Probe card MLO pad point position contraction design simulation method

Abstract

A probe card MLO pad point position contraction design simulation method is characterized by comprising the following steps that 1, a temperature field simulation model is established, and a temperature simulation result file is obtained and comprises the steps that 1.1, temperature data are actually measured; step 1.2, establishing a temperature field simulation model by adopting a finite element analysis method, modeling an air fluid part in the cavity into a solid air medium by using a steady-state thermal analysis module, and endowing the solid air with a heat transfer coefficient; calibrating heat transfer coefficients in the temperature field simulation model: a heat transfer coefficient A, a heat transfer coefficient B and a heat transfer coefficient C; 1.3, correcting and iterating the heat transfer coefficient A, the heat transfer coefficient B and the heat transfer coefficient C; 1.4, obtaining a temperature field simulation result file of the probe card at the specified high-temperature loading temperature; 2, establishing a physical field simulation model, and obtaining a simulation pad displacement result; and step 3, calculating to obtain a new pad point position coordinate for iterative production.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor chip testing, and in particular to a method for simulating point shrinkage design of a probe card organic substrate pad (MLO pad). Background Art

[0002] In CP testing, 2D MEMS vertical probe cards are widely used in chip testing due to their precise contact and high-temperature resistance. Since the probe card mainly serves to connect the bare chip and the test machine, the circuit needs to be connected through the contact of the probe to complete the test of various items of the chip. Therefore, the relative position accuracy of the ST substrate (space transformer) of the probe needle tail is very high, especially the position accuracy on the XY plane, which is collectively referred to as the needle tail contact stability. When the focus is on the needle tail contact stability, it is found that with the development of chip manufacturing process, the bump pit used for test connection of a large number of Soc chips has shown a gradual decrease, accompanied by the trend of increasing size of single die. This means that the area of the ST substrate and the area of the needle implantation area are also expanding synchronously when the probe card is designed, which poses a huge challenge to the needle tail stability in high-temperature CP testing. Due to the high-temperature test environment, the probe card as a whole will expand due to heat, and the gold-plated spot pads on the MLO (multi-layer organic substrate) of the ST substrate (referred to as the probe card MLO pad point) will produce high-temperature displacement such as Figure 1 and Figure 2 As shown, the probe tip may be misaligned or out of electrical contact, which may lead to needle burn and test abnormality.

[0003] The current mainstream 2D MEMS vertical probe card mainly restrains the thermal deformation of the probe card in high-temperature testing environments by upgrading the structural material and optimizing the structural design. However, due to the expansion of the probe implantation area and the increase in the number of pins, the ordinary optimization scheme can no longer meet the current needs. At the same time, after the development of materials science encountered a bottleneck, it is difficult to meet the technical needs of the chip testing field in a timely manner. Summary of the Invention

[0004] The purpose of the present invention is to provide a probe card MLO pad point shrinkage design simulation method to solve the technical problem of inaccurate position displacement of pads (pad points) on the MLO (multi-layer organic substrate) of the ST substrate due to high temperature.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: A probe card MLO pad point shrinkage design simulation method includes the following steps: Step 1: Establish a temperature field simulation model and obtain the temperature simulation result file, including: Step 1.1: Set multiple temperature monitoring points on the probe card, place a temperature sensor at each temperature monitoring point, and conduct an experiment on a test machine consistent with actual usage conditions to obtain the actual temperature data of the probe card under the specified high-temperature loading temperature; Step 1.2: First, use the finite element analysis method to establish a temperature field simulation model. Use the steady-state thermal analysis module to model the air fluid portion in the cavity as a solid air medium, assign a heat transfer coefficient to the solid air, create contact conditions between the solid air and the planes of each structural component, and establish a heat source model. Next, calibrate the heat transfer coefficients in the temperature field simulation model: heat transfer coefficient A, heat transfer coefficient B, and heat transfer coefficient C. The heat transfer coefficient A is the combined heat transfer coefficient of the probe card's L cover subjected to convective heat transfer from the surrounding air and contact heat transfer from the probe. The heat transfer coefficient B is the contact heat transfer coefficient between the first alloy component on the probe card and the PCB. The heat transfer coefficient C is the contact heat transfer coefficient between the second alloy component on the probe card and the PCB. Step 1.3, based on the measured temperature data of the probe card in step 1.1, the heat transfer coefficient A, heat transfer coefficient B, and heat transfer coefficient C are modified and iterated to obtain a universal standard temperature field simulation model; Step 1.4, running a simulation program with a universal standard temperature field simulation model to obtain a temperature field simulation result file of the probe card at a specified high-temperature loading temperature; Step 2: Establish a physical field simulation model and obtain the simulated pad displacement result: Use the finite element analysis method to establish a physical field simulation model, couple the above temperature field simulation result file to the physical field simulation model as the temperature load boundary condition, and run the software with the physical field simulation model to obtain the simulated pad displacement result; Step 3: Based on the above simulated pad displacement results, calculate the new pad point coordinates for iterative production; There is no strict order between steps 1.1 and 1.2, and they can be performed in parallel or in any order.

