coating thickness and material parameters are calculated by the formula T opt =f(Material,Pressure) Optimized design to reduce wear and fatigue caused by frequent mechanical contact.

2. The high-efficiency electrical testing method based on the gold bump process according to claim 1, characterized in that: The shape of the gold bump is hemispherical, and the flexible contact layer is made of a material with self-recovery properties to improve the durability and long-term use stability of the contact layer.

3. The high-efficiency electrical testing method based on the gold bump process according to claim 1, characterized in that: The real-time position monitoring device uses laser interferometer technology to achieve nanometer-level precision displacement measurement and ensure high-precision feedback of micron-level alignment.

4. The high-efficiency electrical testing method based on the gold bump process according to claim 1, characterized in that: The test signal transmission device includes a low noise amplifier, a digital signal processor and a high-bandwidth transmission line.

5. The high-efficiency electrical testing method based on the gold bump process according to claim 1, wherein: The closed-loop feedback control algorithm is based on fuzzy control and adjusts the operating parameters of the test system in real time to ensure that contact errors caused by environmental changes or device deformation are effectively corrected.

6. The high-efficiency electrical testing method based on the gold bump process according to claim 1, wherein: The low-friction, high-wear-resistant coating is made of a diamond film and is prepared by a chemical vapor deposition process, and the coating thickness is 10-50 μm.

7. The high-efficiency electrical testing method based on the gold bump process according to claim 1, characterized in that: The surface of the gold bump is polished at the nano level to further reduce contact resistance and increase contact stability.

8. The high-efficiency electrical testing method based on the gold bump process according to claim 1, characterized in that: The digital signal processing module adopts low-pass filtering, Kalman filtering or wavelet transform method to improve the quality of test data and reduce noise interference.

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