Method, device and system for measuring Eoss parameter of MOS (Metal Oxide Semiconductor) transistor

Abstract

The invention discloses a method, a device and a system for measuring Eoss parameters of an MOS (Metal Oxide Semiconductor) tube. Relates to the field of power devices, and solves the problem of low efficiency of measuring Eoss parameters by combining an LCR meter with a high-voltage power supply. According to the invention, the parasitic capacitor of the MOS tube is charged in a constant current mode and a constant voltage mode, and the target drain-source voltage and the target leakage current between the drain electrode and the source electrode are monitored at the same time, so that the Eoss parameter is calculated. By controlling the charging of the constant current source, the situation that parameters need to be frequently adjusted and set, and the test efficiency is influenced is avoided; by collecting voltage data at regular time, the collection precision and the number of sampling points are improved; the measurement precision of the Eoss parameters is improved; the automatic and rapid measurement of the Eoss parameters is realized, an LCR meter is not needed, manual operation errors are reduced, and the test speed is increased.

Description

Technical Field

[0001] The present application relates to the field of power devices, and in particular to a method, device and system for measuring the Eoss parameters of a MOS tube. Background Art

[0002] Before leaving the factory, power chips need to undergo online testing of more than 20 parameters to confirm whether they are good. The time taken to measure each parameter is directly related to the efficiency of the entire test line. Among them, the Eoss parameter refers to the energy stored in the parasitic capacitor Coss when the power semiconductor device is working.

[0003] The traditional Eoss parameter measurement method uses a linear current correction circuit (LCR) meter combined with a high-voltage power supply to control the high-voltage power supply to charge at different charging voltages, and read the Coss parameter at multiple points, and then calculate the equivalent capacitance Co(er) parameter, and finally use the capacitor energy storage formula: Eoss=(Co(er))2*Vds / 2 to calculate the Eoss parameter. Among them, Eoss represents the energy stored in the parasitic capacitor Coss, Co(er) represents the equivalent capacitance value, and Vds represents the charging voltage value.

[0004] Since it is necessary to measure Coss at multiple points and consider the measurement response time required by the LCR meter, this method has the problems of long measurement time, low accuracy and difficulty in drawing an accurate Eoss / Vds curve.

[0005] It can be seen that how to solve the problem of low efficiency in measuring the Eoss parameter is a technical problem that needs to be solved urgently by people in this field. Summary of the invention

[0006] The purpose of the present application is to provide a method, device and system for measuring the Eoss parameter of a MOS tube, so as to solve the problem of low efficiency in measuring the Eoss parameter by combining an LCR meter with a high voltage power supply.

[0007] In order to solve the above technical problems, the present application provides a method for measuring the Eoss parameter of a MOS tube, comprising:

[0008] Controlling the constant current source to output a target constant current signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0009] Scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2;

[0010] Controlling the constant voltage source to output a target constant voltage signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0011] collecting a target leakage current corresponding to each of the n target drain-source voltages;

[0012] An Eoss parameter corresponding to the MOS tube to be tested is obtained based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents.

[0013] As an optional implementation, in the above-mentioned method for measuring the Eoss parameter of the MOS tube, the step of scanning and acquiring n target drain-source voltages of the MOS tube to be measured based on a preset voltage scanning time interval includes:

[0014] Get the preset voltage scanning time interval;

[0015] Scanning and acquiring n+1 drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval;

[0016] A target drain-source voltage corresponding to a scan time interval is obtained based on any adjacent first drain-source voltage and second drain-source voltage.

[0017] As an optional implementation, in the Eoss parameter measurement method of the MOS tube, the collecting of the target leakage current corresponding to each of the n target drain-source voltages includes:

[0018] Obtaining n target drain-source voltages;

[0019] Controlling a constant voltage source according to any of the target drain-source voltages to apply a corresponding drain-source voltage to the MOS transistor to be tested;

[0020] The target leakage current of the MOS tube to be tested corresponding to each target drain-source voltage is collected.

[0021] As an optional implementation scheme, in the above-mentioned method for measuring the Eoss parameter of the MOS tube, the controlling constant current source to output a target constant current signal to the MOS tube to be measured to charge the parasitic capacitance of the MOS tube to be measured comprises:

[0022] Acquire a target constant current signal that matches the MOS tube to be tested, wherein the target constant current signal is greater than a preset leakage current;

[0023] The constant current source is controlled to output current to the MOS tube to be tested according to the target constant current signal, and the voltage of the constant current source is controlled to be clamped at a preset drain-source voltage value.