[0006] In the above scheme, the step 1.2 specifically includes: Step 1.2.1: Import the probe card's 3D structural model into the simulation software. Simplify the imported structure and remove geometric features that have no impact on the simulation calculation, such as redundant faces or corners, to improve process simulation efficiency. In step 1.2.2, use the Steady-State Thermal Analysis module to model the air flow in the cavity as a solid air medium, assign a heat transfer coefficient to the solid air, and create contact conditions between the solid air and the planes of each structural component. Simultaneously, a heat source model is created, with a volume consistent with the actual heat source in use. Step 1.2.3: Set and select the materials of each component in the temperature field simulation model according to the actual probe card material usage; Step 1.2.4, calibrate the heat transfer coefficients in the temperature field simulation model: heat transfer coefficient A, heat transfer coefficient B, and heat transfer coefficient C. Heat transfer coefficient A is the combined heat transfer coefficient of the probe card's L cover plate subjected to convective heat transfer from the surrounding air and contact heat transfer from the probes. Heat transfer coefficient B is the contact heat transfer coefficient between the first alloy structure on the probe card and the PCB. Heat transfer coefficient C is the contact heat transfer coefficient between the second alloy structure on the probe card and the PCB. In step 1.2.5, the boundary conditions are set according to the actual test environment. All exposed surfaces of the probe card in the tester direction are set to natural air convection.

[0007] In the above scheme, step 1.3 includes: In step 1.3.1, based on the measured temperature data of the probe card in step 1.1, the heat transfer coefficients A, B, and C are modified and iterated so that the simulated temperature data at each temperature monitoring point is consistent with the measured temperature data of the probe card in step 1.1 until the simulation model converges. Step 1.3.2, verifying the simulation model, includes: Step 1.3.2.1: Confirm that the temperature difference between the simulated temperature data of each temperature monitoring point and the actual temperature data of the probe card in step 1.1 does not exceed the specified range. If so, the verification is passed; if not, return to step 1.3.1; Step 1.3.2.2, by iteratively optimizing the temperature field simulation model, a universal standard temperature field simulation model is obtained.

[0008] In the above scheme, step 3 includes: Step 3.1, perform high temperature indentation verification on the same probe card as in step 1.1, including: Step 3.1.1, assemble the probe head after applying colored ink to the MLO pads of the probe card; Step 3.1.2: Load the probe card into a high-temperature environment on a test machine consistent with actual usage conditions. Step 3.1.3: After loading to the specified high temperature, perform the actual touch-down test. The number of touch-down tests is sufficient to ensure that the needle tail mark is clear. In step 3.1.4, disassemble the probe head, take a picture of the MLO pad using an electron microscope, and measure the needle mark offset at the needle tail as the actual measured data for the high-temperature needle tail offset. Step 3.1.5: Compare the high-temperature needle tail displacement measured data obtained in step 3.1.4 with the simulated pad displacement results in step 2. If the displacement error is within the specified range, the high-temperature indentation verification is passed; In step 3.2, based on the simulated pad displacement results, the new pad point coordinates are calculated for iterative production.

