A socket probe impedance analysis method

Abstract

This invention discloses a method for analyzing SOCKET probe impedance. It identifies and obtains the influencing factors affecting SOCKET probe impedance, deriving a first variable. Using 3D electromagnetic simulation technology, a scanning simulation is performed on this first variable to obtain a large amount of simulated probe impedance data. Based on the relationship between the first variable and the simulated SOCKET probe impedance, a second variable is formed. Regression analysis is performed on all variables to obtain the linear coefficients of each variable, resulting in a mathematical model for calculating the SOCKET probe impedance. This invention provides a method for analyzing SOCKET probe impedance by obtaining a large set of multivariate probe impedance data through 3D electromagnetic simulation. Based on this, variables are expanded, and then linear regression is performed on all variables to obtain a mathematical model for calculating probe impedance. This allows subsequent estimation and optimization of probe impedance to be performed simply by substituting parameters.

Description

Technical Field

[0001] This invention relates to the field of chip testing technology, and more specifically, to a method for SOCKET probe impedance analysis. Background Technology

[0002] A chip, a general term for semiconductor components, is the core of electronic devices and is crucial to electronic products. During chip manufacturing, testing is necessary to ensure yield and improve chip quality. With technological advancements and increasing demands, electronic devices are taking on more and heavier functions, leading to increased complexity in chip packaging. Demands for high lifespan, low impedance, and high speed / frequency are becoming increasingly important for advanced chip testing. To achieve fast and efficient chip testing, a fixture—a chip test socket—is typically used, capable of working with both automated and manual testing equipment.

[0003] A chip test socket, also known as a chip test receptacle, is a connector socket that connects a chip to a PCB board. Its main function is to meet the connection requirements between the chip's pins and the PCB test board. A chip test socket mainly consists of three parts: the upper layer holds and secures the chip or connector under test; the middle layer contains probes for electrical connection; and the lower layer secures the socket to the test circuit board via a structural design. Essentially, a chip test socket is an extension of the chip's pins, enabling electrical connection without soldering, and plays a crucial role in bridging the gap between the chip and the PCB in complex PCB manufacturing processes.

[0004] The SOCKET probe used for electrical connection has two elastic contact ends and a fixed-length metal column in the middle. The middle section is the part of the SOCKET probe with the largest diameter and the lowest impedance. Therefore, the impedance optimization of the SOCKET probe usually focuses on the impedance optimization of the middle section.

[0005] Factors affecting socket probe impedance include intrinsic factors such as probe spacing and probe diameter, as well as external factors such as the socket structure and material. In existing technologies, projects aimed at optimizing and improving socket probe impedance often employ complex 3D electromagnetic simulation methods to evaluate and verify each optimization scheme individually, leading to…

[0006] 1. It requires highly skilled technical personnel. 3D electromagnetic simulation personnel need to model and simulate the detailed structure and material properties of the SOCKET probe in the evaluation and improvement project. They also need to determine the range of values ​​for variables, etc. 3D simulation personnel need to have a solid theoretical foundation and simulation experience to complete this task.

[0007] 2.3D electromagnetic simulation software licenses are expensive, and the number of devices that can use them is often limited.

[0008] Therefore, for SOCKET probe impedance and evaluation improvement projects, the higher the involvement and the stronger the accompanying effect of 3D electromagnetic simulation, or the more targeted the application of 3D electromagnetic simulation, the more repetitive the work of 3D electromagnetic simulation will be, and the lower the efficiency of 3D electromagnetic simulation software. Given the high requirements of 3D electromagnetic simulation for technical personnel and the high cost of software, it will ultimately lead to a decrease in the efficiency of SOCKET probe impedance optimization. Summary of the Invention

[0009] To improve the efficiency of SOCKET probe impedance optimization, this invention provides a SOCKET probe impedance analysis method. This method obtains a large set of multivariate probe impedance data through 3D electromagnetic simulation, expands the variables based on this data, and then performs linear regression fitting on all variables to obtain a mathematical model for calculating probe impedance. This allows subsequent estimations of probe impedance and consideration of optimization schemes to be performed simply by substituting parameters, making the process simple, convenient, and highly accurate. The 3D electromagnetic simulation work is completed in the early stages of SOCKET probe impedance optimization, reducing repetitive work caused by later case-by-case simulations. This improves the efficiency of 3D electromagnetic simulation software and lowers the simulation skills required for later impedance optimization design personnel, thereby increasing the efficiency of SOCKET probe impedance optimization.