[0024] As an optional implementation scheme, in the above-mentioned method for measuring the Eoss parameter of the MOS tube, obtaining the Eoss parameter corresponding to the MOS tube to be measured based on the target constant current signal, the drain-source voltage, and the leakage current includes:

[0025] According to the first formula, the energy change of each scanning time interval is obtained:

[0026] The first formula is: ΔEn=(I-Idss)*U C *(Δt) / 2;

[0027] Wherein, ΔEn is the energy change value of the current scanning time interval; I represents the target constant current signal; U C represents the target drain-source voltage corresponding to the current segment scanning time interval; Idss represents the leakage current corresponding to the current target drain-source voltage; Δt represents the preset voltage scanning time interval;

[0028] Obtaining an Eoss parameter corresponding to each target drain-source voltage according to the energy change and the second formula;

[0029] The second formula is: Eoss n =∑ΔEn;

[0030] Among them, Eoss n represents the Eoss parameter corresponding to the nth target drain-source voltage; ∑ΔEn represents the sum of energy changes corresponding to all scanning time intervals before the current target drain-source voltage.

[0031] As an optional implementation scheme, in the above-mentioned method for measuring the Eoss parameter of the MOS tube, the controlling constant voltage source to output a target constant voltage signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested comprises:

[0032] According to each of the target drain-source voltages, the constant voltage source is controlled to apply a constant voltage to the MOS tube to be tested, and the current is controlled to be clamped at 1 mA.

[0033] As an optional implementation scheme, the Eoss parameter measurement method of the MOS tube further includes:

[0034] An Eoss-Vds graph is generated based on the Eoss parameters corresponding to each target drain-source voltage.

[0035] In order to solve the above technical problems, the present application also provides an Eoss parameter measurement device for a MOS tube, which is characterized by comprising:

[0036] A constant current charging module, used to control the constant current source to output a target constant current signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0037] A target drain-source voltage scanning module, used for scanning and acquiring n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2;

[0038] A constant voltage charging module, used to control the constant voltage source to output a target constant voltage signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0039] A target leakage current acquisition module, used for acquiring a target leakage current corresponding to each of the n target drain-source voltages;

[0040] The Eoss parameter determination module is used to obtain the Eoss parameter corresponding to the MOS tube to be tested based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents.

[0041] In order to solve the above technical problems, the present application also provides an Eoss parameter measurement device for a MOS tube, comprising: a host computer, a high-voltage source meter, and a power semiconductor tester loaded with a power chip to be tested; the power chip to be tested includes at least one MOS tube to be tested; the host computer is connected to the high-voltage source meter, and the high-voltage source meter is connected to the MOS tube to be tested through the power semiconductor tester;

[0042] The host computer controls the high-voltage source meter as a constant current source to output a target constant current signal to the MOS tube to be tested, charges the parasitic capacitance of the MOS tube to be tested, and controls the high-voltage source meter to scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2;

[0043] The host computer controls the high-voltage source meter as a constant voltage source to output a target constant voltage signal to the MOS tube to be tested, charges the parasitic capacitance of the MOS tube to be tested, and collects the target leakage current corresponding to each of the n target drain-source voltages; and obtains the Eoss parameter corresponding to the MOS tube to be tested based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents.

[0044] As an optional implementation scheme, in the Eoss parameter measurement system of the MOS tube, the host computer collects the leakage current of the MOS tube to be measured corresponding to each of the target drain-source voltages through the high-voltage source meter.

[0045] The Eoss parameter measurement method of the MOS tube provided in the present application controls the constant current source to output a target constant current signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested; obtains n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2; controls the constant voltage source to output a target constant voltage signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested; collects the target leakage current corresponding to each of the n target drain-source voltages; obtains the Eoss parameter corresponding to the MOS tube to be tested based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents. The present application charges the parasitic capacitance of the MOS tube in constant current and constant voltage modes respectively, and simultaneously monitors the target drain-source voltage and target leakage current between the drain and the source to calculate the Eoss parameter. By controlling the constant current source charging, the need to frequently adjust the setting parameters and affect the test efficiency is avoided. By regularly collecting voltage data, the collection accuracy and the number of sampling points are improved, the measurement accuracy of the Eoss parameter is improved, and the automatic and rapid measurement of the Eoss parameter is achieved. The LCR meter is no longer needed, which reduces human operation errors and speeds up the test.