[0009] In the above solution, the calculation method for obtaining the new pad point coordinates in step 3 is: First, according to the formula Calculation: where A is the side length of the implant area rectangle in the X or Y direction, B is the MLO pad point, is the simulated pad displacement obtained in step 2, and Coefficient of Shrinkage is the calculated shrinkage coefficient. This formula is universal for both the X and Y directions. When the X and Y sides of the implant area are unequal, two shrinkage coefficients, Cx and Cy, are obtained. Then, the new MLO pad point coordinates are calculated by coordinate position contraction, and the formula is: .

[0010] The principle of this invention is as follows: This invention addresses the unique situation of probe cards. The actual elevated temperature environment in mass production testing of probe cards involves heating wafers in a sealed chamber to meet high-temperature testing requirements. Since convection is the primary heat transfer mechanism, this is theoretically more consistent with fluid simulation models. However, due to the complexity of the probe card structure and the large number of probes, applying fluid simulation models in mass production simulation design is clearly inadequate for design and production requirements. Therefore, the present invention employs an equivalent substitution method (i.e., a steady-state thermal module) to model the air flow portion of the cavity, excluding the solid structural components, as a solid air medium. This solid air is assigned a heat transfer coefficient and contact conditions are established between the solid air and the various structural component planes. This achieves rapid modeling and simulation, accelerates the industrial simulation process, and improves system simulation efficiency. Furthermore, in actual testing environments, the three basic principles of heat transfer essentially coexist: radiation, convection, and contact. This invention proposes a method for calibrating some simulation parameters based on measured results, aiming to balance simulation efficiency and error maximization.

[0011] The present invention has the following advantages: 1. This allows the probe card to be used stably under high-temperature conditions during CP mass production testing, avoiding frequent debugging time and saving testing costs and time costs; 2. This makes the probe card compatible with normal and high-temperature test conditions in CP mass production testing, significantly reducing the probe card procurement costs for wafer manufacturers in the testing process; 3. This invention method enables stable mass production of large-area MLO and high-pin-count probe cards, enhances the stability of the product during testing, expands the order scale, and expands product application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A structural diagram of a probe card in the background art; Figure 2 A schematic diagram of a pad on an MLO (multi-layer organic substrate) of an ST substrate in the background art undergoing high-temperature displacement; Figure 3 This is a photo of the actual high-temperature displacement of the pad on the MLO (multi-layer organic substrate) of the ST substrate in the background technology; Figure 4 Schematic diagram of the probe card structure applicable to the present invention Figure 1 , which is a schematic diagram showing the bottom and the interior of the cross section of the probe card, in which no probes are assembled; Figure 5 Schematic diagram of the probe card structure applicable to the present invention Figure 2 , which is a schematic diagram showing the top of the probe card; Figure 6 This is a photograph of a pad on an MLO (multi-layer organic substrate) using the ST substrate of the present invention after a high-temperature test.

[0013] In the above figure: 1. MLO (multi-layer organic substrate); 2. L cover; 3. PCB board; 4. first alloy structure 4; 5. second alloy structure; 6. reinforcement. DETAILED DESCRIPTION

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments: Example 1: A probe card MLO pad point shrinkage design simulation method: This probe card MLO pad point shrinkage design simulation method is applicable to the following probe card example structure Figure 4 and Figure 5 As shown, the MLO (multi-layer organic substrate) 1 is located between the L cover 2 and the PCB board 3, and the PCB board is also provided with other components such as a first structural member 4, a second structural member 5, and a reinforcement member 6.

[0015] A probe card MLO pad point shrinkage design simulation method, The specific steps include: Step 1: Establish a temperature field simulation model and obtain the temperature simulation result file, including: Step 1.1: Set multiple temperature monitoring points on the probe card, place a temperature sensor (such as a thermocouple) at each temperature monitoring point, and conduct experiments on a test machine consistent with actual usage conditions. This will obtain the actual temperature data of the probe card at the specified high-temperature loading temperature, and try to ensure that the experimental conditions are completely consistent with the actual usage conditions of the probe card product.