[0010] The technical solution of the present invention is as follows:

[0011] A method for analyzing SOCKET probe impedance is proposed. This method identifies and obtains the influencing factors affecting SOCKET probe impedance, derives a first variable, and uses 3D electromagnetic simulation technology to perform a scanning simulation on the first variable, obtaining a large amount of probe impedance simulation data. Based on the relationship between the first variable and the simulated SOCKET probe impedance, a second variable is formed. Regression analysis is performed on all variables to obtain the linear coefficients of each variable, and a mathematical model of SOCKET probe impedance is obtained.

[0012] The process of obtaining the mathematical model for the above-mentioned SOCKET probe impedance analysis method includes:

[0013] Step S1. Establish multiple SOCKET probe simulation models based on the theoretical SOCKET probe impedance influencing factors, and verify the SOCKET probe impedance influencing factors through 3D electromagnetic simulation.

[0014] Step S2. Based on the principle of impedance influence of SOCKET probe impedance, set the first variable of SOCKET probe accordingly, and perform multiple sets of simulations by changing the parameter settings of the first variable.

[0015] Step S3. Perform batch scanning of SOCKET probe simulations, obtain the probe impedance of each group of simulations, and compile them into a table;

[0016] Step S4. Analyze the relationship between the first variable and the probe impedance to obtain the second variable;

[0017] Step S5. Combine the first variable and the second variable to derive the calculation formula for the probe impedance drift model.

[0018] The above-mentioned SOCKET probe impedance analysis method includes the following first variables: probe diameter, probe spacing, SOCKET dielectric, long side dimension of SOCKET probe rectangular socket, and short side dimension of SOCKET probe rectangular socket. The second variables are the reciprocal of probe diameter, reciprocal of SOCKET dielectric, reciprocal of probe spacing, reciprocal of long side dimension of SOCKET probe rectangular socket, reciprocal of short side dimension of SOCKET probe rectangular socket, reciprocal of the product of long side dimension of SOCKET probe rectangular socket and short side dimension of SOCKET probe rectangular socket, and the square root of SOCKET dielectric.

[0019] Furthermore, the probe impedance is negatively correlated with the probe diameter and the socket medium, and positively correlated with the probe spacing, the long side dimension of the socket rectangular socket, and the short side dimension of the socket rectangular socket.

[0020] The aforementioned SOCKET probe impedance analysis method uses a controlled variable method to perform a scanning simulation of the first variable, wherein the long side dimension and the short side dimension of the SOCKET probe rectangular socket are related variables that change simultaneously.

[0021] Furthermore, the first change in the controlled electrical quantity is a constant value, so that the array of changing variables forms an arithmetic sequence.

[0022] In the aforementioned SOCKET probe impedance analysis method, when performing linear regression analysis on the first variable, the Y-axis value is used as the probe impedance value, and the X-axis value is used as the variable value.

[0023] The aforementioned SOCKET probe impedance analysis method uses a SOCKET probe composed of three cylindrical sections. The two end contact points are elastic cylinders with smaller diameters, while the middle section is a cylinder with a larger diameter. The SOCKET probe is connected to the SOCKET base via a socket, which is a rectangular cylindrical structure that connects two adjacent SOCKET probes.

[0024] Furthermore, the long side dimension of the SOCKET probe rectangle is expressed as probe spacing + probe diameter + length of the socket; the short side dimension of the SOCKET probe rectangle is expressed as probe diameter + length of the socket.

[0025] The mathematical model for the probe impedance in the above-mentioned SOCKET probe impedance analysis method is as follows:

[0026]

[0027] Where Z is the probe impedance in ohms; D is the probe diameter in millimeters, ranging from 0.2032 mm to 0.2832 mm; DK is the SOCKET dielectric, a constant ranging from 2.5 to 5.5; S is the probe spacing in millimeters, ranging from 0.3 mm to 0.5023 mm; L is the long side dimension of the SOCKET probe rectangular socket in millimeters, ranging from 0.63 mm to 1.827 mm; and W is the short side dimension of the OCKET probe rectangular socket in millimeters, ranging from 0.3302 mm to 1.3246 mm.