[0046] In addition, the present application also provides an Eoss parameter measurement device and system for a MOS tube, which correspond to the Eoss parameter measurement method for the above-mentioned MOS tube, and have the same effect as above. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0048] Figure 1 A flow chart of a method for measuring the Eoss parameter of a MOS tube provided in an embodiment of the present application;

[0049] Figure 2 A schematic diagram of an Eoss-Vds curve provided in an embodiment of the present application;

[0050] Figure 3 A schematic diagram of an Eoss parameter measurement device for a MOS tube provided in an embodiment of the present application;

[0051] Figure 4 A schematic diagram of an Eoss parameter measurement system for a MOS tube provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0053] The core of this application is to provide a method, device and system for measuring the Eoss parameters of a MOS tube.

[0054] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0055] When the power device is working, the drain-source voltage Vds of the Metal-Oxide-Semiconductor Field-Effect Transistor (MOS tube) changes between 0 and the power rail voltage. The circuit needs to continuously charge and discharge the MOS tube to consume energy. After charging, the MOS tube obtains the energy Eoss stored in the parasitic capacitor Coss. The more commonly used Eoss parameter test scheme is usually based on the Coss parameter and the drain-source voltage Vds to calculate the Eoss parameter. The Coss parameter is a parasitic parameter of the power semiconductor device. It changes with the operating voltage of the device and is not a constant parameter. Therefore, when measuring the conventional Eoss parameter, it is necessary to obtain an equivalent capacitance Co(er) and then calculate Eoss based on the capacitor energy storage formula.

[0056] The above conventional measurement method requires a high voltage source, LCR and a host computer; the host computer controls the high voltage source to generate a stable voltage source, which is applied to the device under test, and the LCR is connected to the device under test through a coupling circuit. In the specific test, the host computer first controls the voltage source to generate a constant voltage source. After the voltage stabilizes, the LCR measures the parasitic capacitance Coss value of the device under this voltage condition, and the host computer reads the capacitance value Coss measured by the LCR; in this way, the voltage is continuously changed until the voltage value of the test condition is reached. At the same time, the LCR meter also measures multiple Coss values ​​as the test voltage changes, and finally calculates the equivalent capacitance Co(er), and then calculates the Eoss parameter value;

[0057] During this test, the voltage needs to be stabilized after the change, and the LCR measurement time is long, resulting in the entire process measuring time taking seconds, which has a great impact on the test efficiency of the production line. The entire measurement process takes a long time, affecting production efficiency; the measurement accuracy is not high, because different points have different Coss, which has a great impact on the measurement accuracy; because the points are limited, it is difficult to draw an accurate Eoss / Vds curve.

[0058] To solve the above problems, the present application provides a method for measuring the Eoss parameter of a MOS tube. Figure 1 As shown, including:

[0059] S11: Control the constant current source to output a target constant current signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0060] S12: Scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2;

[0061] S13: Control the constant voltage source to output a target constant voltage signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0062] S14: collecting a target leakage current corresponding to each of the n target drain-source voltages;

[0063] S15: Obtaining an Eoss parameter corresponding to the MOS tube to be tested based on the target constant current signal, n target drain-source voltages, and n target leakage currents.

[0064] It should be noted that since the Coss parameter changes with the voltage Vds, Coss is larger at low voltage. When a smaller constant current is used for charging, the capacitance value is larger and the Vds caused by constant current charging increases slowly. In a fast and small interval time t, Coss can be considered to be a constant value, and the energy storage of the capacitor can be calculated using the energy calculation formula for a constant capacitance value.

[0065] Because Coss changes, when using constant current charging, the energy provided by the high-voltage source is stored and accumulated by the parasitic capacitor, causing the Vds voltage to increase. The energy stored in the capacitor is Eoss.

[0066] Charging with constant current I, at any sampling point m, the energy in the interval from sampling point m+1 is:

[0067] At time t1, the voltage is U1, and the energy value of sampling point m is: E1=I*t1*U1 / 2;

[0068] At time t2, the voltage is U2, and the energy value of sampling point m+1 is: E2=I*t2*U2 / 2;

[0069] Since the sampling interval is short enough, it can be regarded as a constant pressure U during this period. C For charging, for ease of calculation, the calculated voltage is taken as a linear value U between voltages U1 and U2. C =(U1+U2) / 2;

[0070] Therefore, the energy increase from time t1 to time t2 is ΔE: ΔE=I*U C *(Δt) / 2;

[0071] Because the power device has leakage current when it is externally biased, the current parameter used for calculation needs to be subtracted from the leakage current Idss at this voltage point, Ic=I-Idss;

[0072] So the actual increase in energy from t1 to t2 is ΔE = Ic*U C *(Δt) / 2;

[0073] The energy increase between each two adjacent sampling points is calculated one by one by charging at an approximately constant voltage, and then the gradually changing energy stored in the capacitor can be calculated by accumulation.