[0016] The temperature monitoring points are set to as many as possible, at least on the MLO, L cover, first structure 4, and second structure 5, and preferably evenly distributed across the probe area of the probe card. In this embodiment, a total of 16 temperature monitoring points are set, as shown in Table 1 below:

[0017] In the table, MLO-1 and MLO-2 are two temperature monitoring points on MLO, L-1 and L-2 are temperature monitoring points on the inner surface of the L cover facing the MLO side, PCB-1 and PCB-2 are two temperature monitoring points on the PCB board, STIFF-1 to STIFF-5 are temperature monitoring points on the reinforcement, S1 is the temperature monitoring point on the first alloy structural component, S2-1 and S2-2 are the temperature monitoring points on the second alloy structural component, and S3 is the temperature monitoring point on the third alloy structural component.

[0018] Experiments are conducted on the test machine to obtain the actual temperature data of the probe card under the specified high-temperature loading temperature. Specifically, for example, when the specified high-temperature test temperature of the probe card is 105°C, the temperature data of each temperature monitoring point under the 105°C loading condition is measured and stored.

[0019] The high-temperature loading temperature is based on the temperature of the heat source (usually the wafer heating tray) on the test machine.

[0020] Step 1.2, first use the finite element analysis method to establish a temperature field simulation model, use the steady-state thermal analysis module to model the air fluid part in the cavity as a solid air medium, assign a heat transfer coefficient to the solid air, create contact conditions between the solid air and the planes of each structural component, and establish a heat source model; then, calibrate the heat transfer coefficients in the temperature field simulation model: heat transfer coefficient A, heat transfer coefficient B and heat transfer coefficient C; the heat transfer coefficient A is the comprehensive heat transfer coefficient of the L cover of the probe card subjected to convective heat transfer from the surrounding air and contact heat transfer of the probe; the heat transfer coefficient B is the contact heat transfer coefficient between the first alloy structure on the probe card and the PCB; the heat transfer coefficient C is the contact heat transfer coefficient between the second alloy structure on the probe card and the PCB.

[0021] The step 1.2 specifically includes: In step 1.2.1, import the 3D structural model of the probe card into the simulation software. Then, simplify the imported structure and delete geometric features that have no impact on the simulation calculation, such as redundant faces or corners, to improve the efficiency of the process simulation. Available simulation software includes Abaqus, Comsol, and the free and open source engineering simulation software FreeCAD.

[0022] In step 1.2.2, use the Steady-State Thermal Analysis module to model the air flow in the cavity as a solid air medium, assign a heat transfer coefficient to the solid air, and create contact conditions between the solid air and the planes of each structural component. Simultaneously, a model of the heat source (usually a wafer heating tray) is created, with its volume consistent with the actual heat source in use. Step 1.2.3: Set and select the materials of each component in the temperature field simulation model according to the actual probe card material usage; Step 1.2.4, calibrate the heat transfer coefficients in the temperature field simulation model: heat transfer coefficient A, heat transfer coefficient B, and heat transfer coefficient C; heat transfer coefficient A is the combined heat transfer coefficient of the probe card's L cover plate subjected to convective heat transfer from the surrounding air and contact heat transfer from the probe; heat transfer coefficient B is the contact heat transfer coefficient between the first alloy structure 4 on the probe card and the PCB board 3; heat transfer coefficient C is the contact heat transfer coefficient between the second alloy structure 5 on the probe card and the PCB board 3; In step 1.2.5, the boundary conditions are set according to the actual test environment. All exposed surfaces of the probe card in the tester direction are set to natural air convection.