[0028] Based on theoretical and experimental results, the factors influencing probe impedance include the relative permittivity (SOCKET DK), SOCKET structure, probe diameter, and probe spacing. The principle of optimizing probe impedance by changing the relative permittivity is to adjust the relative permittivity of the SOCKET material (dielectric), thereby altering the parasitic capacitance around the probe and thus affecting the probe impedance. The SOCKET structure can be designed in various styles; its principle for changing probe impedance is to control the relative distribution between the dielectric and air around the probe to influence the probe's parasitic capacitance, thus affecting the probe impedance. Adjusting the probe diameter affects the coupling area between the probe and ground, thereby changing the probe's parasitic capacitance and thus affecting the probe impedance. Similarly, adjusting the probe spacing affects the coupling distance between the probe and ground, thereby changing the probe's parasitic capacitance and thus affecting the probe impedance. In summary, optimizing these four factors affecting probe impedance all involve changing the parameters of these factors to alter the probe's parasitic capacitance, ultimately changing the probe impedance.

[0029] Due to the miniaturization requirements of electronic device circuits and advancements in manufacturing processes, the size of chips and connectors is gradually shrinking, while the number of pins is increasing. This leads to increasingly smaller pin pitches on chips and connectors, while simultaneously, efficiency demands result in rapidly increasing signal transmission rates. Probes are extensions of pins, and the reduction in pin pitch directly affects the reduction in probe pitch. Probe impedance decreases as probe pitch shrinks, leading to a decline in probe signal transmission performance and making it difficult for probes to meet the demands of high-speed signal testing. However, probe pitch is limited by chip design and cannot be changed during probe impedance optimization; therefore, changes to probe pitch are rarely considered in probe impedance optimization.

[0030] Having identified the factors influencing probe impedance, multiple SOCKET probe simulation models were established, and 3D electromagnetic simulations were performed to verify these factors. Using the four influencing factors as variables, the most important or most significantly effective factor affecting probe impedance was determined through the control of a single variable.

[0031] Verification through 3D electromagnetic simulation showed that adjusting the probe diameter can reduce probe return loss, but this is insufficient to meet the testing requirements of high-speed signals. Directly adjusting the parameters of influencing factors yielded limited optimization results; therefore, structural factors were considered. By changing the structure—from a circular to a rectangular cylindrical connector in the middle of the probe—and altering the length and width of the rectangular connector, simulations with different probe models showed a significant reduction in probe return loss, demonstrating substantial optimization and improvement, thus meeting the testing requirements of high-speed signals.

[0032] After verification through 3D electromagnetic simulation, the controllable and achievable attributes were defined as the first variables for probe impedance optimization. These first variables are probe diameter, probe spacing, SOCKET dielectric, the long side dimension of the SOCKET probe rectangular socket, the short side dimension of the SOCKET probe rectangular socket, and the probe mid-section length. The probe diameter is the diameter of the SOCKET probe mid-section; the probe spacing is equivalent to the spacing between the pins of the chip or connector, which can be represented as the distance between the centers of the contact points at both ends of the two SOCKET probes; the SOCKET dielectric is essentially represented by the DK (relative permittivity) of the SOCKET material; the long side dimension of the SOCKET probe rectangular socket can be represented as the probe spacing + probe diameter + the dimension along the long side of the socket; the short side dimension of the SOCKET probe rectangular socket can be represented as the probe diameter + the dimension along the short side of the socket; the probe mid-section length is a fixed parameter for different SOCKET probe models and is not adjusted. After changing the cylindrical socket structure of the probe mid-section from circular to rectangular, it is evident that this structural adjustment results in a significant optimization effect for each SOCKET probe model.

[0033] The changes to the long side and short side dimensions of the SOCKET probe rectangular socket essentially control the equivalent DK of the medium surrounding the SOCKET probe. The conditions for their values ​​need to be consistent with the actual situation. The minimum value must ensure that the SOCKET probe can be inserted and used normally, and the maximum value must ensure that it does not affect the impedance of other signal probes, so that the optimization scheme can be applied in practice.

[0034] The range of variation for each variable in the first variable is set, and then the only variable that changes is locked for simulation. After multiple batch scans, the probe impedance under different combinations of variable parameters is obtained. Among them, the long side dimension and the short side dimension of the SOCKET probe rectangular socket are linked variables, and they change together. The ratio of the long side dimension to the short side dimension of the SOCKET probe rectangular socket is used as the variable parameter.