[0074] Therefore, step S11 controls the constant current source to output a target constant current signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested. The constant current source refers to a device that can provide a stable current output, which can be specifically an electronic load or a dedicated constant current power supply. In this step, the parasitic capacitance of the MOS tube is charged by the constant current source to simulate the capacitance charging behavior of the MOS tube under actual working conditions.

[0075] It should be noted that the "target constant current signal" refers to a constant current value set according to the test requirements, which can be specifically a current of microampere or milliampere level. In this field, it is common to use a digital power supply or an electronic load as a constant current source to achieve precise current control.

[0076] Specifically, charging stops when the voltage reaches a preset value.

[0077] Step S12 obtains n target drain-source voltages of the MOS tube to be tested based on the preset voltage scanning time interval, where n≥2. The "preset voltage scanning time interval" refers to the time interval used to control the voltage acquisition frequency during the charging process of the MOS tube, which can be specifically 1ms, 0.1ms or any time unit set according to the test requirements; in this step, the timed acquisition of voltage can be achieved by using a timer or a computer program. The selection of the time interval depends on the measurement accuracy requirements and the charging speed of the MOS tube. At least two or more voltage values ​​are collected during the charging process; in this step, the continuous acquisition of voltage data is achieved through automated testing equipment. The target drain-source voltage refers to the approximate constant voltage value between each two adjacent acquisition points, and the target drain-source voltage can be determined by the mean, median, etc. of the voltages at two adjacent points.

[0078] Step S13 controls the constant voltage source to output a target constant voltage signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested. The "target constant voltage signal" refers to a constant voltage value set according to the test requirements, which can be any value within the rated voltage range of the MOS tube. The constant voltage source is used to charge the MOS tube at a constant voltage to maintain voltage stability and perform subsequent leakage current measurement.

[0079] Step S14 collects the target leakage current corresponding to each of the n target drain-source voltages. The "target leakage current" refers to the leakage current through the MOS tube under constant voltage conditions, which can be specifically the leakage current value read under each constant voltage condition. In this step, the leakage current is accurately collected by a current measuring device. The leakage current can be measured by a current measuring device (such as a digital multimeter or a dedicated semiconductor parameter analyzer).

[0080] Specifically, based on the target constant current signal, n target drain-source voltages, and n target leakage currents, the Eoss parameter corresponding to the MOS tube to be tested is obtained, including:

[0081] According to the first formula, the energy change of each scanning time interval is obtained:

[0082] The first formula is: ΔEn=(I-Idss)*U C *(Δt) / 2;

[0083] Among them, ΔEn is the energy change value of the current scanning time interval; I represents the target constant current signal; U C represents the target drain-source voltage corresponding to the current segment scanning time interval; Idss represents the target leakage current corresponding to the current target drain-source voltage; Δt represents the preset voltage scanning time interval;

[0084] According to the energy change and the second formula, the Eoss parameter corresponding to each target drain-source voltage is obtained;

[0085] The second formula is: Eoss n+1 =∑ΔEn;

[0086] Among them, Eoss n+1 represents the Eoss parameter corresponding to the n+1th target drain-source voltage; ∑ΔEn represents the sum of energy changes corresponding to the first n scanning time intervals.

[0087] The energy changes of adjacent sampling points are obtained according to the first formula, and the corresponding Eoss parameters are further accumulated according to the energy changes of each time interval. Specifically, the target drain-source voltage and the corresponding target leakage current of 100 time intervals are collected, and 100 ΔEn are obtained according to the first formula. The energy of the first sampling point is set to 0, and the first 10 ΔEn are accumulated to obtain the Eoss parameter of the 11th point, the first 50 ΔEn are accumulated to obtain the Eoss parameter of the 51st point, and 100 ΔEn are accumulated to obtain the Eoss parameter of the 101st point. Multiple Eoss parameters can be used to draw the corresponding Eoss-Vds curve.