[0023] Step 1.3, based on the measured temperature data of the probe card in step 1.1, modify and iterate the above heat transfer coefficients A, B, and C to obtain a universal standard temperature field simulation model, specifically including: In step 1.3.1, based on the measured temperature data of the probe card in step 1.1, the heat transfer coefficients A, B, and C are modified and iterated so that the simulated temperature data at each temperature monitoring point is consistent with the measured temperature data of the probe card in step 1.1 until the simulation model converges. Step 1.3.2, verifying the simulation model, includes: Step 1.3.2.1: Confirm that the temperature difference between the simulated temperature data at each temperature monitoring point and the actual temperature data measured by the probe card in step 1.1 does not exceed the specified range (usually set to ±3°C). If so, the verification is passed; if not, return to step 1.3.1. Step 1.3.2.2, by iteratively optimizing the temperature field simulation model, a universal standard temperature field simulation model is obtained.

[0024] In step 1.4, a simulation program with a universal standard temperature field simulation model is run to obtain a temperature field simulation result file of the probe card under a specified high temperature loading temperature (105° C.).

[0025] There is no strict order between steps 1.1 and 1.2, and they can be performed in parallel or in any order.

[0026] Step 2: Establish a physical field simulation model and obtain the simulated pad displacement result: Use the finite element analysis method to establish a physical field simulation model, couple the above temperature field simulation result file to the physical field simulation model as the temperature load boundary condition, and run the software with the physical field simulation model to obtain the simulated pad displacement result; specifically including: Step 2.1, same as step 1.2.1, import the 3D model and simplify it; Step 2.2, same as step 1.2.3, set and select the materials of each component; Step 2.3: Couple the temperature field simulation result file to the physical field as a temperature load boundary condition. (Since the probe card deforms at high temperatures due to thermal stress, the probe card's temperature distribution needs to be calculated as a boundary load condition.) Step 2.4, set the screw preload boundary conditions according to the actual assembly Bom form; Step 2.5: Set the displacement constraint boundary conditions according to the actual fixing method of the test machine; Step 2.6: Start calculating and recording the simulated pad displacement data results; illustration: original pad point coordinates (x, y), high temperature simulated pad point coordinates (X, Y), then the high temperature simulated pad displacement = (Xx, Yy).

[0027] Step 3: Based on the above simulated pad displacement results, calculate the new pad point coordinates for iterative production, specifically including: Step 3.1, perform high temperature indentation verification on the same probe card as in step 1.1, including: Step 3.1.1, assemble the probe head after applying colored ink to the MLO pads of the probe card; Step 3.1.2: Load the probe card into a high-temperature environment on a test machine consistent with actual usage conditions. Step 3.1.3: After loading to the specified high temperature, perform the actual touch-down test. The number of touch-down tests is sufficient to ensure that the needle tail mark is clear. In step 3.1.4, disassemble the probe head, take a picture of the MLO pad using an electron microscope, and measure the needle mark offset at the needle tail as the actual measured data for the high-temperature needle tail offset. In step 3.1.5, compare the measured high-temperature needle tail displacement data obtained in step 3.1.4 with the simulated pad displacement results in step 2. If the displacement error is within the specified range (usually set to ±3μm), the high-temperature indentation verification is passed; In step 3.2, based on the simulated pad displacement results, the new pad point coordinates are calculated for iterative production.

[0028] The calculation method for obtaining the new pad point coordinates may specifically be: First, according to the formula Calculation: where A is the side length of the implant area rectangle in the X or Y direction, B is the MLO pad point, is the simulated pad displacement obtained in step 2, and Coefficient of Shrinkage is the calculated shrinkage coefficient. This formula is universal for both the X and Y directions. When the X and Y sides of the implant area are unequal, two shrinkage coefficients, Cx and Cy, are obtained. Then, the new MLO pad point coordinates are calculated by coordinate position contraction, and the formula is: .

[0029] For example, a calculation example of a project is as follows: Pad origin coordinates: (-17949.254, 12052.05); C x =0.999845176, C y =0.999704671 Then, the new pad point coordinates are (-17946.47502, 12048.49068) The MLO with new pad coordinates produced according to the above new coordinates is subjected to the same high temperature indentation verification experiment as step 3.1. At this time, the needle tail needle mark photo of the MLO with new pad coordinates is obtained. Figure 6 As shown. The needle tail needle marks are all inside the pad point, Figure 3 The comparison is obvious.