[0035] After observing the variable parameters and probe impedance after multiple batch scans, a second variable is obtained based on the relationship between the variable parameters and probe impedance. The second variable is the reciprocal of the probe diameter, the reciprocal of the SOCKET medium, the reciprocal of the probe spacing, the reciprocal of the long side dimension of the SOCKET probe rectangular socket, the reciprocal of the short side dimension of the SOCKET probe rectangular socket, the reciprocal of the product of the long side dimension and the short side dimension of the SOCKET probe rectangular socket, and the square root of the SOCKET medium.

[0036] When considering optimization schemes for probe impedance, such as determining whether the SOCKET used for current chip testing meets design requirements, the first variable is the probe mid-section length, which is usually a constant length according to the conventional design of the actual situation; the probe spacing is determined by the spacing between the pins of the chip or connector, and is also a constant variable; therefore, the actual first variable is the SOCKET medium, the long side dimension of the SOCKET probe rectangular socket, and the short side dimension of the SOCKET probe rectangular socket.

[0037] According to the above-described scheme, this invention obtains a large set of probe impedance data for influencing factors through scanning simulation. Based on this, a mathematical model of probe impedance change is obtained by fitting multiple variables through linear regression. Its beneficial effects are as follows:

[0038] 1. The derived mathematical model is simple and highly accurate. In the subsequent evaluation of probe impedance optimization schemes or the process of considering probe impedance, the personnel only need to substitute the variable values ​​corresponding to the influencing factors in the mathematical model into the formula to calculate, so as to predict the magnitude of the probe impedance when using the general optimization scheme under the existing conditions. The skill requirements of the personnel are greatly reduced. It is possible to obtain results with minimal error without performing a large number of complex and time-consuming 3D electromagnetic simulations, which is conducive to the advancement of optimization scheme work.

[0039] 2. The mathematical model is obtained by combining multiple variables, and it is compatible with different probe impedance influencing factors, including probe diameter, probe spacing, different SOCKET materials and other parameters. This directly leads to a wider range of consideration, higher accuracy and wider applicability when performing subsequent optimization prediction, evaluation of optimization schemes and other operations. It can quickly obtain the evaluation direction of optimization schemes with single or multiple variables to meet the required probe impedance requirements. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a partial data table for the first and second variables.

[0042] Figure 2 This is a partial data table comparing the calculated values ​​obtained from the mathematical model after linear regression fitting with the original simulation calculated values. Detailed Implementation

[0043] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0044] A method for analyzing SOCKET probe impedance is proposed. Based on theoretical preliminary assessment of the factors influencing SOCKET probe impedance, a first variable is identified. Multiple SOCKET probe simulation models are established using 3D electromagnetic simulation technology to verify the effect of the first variable. After verification, a scanning simulation is performed on the first variable to obtain a large amount of probe impedance simulation data. Based on the relationship between the first variable and SOCKET probe impedance, regression analysis is performed sequentially with SOCKET probe impedance as Y and any variable as X. Regression analysis is then performed on all variables to obtain the linear coefficients of each variable, thereby deriving the calculation formula for the SOCKET probe impedance drift model.

[0045] The specific implementation process is as follows.

[0046] Step S1. Establish multiple SOCKET probe simulation models based on the theoretical SOCKET probe impedance influencing factors, and verify the SOCKET probe impedance influencing factors through 3D electromagnetic simulation.

[0047] Theoretically, the factors affecting the impedance of a socket probe include the relative permittivity (socket DK), the socket structure, the probe diameter, and the probe spacing. Based on these factors, the following socket probe simulation model is established.

[0048] First probe simulation model: The probe diameter is 0.2832 mm, the SOCKET dielectric (relative permittivity of SOCKET material) is 4.5, the probe spacing is 0.35 mm, and the diameter of the SOCKET probe circular socket is 0.3086 mm.

[0049] The second probe simulation model has a probe diameter of 0.2032 mm, a SOCKET dielectric (relative permittivity of the SOCKET material) of 4.5, a probe spacing of 0.35 mm, and a SOCKET probe circular socket diameter of 0.2286 mm.

[0050] The third probe simulation model has the following characteristics: probe diameter of 0.2032 mm, SOCKET dielectric (relative permittivity of SOCKET material) of 4.5, probe spacing of 0.35 mm, long side dimension of SOCKET probe rectangular socket of 0.6802 mm, and short side dimension of SOCKET probe rectangular socket of 0.3302 mm.