[0088] Through the Eoss parameter measurement method of the MOS tube provided in this embodiment, the constant current source is controlled to output a target constant current signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested; based on the preset voltage scanning time interval, the n target drain-source voltages of the MOS tube to be tested are scanned and obtained, where n≥2; the constant voltage source is controlled to output a target constant voltage signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested; the target leakage current corresponding to each of the n target drain-source voltages is collected; based on the target constant current signal, the n target drain-source voltages, and the n target leakage current, the Eoss parameter corresponding to the MOS tube to be tested is obtained. The present application charges the parasitic capacitance of the MOS tube in constant current and constant voltage modes respectively, and simultaneously monitors the target drain-source voltage and target leakage current between the drain and the source to calculate the Eoss parameter. By controlling the constant current source charging, the need to frequently adjust the setting parameters and affect the test efficiency is avoided. By regularly collecting voltage data, the collection accuracy and the number of sampling points are improved, the measurement accuracy of the Eoss parameter is improved, and the automatic and rapid measurement of the Eoss parameter is achieved. The LCR meter is no longer needed, which reduces human operation errors and speeds up the test.

[0089] According to the above embodiment, further in a specific solution, the Eoss parameter measurement method of the MOS tube, based on a preset voltage scanning time interval, scans and obtains n target drain-source voltages of the MOS tube to be tested, including:

[0090] Get the preset voltage scanning time interval;

[0091] Scan and obtain n+1 drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval;

[0092] A target drain-source voltage corresponding to a scan time interval is obtained based on any adjacent first drain-source voltage and second drain-source voltage.

[0093] The preset voltage scanning time interval refers to the time interval used to control the voltage acquisition frequency during the MOS tube charging process, which can be specifically 1ms, 10ms or any time unit set according to the test requirements; in order to ensure that the drain-source voltage changes of the MOS tube can be continuously and evenly monitored during the charging process, so as to accurately capture the dynamic behavior of the voltage, the preset voltage scanning time interval cannot be too large or too small. The timed acquisition of the drain-source voltage can be achieved by using a timer or a computer program.

[0094] During the charging process, the drain-source voltage value is read from the MOS tube at every preset time interval. After obtaining n+1 drain-source voltages, the target drain-source voltage in each preset time interval is determined by processing these data, for example, by calculating the average or median of adjacent voltage values ​​to reduce random errors.

[0095] According to the above embodiment, in order to accurately measure the leakage current of the MOS tube at different voltages, a specific solution is further provided, in which the Eoss parameter measurement method of the above MOS tube collects the target leakage current corresponding to each target drain-source voltage of n target drain-source voltages, including:

[0096] Obtain n target drain-source voltages;

[0097] According to any target drain-source voltage, a constant voltage source is controlled to apply a corresponding drain-source voltage to the MOS tube to be tested;

[0098] The target leakage current of the MOS tube to be tested corresponding to each target drain-source voltage is collected.

[0099] Acquiring multiple target drain-source voltages refers to obtaining drain-source voltage values ​​at n different stages through constant current charging and voltage scanning in the aforementioned steps.

[0100] Use a constant voltage source device to apply a corresponding constant voltage to the MOS tube according to each measured drain-source voltage value to simulate the leakage current under different working conditions. Apply a constant drain-source voltage to the MOS tube through a constant voltage source to ensure accurate leakage current measurement at each voltage point.

[0101] Collecting the target leakage current of the MOS tube to be tested corresponding to each target drain-source voltage refers to measuring and recording the leakage current through the MOS tube using a current measuring device under constant voltage conditions. Specifically, the leakage current value can be read under each constant voltage condition using a current measuring device; in this step, accurate collection of the leakage current is achieved through the current measuring device.

[0102] This embodiment can ensure that the leakage current data measured at each voltage point is more accurate by precisely controlling the constant voltage source to apply a constant charging voltage corresponding to each target drain-source voltage, thereby improving the accuracy of Eoss parameter calculation.

[0103] According to the above embodiment, in order to ensure that the parasitic capacitance of the MOS tube can be safely and effectively charged during the measurement process, and control the charging process to be performed within a safe voltage range, in a specific solution, the Eoss parameter measurement method of the above MOS tube controls the constant current source to output a target constant current signal to the MOS tube to be measured to charge the parasitic capacitance of the MOS tube to be measured, including:

[0104] Obtaining a target constant current signal that matches the MOS tube to be tested, wherein the target constant current signal is greater than a preset leakage current;

[0105] The constant current source is controlled to output current to the MOS tube to be tested according to the target constant current signal, and the voltage of the constant current source is controlled to be clamped at a preset drain-source voltage value.

[0106] Obtaining a target constant current signal that matches the MOS tube to be tested refers to determining a current value that is suitable for a specific MOS tube model and specification. This value can be provided by the data sheet of the MOS tube, specifically a current value at the microampere level. In this step, the target constant current signal is determined by consulting the technical specification sheet of the MOS tube or using empirical values.