[0030] Example 2: A probe card MLO pad point shrinkage design simulation method: The difference from Example 1 is that the method of this embodiment is applicable to three high-temperature loading temperatures: 105°C, 115°C and 125°C. Therefore, in the above step 1.1, the temperature is loaded three times. In addition to 105°C, temperature loading of 115°C and 125°C is also required to obtain temperature data of each temperature monitoring point under the three temperature loading conditions of 105°C, 115°C and 125°C; and in step 1.3, the heat transfer coefficient A, heat transfer coefficient B and heat transfer coefficient C need to be corrected and the simulation model needs to be verified for the three temperature conditions of 105°C, 115°C and 125°C, that is, the 105°C verification mark is marked as preliminary acceptance, and then the simulation model that has passed the preliminary acceptance is used to change only the heat source temperature to 115°C, and 125°C to control other conditions unchanged. Compared with the actual measured temperature results in step 1.1, when the simulation measurement errors of all inspection points at the three test temperatures are within ±3°C, the temperature field simulation model meets the acceptance criteria.

[0031] Other aspects are the same as those of the first embodiment. The MLO pad points of the probe card produced according to this embodiment can pass high temperature tests at 105° C., 115° C., and 125° C.

[0032] In specific implementation, whether the temperature loading condition is one or three depends on the user's needs.

[0033] Example 3: A probe card MLO pad point shrinkage design simulation method: The difference from the first embodiment is that the calculation method for obtaining the new pad point coordinates is as follows: According to step 2.6, the original pad point coordinates (x, y) and the high temperature simulation pad point coordinates (X, Y) are obtained. The high temperature simulation pad displacement = (Xx, Yy). We perform the following calculations on all pad point coordinates to obtain the new coordinates after shrinkage: .

[0034] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A probe card MLO pad point shrinkage design simulation method, characterized by: The following steps are involved: Step 1: Establish a temperature field simulation model and obtain the temperature simulation result file, including: Step 1.1: Set multiple temperature monitoring points on the probe card, place a temperature sensor at each temperature monitoring point, and conduct an experiment on a test machine consistent with actual usage conditions to obtain the actual temperature data of the probe card under the specified high-temperature loading temperature; Step 1.2: First, use the finite element analysis method to establish a temperature field simulation model. Use the steady-state thermal analysis module to model the air fluid portion in the cavity as a solid air medium, assign a heat transfer coefficient to the solid air, create contact conditions between the solid air and the planes of each structural component, and establish a heat source model. Next, calibrate the heat transfer coefficients in the temperature field simulation model: heat transfer coefficient A, heat transfer coefficient B, and heat transfer coefficient C. The heat transfer coefficient A is the combined heat transfer coefficient of the probe card's L cover subjected to convective heat transfer from the surrounding air and contact heat transfer from the probe. The heat transfer coefficient B is the contact heat transfer coefficient between the first alloy component on the probe card and the PCB. The heat transfer coefficient C is the contact heat transfer coefficient between the second alloy component on the probe card and the PCB. Step 1.3, based on the measured temperature data of the probe card in step 1.1, the heat transfer coefficient A, heat transfer coefficient B, and heat transfer coefficient C are modified and iterated to obtain a universal standard temperature field simulation model; Step 1.4, running a simulation program with a universal standard temperature field simulation model to obtain a temperature field simulation result file of the probe card at a specified high-temperature loading temperature; Step 2: Establish a physical field simulation model and obtain the simulated pad displacement result: Use the finite element analysis method to establish a physical field simulation model, couple the above temperature field simulation result file to the physical field simulation model as the temperature load boundary condition, and run the software with the physical field simulation model to obtain the simulated pad displacement result; Step 3: Based on the above simulated pad displacement results, calculate the new pad point coordinates for iterative production; There is no strict order between steps 1.1 and 1.2, and they can be performed in parallel or in any order.