[0051] The SOCKET probe consists of three cylindrical sections. The two end contact points are elastic cylinders with smaller diameters, while the middle section is a cylinder with a larger diameter. The SOCKET probe is connected to the SOCKET base (i.e., the lower structure) via a socket, with one socket connecting two adjacent SOCKET probes. In this embodiment, the sockets of the first and second probe simulation models are cylindrical structures, while the socket of the third probe simulation model is a rectangular columnar structure with the same height as the middle section.

[0052] The first, second, and third probe simulation models were subjected to 3D electromagnetic simulation to obtain the TDR (used to test the voltage amplitude of the reflected wave, from which the impedance value can be obtained) and return loss of the three probe simulation models. The magnitude of the probe differential impedance and the return loss were considered and verified together.

[0053] Verification results:

[0054] The differential impedance of the probe in the first probe simulation model is 53 ohms, and the probe return loss is -3dB@10GHz (that is, when the signal frequency is 10GHz, the probe return loss is -3dB, the same below). The impedance fluctuation range is large, resulting in poor passive performance of the probe.

[0055] The second probe simulation model has a probe differential impedance of 72 ohms and a probe return loss of -7.5dB@10GHz, which is a significant improvement over the first probe simulation model, but still cannot meet the requirements of high-speed signal testing.

[0056] The third probe simulation model has a probe differential impedance of 99 ohms and a probe return loss of -28dB@10GHz. Compared with the first and second probe simulation models, the impedance properties of the third probe simulation model are greatly improved, which can meet the requirements of high-speed signal testing.

[0057] The above verification confirms that all the aforementioned influencing factors have a certain impact on SOCKET probes. When optimizing the impedance of SOCKET probes, adjustments can be made to address these influencing factors. 3D electromagnetic simulation clearly shows that while changing the diameter and spacing of SOCKET probes can optimize their impedance, it is difficult to achieve good optimization results. In contrast, modifying the SOCKET probe structure yields better optimization results. Considering practical reasons such as the fixed spacing between chip or connector pins and the inability to reduce the size of SOCKET probe manufacturing processes, changes to the SOCKET structure should be prioritized when considering SOCKET probe impedance optimization schemes.

[0058] Step S2. Set the first variable of the SOCKET probe, and perform multiple simulations by changing the parameter settings of the first variable.

[0059] The first variable, derived from the factors influencing SOCKET probe impedance, serves as the basis for the optimization calculation. This first variable represents the performance attributes of the influencing factors. It includes the probe diameter, probe spacing, SOCKET dielectric, the long side dimension of the SOCKET probe rectangular socket, the short side dimension of the SOCKET probe rectangular socket, and the probe mid-section length. In this embodiment, the probe diameter ranges from 0.2032 mm to 0.2832 mm, the probe spacing ranges from 0.3 mm to 0.5 mm, the relative permittivity of the SOCKET dielectric ranges from 2.5 to 5.5, the long side dimension of the SOCKET probe rectangular socket ranges from (probe diameter + probe spacing + 0.0127 mm) to (probe diameter + probe spacing + 1.0414 mm), the short side dimension ranges from (probe diameter + 0.0127 mm) to (probe diameter + 1.0414 mm), and the probe mid-section length is constant.

[0060] Step S3. Perform batch scanning of SOCKET probe simulations, obtain the probe impedance of each group of simulations, and compile them into a table.

[0061] In this embodiment, the scanning interval within the range of values ​​for each variable is 2 mils. The smaller the scanning interval, the more scans are performed, the more continuous the data changes, and the more workload is required. The specific requirements must be determined based on the actual situation.

[0062] A set of fixed variable parameters was used to perform a single-set simulation to form basic simulation data. The fixed variable parameters were: probe diameter 0.2832 mm, SOCKET dielectric (relative permittivity of SOCKET material) 2.5, probe spacing 0.35 mm, long side dimension of SOCKET probe rectangular socket 0.7602 mm, and short side dimension of SOCKET probe rectangular socket 0.4102 mm. After simulation, the probe impedance was found to be 81.30 ohms. This set of parameter data is the basic simulation data.