[0107] The target constant current signal is greater than the maximum leakage current of the MOS tube in the off state to ensure that sufficient current can be provided to charge the parasitic capacitor during the measurement process, while avoiding measurement errors caused by excessive leakage current.

[0108] Controlling the constant current source to output current to the MOS tube to be tested according to the target constant current signal refers to using a constant current source device to provide a constant current to the MOS tube according to a preset current value; in this step, constant current charging of the MOS tube is achieved by adjusting the output setting of the constant current source.

[0109] Controlling the voltage clamp of the constant current source to a preset drain-source voltage value refers to setting the voltage clamp function of the constant current source to ensure that the drain-source voltage of the MOS tube does not exceed a safe value during the charging process; in this step, the drain-source voltage is controlled by the voltage protection function of the constant current source.

[0110] This embodiment can effectively prevent the MOS tube from being damaged due to excessive voltage by controlling the voltage clamp of the constant current source to be at a preset drain-source voltage value, thereby improving the safety of the test process. Ensuring that the target constant current signal is greater than the preset leakage current can provide sufficient current to accurately charge the parasitic capacitance of the MOS tube, thereby making subsequent voltage and current measurements more accurate.

[0111] According to the above embodiment, in a specific solution, the Eoss parameter measurement method of the above MOS tube controls the constant voltage source to output a target constant voltage signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested, including:

[0112] According to each target drain-source voltage, the constant voltage source is controlled to apply a constant voltage to the MOS tube to be tested, and the current is controlled to be clamped at 1mA.

[0113] The target drain-source voltage is used to control the voltage applied by the constant voltage source in this step. A constant voltage source device is used to apply a constant voltage to the MOS tube according to the above target drain-source voltage. And controlling the current clamp at 1mA means setting the current clamp to 1mA while applying the constant voltage to ensure that the current passing through the MOS tube is limited to a safe range when measuring the leakage current; in this step, the current is controlled by the current clamp function of the constant voltage source.

[0114] This embodiment controls the constant voltage source to apply constant voltage, ensuring that the drain-source voltage of the MOS tube remains stable when measuring the leakage current, thereby improving the stability of the measurement. The current is clamped at 1mA to prevent thermal damage or other damage to the MOS tube due to excessive current, ensuring the safety of the test process.

[0115] According to the above embodiment, in a specific solution, the Eoss parameter measurement method of the MOS tube further includes:

[0116] An Eoss-Vds graph is generated based on the Eoss parameters corresponding to each target drain-source voltage.

[0117] The Eoss parameter values ​​are calculated by the leakage current under different target drain-source voltages. These values ​​reflect the energy consumption characteristics of the MOS tube under different voltages; in this step, the Eoss parameter values ​​corresponding to each target drain-source voltage point are plotted into a graph using a software tool, with the horizontal axis representing the target drain-source voltage (Vds) and the vertical axis representing the Eoss parameter value. Figure 2 A schematic diagram of an Eoss-Vds curve provided in an embodiment of the present application, such as Figure 2 As shown, the Eoss-Vds curve graphs the Eoss parameter and the corresponding drain-source voltage value to visually display the relationship between them. In this step, the graphical display can be used to more intuitively understand the performance of the MOS tube, which helps to quickly identify abnormal points and trend changes in the performance of the MOS tube and assist in fault diagnosis.

[0118] Based on the perspective of functional modules, the present application also provides an Eoss parameter measurement device for a MOS tube, such as Figure 3 As shown, including:

[0119] The constant current charging module 11 is used to control the constant current source to output a target constant current signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0120] A target drain-source voltage scanning module 12 is used to scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2;

[0121] The constant voltage charging module 13 is used to control the constant voltage source to output a target constant voltage signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested;

[0122] A target leakage current acquisition module 14, used to acquire a target leakage current corresponding to each target drain-source voltage among the n target drain-source voltages;

[0123] The Eoss parameter determination module 15 is used to obtain the Eoss parameter corresponding to the MOS tube to be tested based on the target constant current signal, n target drain-source voltages, and n target leakage currents.

[0124] Since the embodiments of the apparatus part correspond to the embodiments of the method part, please refer to the description of the embodiments of the method part for the embodiments of the apparatus part, which will not be repeated here.