2. The probe card MLO pad point shrinkage design simulation method according to claim 1, characterized in that: The step 1.2 specifically includes: Step 1.2.1: Import the probe card's 3D structural model into the simulation software. Simplify the imported structure and remove geometric features that have no impact on the simulation calculation, such as redundant faces or corners, to improve process simulation efficiency. In step 1.2.2, use the Steady-State Thermal Analysis module to model the air flow in the cavity as a solid air medium, assign a heat transfer coefficient to the solid air, and create contact conditions between the solid air and the planes of each structural component. Simultaneously, a heat source model is created, with a volume consistent with the actual heat source in use. Step 1.2.3: Set and select the materials of each component in the temperature field simulation model according to the actual probe card material usage; Step 1.2.4, calibrate the heat transfer coefficients in the temperature field simulation model: heat transfer coefficient A, heat transfer coefficient B, and heat transfer coefficient C. Heat transfer coefficient A is the combined heat transfer coefficient of the probe card's L cover plate subjected to convective heat transfer from the surrounding air and contact heat transfer from the probes. Heat transfer coefficient B is the contact heat transfer coefficient between the first alloy structure on the probe card and the PCB. Heat transfer coefficient C is the contact heat transfer coefficient between the second alloy structure on the probe card and the PCB. In step 1.2.5, the boundary conditions are set according to the actual test environment. All exposed surfaces of the probe card in the tester direction are set to natural air convection.

3. The probe card MLO pad point shrinkage design simulation method according to claim 1, characterized in that: The step 1.3 includes: In step 1.3.1, based on the measured temperature data of the probe card in step 1.1, the heat transfer coefficients A, B, and C are modified and iterated so that the simulated temperature data at each temperature monitoring point is consistent with the measured temperature data of the probe card in step 1.1 until the simulation model converges. Step 1.3.2, verifying the simulation model, includes: Step 1.3.2.1: Confirm that the temperature difference between the simulated temperature data of each temperature monitoring point and the actual temperature data of the probe card in step 1.1 does not exceed the specified error range. If so, the verification is passed; if not, return to step 1.3.1; Step 1.3.2.2, by iteratively optimizing the temperature field simulation model, a universal standard temperature field simulation model is obtained.

4. The probe card MLO pad point shrinkage design simulation method according to claim 1, characterized in that: The step 3 comprises: Step 3.1, perform high temperature indentation verification on the same probe card as in step 1.1, including: Step 3.1.1, assemble the probe head after applying colored ink to the MLO pads of the probe card; Step 3.1.2: Load the probe card into a high-temperature environment on a test machine consistent with actual usage conditions. Step 3.1.3: After loading to the specified high temperature, perform the actual touch-down test. The number of touch-down tests is sufficient to ensure that the needle tail mark is clear. In step 3.1.4, disassemble the probe head, take a picture of the MLO pad using an electron microscope, and measure the needle mark offset at the needle tail as the actual measured data for the high-temperature needle tail offset. Step 3.1.5: Compare the high-temperature needle tail displacement measured data obtained in step 3.1.4 with the simulated pad displacement results in step 2. If the displacement error is within the specified range, the high-temperature indentation verification is passed; In step 3.2, based on the simulated pad displacement results, the new pad point coordinates are calculated for iterative production.

5. The probe card MLO pad point shrinkage design simulation method according to claim 1 or 4, characterized in that: The calculation method for obtaining the new pad point coordinates in step 3 is: First, according to the formula Calculation: where A is the side length of the implant area rectangle in the X or Y direction, B is the MLO pad point, is the simulated pad displacement obtained in step 2, and Coefficient of shrinkage is the calculated shrinkage coefficient. This formula is universal for both the X and Y directions. When the X and Y side lengths of the implant area are unequal, two shrinkage coefficients, Cx and Cy, are obtained. Then, the new MLO pad point coordinates are calculated by coordinate position contraction, and the formula is: 。

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