[0063] Based on the basic simulation data, a first independent variable is set. In this embodiment, the first independent variable is the product of the long side dimension and the short side dimension of the SOCKET probe rectangular socket, or in other words, both change simultaneously to ensure that they simultaneously meet the requirement of covering two adjacent SOCKET probes. For the independent variable, the long side dimension of the SOCKET probe rectangular socket is based on (probe diameter + probe spacing + 0.0254 mm), and the short side dimension of the SOCKET probe rectangular socket is based on (probe diameter + 0.0254 mm), with the values ​​gradually increased in batches for simulation. Specifically, the single increase in the independent variables is a constant value, making the array of independent variables an arithmetic sequence. In this embodiment, the single change in the long side dimension and the short side dimension of the SOCKET probe rectangular socket is 2 mils. The range of change for the long side dimension of the SOCKET probe rectangular socket is 0.7602 mm - 1.6745 mm, and the range of change for the short side dimension is 0.4101 mm - 1.3246 mm. Keeping other first variables such as probe spacing, probe diameter, and SOCKET dielectric constant, multiple sets of simulation results and SOCKET probe impedance values ​​are obtained.

[0064] Similar to the process of independent variables described above, the first variable corresponding to the independent variable is continuously changed, and a scanning simulation is performed within the range of the first variable to obtain multiple sets of simulation data. These data are then organized into a table for later summarization and use, as shown in the table below.

[0065]

[0066] Step S4. Analyze the relationship between the first variable and the probe impedance to obtain the second variable.

[0067] Analyzing the relationship between the first variable and probe impedance allows us to observe their relative relationship through a graph. This provides a rough correlation: probe impedance is negatively correlated with probe diameter and socket dielectric, and positively correlated with probe spacing, the long side dimension of the socket, and the short side dimension of the socket. Based on this correlation, we expand the variable pool by adding the reciprocal of probe diameter, the reciprocal of socket dielectric, the reciprocal of probe spacing, the reciprocal of the long side dimension of the socket, the reciprocal of the short side dimension of the socket, the reciprocal of the product of the long and short side dimensions of the socket, and the square root of the socket dielectric as second variables. This improves the accuracy and precision of subsequent fitting and the predictive accuracy of the formula. Before obtaining these specific second variables, we experiment with various second variables based on conventional theory and mathematical calculations. We remove second variables that do not improve the predictive accuracy of the formula or whose improvement does not meet the standards, ultimately obtaining the specific variables described above. Specifically, such as Figure 1 As shown.

[0068] Step S5. Combine the first variable and the second variable to derive the calculation formula for the probe impedance drift model.

[0069] By combining the first and second variables, a mathematical formula can be derived to calculate their correlation with probe impedance. In this embodiment, regression analysis is used. According to step S3, multiple sets of simulation data for a single independent variable are obtained. Plotting these data graphically yields curves with similar shapes. Linear regression analysis is then performed on this curve to obtain the linear coefficients of the single variable. In the linear regression analysis, the Y-axis value is used as the probe impedance, and the X-axis value as the independent variable. Specifically, in this embodiment, the linear coefficients of the first and second variables are as follows:

[0070] The intercept coefficient value obtained after regression analysis of all data is 200.0714. When the cutoff point of the probe impedance is 200.0714, the linear coefficient of the probe diameter is -387.219, the linear coefficient of the SOCKET medium is -15.5433, the linear coefficient of the reciprocal of the probe diameter is -3.28434, the linear coefficient of the reciprocal of the SOCKET medium is 69.80133, the linear coefficient of the square root of the SOCKET medium is 75.01527, the linear coefficient of the reciprocal of the probe spacing is -36.0589, the linear coefficient of the reciprocal of the long side dimension of the SOCKET probe rectangular socket is 23.72996, the linear coefficient of the reciprocal of the short side dimension of the SOCKET probe rectangular socket is -16.0402, and the linear coefficient of the reciprocal of the product of the long side dimension and the short side dimension of the SOCKET probe rectangular socket is 2.076226.

[0071] Based on the cutoff point of the probe impedance and the linear coefficients of each variable, the formula for calculating the probe impedance drift model is obtained:

[0072]

[0073] Where Z is the probe impedance in ohms; D is the probe diameter in millimeters, ranging from 0.2032 mm to 0.2832 mm; DK is the socket dielectric, a constant ranging from 2.5 to 5.5; S is the probe spacing in millimeters, ranging from 0.3 mm to 0.5023 mm; L is the long side dimension of the socket rectangular opening of the socket probe, in millimeters, ranging from 0.63 mm to 1.827 mm; and W is the short side dimension of the socket rectangular opening of the socket probe, in millimeters, ranging from 0.3302 mm to 1.3246 mm. The range of values ​​in the above formula is also the applicable range of the formula for calculating the probe impedance drift model. Comparison with 3D electromagnetic simulation shows that the error range of this formula is within 3%, indicating high accuracy. Figure 2 As shown.