[0125] In addition, the present application also provides a MOS tube Eoss parameter measurement system, such as Figure 4 As shown, it includes: a host computer 21, a high-voltage source meter 22, and a power semiconductor tester 24 loaded with a power chip to be tested; the power chip to be tested includes at least one MOS tube to be tested 23; the host computer 21 is connected to the high-voltage source meter 22, and the high-voltage source meter 22 is connected to the MOS tube to be tested 23 through the power semiconductor tester 24;

[0126] The host computer 21 controls the high-voltage source meter 22 as a constant current source to output a target constant current signal to the MOS tube 23 to be tested, so as to charge the parasitic capacitance of the MOS tube 23 to be tested, and controls the high-voltage source meter 22 to scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2;

[0127] The host computer 21 controls the high-voltage source meter 22 as a constant voltage source to output a target constant voltage signal to the MOS tube 23 to be tested, charges the parasitic capacitance of the MOS tube 23 to be tested, and collects the target leakage current corresponding to each of the n target drain-source voltages; and obtains the Eoss parameter corresponding to the MOS tube 23 to be tested based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents.

[0128] The host computer 21 (computer) is responsible for issuing instructions and processing data. It controls the working mode of the high-voltage source meter 22, collects and processes data obtained from the high-voltage source meter and the MOS tube to be tested, calculates the Eoss parameter, and outputs the result. It is connected to the high-voltage source meter through a communication interface, such as Universal Serial Bus (USB), General-Purpose Interface Bus (GPIB), Ethernet, etc., to realize the transmission of data and control signals.

[0129] The high-voltage source meter is directly connected to the MOS tube to be tested, provides a constant current source or a constant voltage source according to the instructions of the host computer, and measures the drain-source voltage and leakage current.

[0130] The MOS tube to be tested is the measurement object, and its Eoss parameter needs to be measured by the above system. During the measurement process, as the current receiving end and voltage generating end, its drain-source voltage and leakage current are measured and used to calculate the Eoss parameter. Connected to the high-voltage source meter, it receives a constant current and provides voltage and current measurement values.

[0131] The host computer controls the high-voltage source meter as a constant current source, outputs a target constant current signal to the MOS tube to be tested, and charges the parasitic capacitance of the MOS tube. The host computer controls the high-voltage source meter to scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2. The host computer controls the high-voltage source meter as a constant voltage source, outputs a target constant voltage signal to the MOS tube to be tested, and collects the target leakage current corresponding to each target drain-source voltage. The host computer calculates the Eoss parameter of the MOS tube to be tested based on the target constant current signal, n target drain-source voltages, and n target leakage currents.

[0132] The system consists of two main modules: the host computer and the high-voltage source meter. The host computer is responsible for control and data processing, and the high-voltage source meter is responsible for direct interaction with the MOS tube to be tested. The host computer not only controls the measurement process, but is also responsible for data collection and processing, including the measured values ​​of voltage and current, as well as the final Eoss parameter calculation.

[0133] When the drain-source voltage reaches the preset voltage value, the host computer can control the high-voltage source meter to stop outputting current in real time. This real-time feedback mechanism ensures the safety of the measurement process. The high-voltage source meter can accurately obtain the drain-source voltage and the corresponding leakage current according to the preset voltage scanning time interval.

[0134] Furthermore, in the Eoss parameter measurement system of the MOS tube, the host computer collects the leakage current of the MOS tube to be measured corresponding to each target drain-source voltage through a high-voltage source meter.

[0135] In addition to providing constant current and constant voltage signals, the high-voltage source meter also has the function of measuring leakage current. It is directly connected to the MOS tube to be tested to apply voltage and measure the leakage current through the MOS tube. The host computer receives the leakage current data and calculates the Eoss parameter in combination with the target constant current signal and the target drain-source voltage.

[0136] The host computer may also perform further analysis of the data, such as drawing an Eoss-Vds curve and determining whether the MOS tube is qualified.

[0137] The entire measurement process is automatically controlled by the host computer, which reduces human operation errors and improves measurement efficiency. The host computer can receive data from the high-voltage source meter in real time and adjust the control strategy as needed to ensure the stability and safety of the measurement process.

[0138] The Eoss parameter measurement method, device and system of the MOS tube provided by the present application are introduced in detail above. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can refer to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can refer to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

[0139] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A method for measuring the Eoss parameter of a MOS tube, characterized in that: include: Controlling the constant current source to output a target constant current signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested; Scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2; Controlling the constant voltage source to output a target constant voltage signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested; collecting a target leakage current corresponding to each of the n target drain-source voltages; An Eoss parameter corresponding to the MOS tube to be tested is obtained based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents.

2. The method for measuring the Eoss parameter of a MOS tube according to claim 1, characterized in that: The step of scanning and acquiring n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval includes: Get the preset voltage scanning time interval; Scanning and acquiring n+1 drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval; A target drain-source voltage corresponding to a scan time interval is obtained based on any adjacent first drain-source voltage and second drain-source voltage.

3. The method for measuring the Eoss parameter of a MOS tube according to claim 2, characterized in that: The collecting of the target leakage current corresponding to each of the n target drain-source voltages comprises: Obtaining n target drain-source voltages; Controlling a constant voltage source according to any of the target drain-source voltages to apply a corresponding drain-source voltage to the MOS transistor to be tested; The target leakage current of the MOS tube to be tested corresponding to each target drain-source voltage is collected.

4. The method for measuring the Eoss parameter of a MOS tube according to claim 3, characterized in that: The controlling constant current source to output a target constant current signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested comprises: Acquire a target constant current signal that matches the MOS tube to be tested, wherein the target constant current signal is greater than a preset leakage current; The constant current source is controlled to output current to the MOS tube to be tested according to the target constant current signal, and the voltage of the constant current source is controlled to be clamped at a preset drain-source voltage value.

5. The method for measuring the Eoss parameter of a MOS tube according to claim 1, characterized in that: The obtaining the Eoss parameter corresponding to the MOS tube to be tested based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents includes: According to the first formula, the energy change of each scanning time interval is obtained: The first formula is: ΔEn=(I-Idss)*U C *(Δt) / 2; Wherein, ΔEn is the energy change value of the current scanning time interval; I represents the target constant current signal; U C represents the target drain-source voltage corresponding to the current segment scanning time interval; Idss represents the target leakage current corresponding to the current target drain-source voltage; Δt represents the preset voltage scanning time interval; Obtaining an Eoss parameter corresponding to each target drain-source voltage according to the energy change and the second formula; The second formula is: Eoss n+1 =∑ΔEn; Among them, Eoss n+1 represents the Eoss parameter corresponding to the n+1th target drain-source voltage; ∑ΔEn represents the sum of energy changes corresponding to the first n scanning time intervals.

6. The method for measuring the Eoss parameter of a MOS tube according to claim 3, characterized in that: The controlling constant voltage source to output a target constant voltage signal to the MOS tube to be tested to charge the parasitic capacitance of the MOS tube to be tested comprises: According to each of the target drain-source voltages, the constant voltage source is controlled to apply a constant voltage to the MOS tube to be tested, and the current is controlled to be clamped at 1 mA.

7. The method for measuring the Eoss parameter of a MOS tube according to claim 5, characterized in that: The method further comprises: An Eoss-Vds graph is generated based on the Eoss parameters corresponding to each target drain-source voltage.

8. A device for measuring the Eoss parameter of a MOS tube, characterized in that: include: A constant current charging module, used to control the constant current source to output a target constant current signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested; A target drain-source voltage scanning module, used for scanning and acquiring n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2; A constant voltage charging module, used to control the constant voltage source to output a target constant voltage signal to the MOS tube to be tested, so as to charge the parasitic capacitance of the MOS tube to be tested; A target leakage current acquisition module, used for acquiring a target leakage current corresponding to each of the n target drain-source voltages; The Eoss parameter determination module is used to obtain the Eoss parameter corresponding to the MOS tube to be tested based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents.

9. A MOS tube Eoss parameter measurement system, characterized in that: include: A host computer, a high-voltage source meter, and a power semiconductor tester loaded with a power chip to be tested; the power chip to be tested includes at least one MOS tube to be tested; the host computer is connected to the high-voltage source meter, and the high-voltage source meter is connected to the MOS tube to be tested through the power semiconductor tester; The host computer controls the high-voltage source meter as a constant current source to output a target constant current signal to the MOS tube to be tested, charges the parasitic capacitance of the MOS tube to be tested, and controls the high-voltage source meter to scan and obtain n target drain-source voltages of the MOS tube to be tested based on a preset voltage scanning time interval, where n≥2; The host computer controls the high-voltage source meter as a constant voltage source to output a target constant voltage signal to the MOS tube to be tested, charges the parasitic capacitance of the MOS tube to be tested, and collects a target leakage current corresponding to each of the n target drain-source voltages; And based on the target constant current signal, the n target drain-source voltages, and the n target leakage currents, an Eoss parameter corresponding to the MOS tube to be tested is obtained.

10. The Eoss parameter measurement system of the MOS tube according to claim 9, characterized in that: The host computer collects the leakage current of the MOS tube to be tested corresponding to each of the target drain-source voltages through the high-voltage source meter.

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