[0074] Once the calculation formula is obtained, subsequent calculations can directly apply this formula to obtain the corresponding probe impedance. This allows for a rapid assessment of the impact of changes in a certain variable parameter on the probe impedance, whether the corresponding probe impedance requirements can be met, and thus a quick evaluation of improvement plans.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for SOCKET probe impedance analysis, characterized in that, The factors affecting the SOCKET probe impedance were identified and obtained, leading to the first variable. Using 3D electromagnetic simulation technology, a scanning simulation was performed on the first variable to obtain a large amount of probe impedance simulation data. Based on the relationship between the first variable and the simulated SOCKET probe impedance, a second variable was formed. Regression analysis was performed on all variables to obtain the linear coefficients of each variable, and a mathematical model of the SOCKET probe impedance was obtained. The process of obtaining a mathematical model includes: Step S1. Establish multiple SOCKET probe simulation models based on the theoretical SOCKET probe impedance influencing factors, and verify the SOCKET probe impedance influencing factors through 3D electromagnetic simulation. Step S2. Based on the principle of impedance influence of SOCKET probe, set the first variable of SOCKET probe accordingly, and perform multiple simulations by changing the parameter settings of the first variable. Step S3. Perform batch scanning of SOCKET probe simulations, obtain the probe impedance of each group of simulations, and compile them into a table; Step S4. Analyze the relationship between the first variable and the probe impedance to obtain the second variable; Step S5. Combine the first variable and the second variable to derive the calculation formula for the probe impedance drift model; When performing linear regression analysis, the Y-axis value is used as the probe impedance and the X-axis value is used as the independent variable. The first variables include probe diameter, probe spacing, SOCKET medium, the long side dimension of the SOCKET probe rectangular socket, and the short side dimension of the SOCKET probe rectangular socket. The second variables are the reciprocal of the probe diameter, the reciprocal of the SOCKET medium, the reciprocal of the probe spacing, the reciprocal of the long side dimension of the SOCKET probe rectangular socket, the reciprocal of the short side dimension of the SOCKET probe rectangular socket, the reciprocal of the product of the long side dimension and the short side dimension of the SOCKET probe rectangular socket, and the square root of the SOCKET medium. The mathematical model for probe impedance is: ； Where Z is the probe impedance in ohms; D is the probe diameter in millimeters, ranging from 0.2032 mm to 0.2832 mm; DK is the SOCKET dielectric, a constant ranging from 2.5 to 5.5; S is the probe spacing in millimeters, ranging from 0.3 mm to 0.5023 mm; L is the long side dimension of the SOCKET probe rectangular socket in millimeters, ranging from 0.63 mm to 1.827 mm; and W is the short side dimension of the OCKET probe rectangular socket in millimeters, ranging from 0.3302 mm to 1.3246 mm.

2. The SOCKET probe impedance analysis method according to claim 1, characterized in that, The probe impedance is negatively correlated with the probe diameter and the socket medium, and positively correlated with the probe spacing, the long side dimension of the socket rectangular socket, and the short side dimension of the socket rectangular socket.

3. The SOCKET probe impedance analysis method according to claim 1, characterized in that, The first variable is simulated by scanning using the controlled variable method, where the long side dimension and the short side dimension of the SOCKET probe rectangular socket are related variables that change simultaneously.

4. The SOCKET probe impedance analysis method according to claim 3, characterized in that, The first variable being controlled has a constant value for each single change, so that the array of variables that are changing forms an arithmetic sequence.

5. The SOCKET probe impedance analysis method according to claim 1, characterized in that, When performing linear regression analysis on the first variable, the Y-axis value is used as the probe impedance value, and the X-axis value is used as the variable value.

6. The SOCKET probe impedance analysis method according to claim 1, characterized in that, The SOCKET probe consists of three cylindrical sections. The two end contact points are flexible cylinders with smaller diameters, while the middle section is a cylinder with a larger diameter. The SOCKET probe is connected to the SOCKET base via a socket, which is a rectangular cylindrical structure that connects two adjacent SOCKET probes.

7. The SOCKET probe impedance analysis method according to claim 6, characterized in that, The long side dimension of a SOCKET probe rectangle is expressed as probe spacing + probe diameter + length of the socket along the long side; the short side dimension of a SOCKET probe rectangle is expressed as probe diameter + length of the socket along the short side.

Images