Modularized test method for high and low temperature dynamic parameters of power semiconductor device

Abstract

The invention discloses a power semiconductor device high and low temperature dynamic parameter modularization test method comprising the following steps: selecting a driving resistor, an output clamping circuit and a modularization test clamp, building an input voltage peak protection circuit, and installing the input voltage peak protection circuit in a driving circuit of the test clamp; installing a test fixture, and enabling the interface of the test fixture to be reliably contacted with the interface of the test equipment; a to-be-tested device sample is installed on the test fixture, and device pins are in reliable contact with probes on the test fixture; placing the test fixture provided with the to-be-tested device sample in a high and low temperature test system, performing temperature control on the high and low temperature test system to enable the temperature of the sample to be stable, performing sample debugging from low voltage to high voltage and from low current to high current, and ensuring that the voltage and current waveforms of the device are smooth; and executing a dynamic performance index parameter test of the device to obtain test data. According to the invention, high-speed and high-precision dynamic parameter testing of the power semiconductor device and dynamic performance testing of the device at high and low temperatures can be realized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of semiconductor device testing, and particularly relates to a high-low temperature dynamic parameter modular testing method for power semiconductor devices. BACKGROUND

[0002] Power semiconductor devices such as SiC MOSFET and Si IGBT (Insulate-Gate Bipolar Transistor) have become the core devices in the fields of new energy vehicle high-voltage platforms, photovoltaic inverters and rail transit, due to their high frequency, high voltage resistance and high temperature resistance. These scenarios have strict requirements for system efficiency and reliability, for example, the power switching of an electric vehicle inverter needs to be completed within milliseconds, and a photovoltaic system needs to operate stably in a high-temperature desert environment. International standards such as ECPE AQG-324 and IEC 60747 clearly require testing of dynamic parameters such as switching loss and delay time, and promote the upgrading of testing technology from static analysis to high-frequency dynamic characteristics.

[0003] Double-pulse testing is a traditional experimental method for evaluating the dynamic characteristics of power semiconductor devices, and can be applied to the dynamic parameter testing of power semiconductor single tubes and modules. This testing method generates drain voltage / current pulse waveforms by applying a double-pulse driving signal, which is used to measure key dynamic parameters such as switching time of power SiC MOSFET, IGBT and other devices. Although the existing double-pulse testing can partially evaluate dynamic characteristics, it has the following significant defects: it faces the challenge of compatibility with multiple packaging forms, the traditional fixture needs special customization, the lack of standardized interface design makes the tool switching efficiency low, and it cannot meet the dual requirements of mechanical stability and electrical consistency in high-frequency testing scenarios; it relies heavily on welding fixation process, which causes deformation or damage to the oxide layer of the device pins due to thermal stress, and the electrical performance deteriorates after secondary disassembly, non-contact testing solutions can avoid physical damage, but they have the problem of unstable contact impedance, and lack of reversible fastening mechanism, making it difficult to maintain contact reliability in a wide temperature range; it can only measure device parameters at room temperature, and it is difficult to consider the accuracy of performance indicators of devices at high and low temperatures; it is easy to cause device damage and fixture failure due to excessive instantaneous peak voltage. SUMMARY

[0004] The purpose of the present application is to provide a high-low temperature dynamic parameter modular testing method for power semiconductor devices, which can realize high-speed and high-precision dynamic parameter testing of power semiconductor devices and testing of dynamic performance of devices at high and low temperatures.

[0005] In order to achieve the above-mentioned purpose, one aspect of the present application provides a high-low temperature dynamic parameter modular testing method for power semiconductor devices, comprising: Step S1, according to the device parameters of the device to be tested, the driving resistance and the output clamping circuit are selected, according to the packaging structure and the device type of the device to be tested, the modular test fixture is selected, according to the device parameters and the test type, the input voltage peak protection circuit is built, and is installed in the driving circuit of the test fixture; Step S2, the test fixture is installed, and the interface of the test fixture is reliably and closely contacted with the interface of the test equipment; Step S3, the device sample to be tested is installed on the test fixture, and the device pin is reliably and closely contacted with the probe on the test fixture; Step S4, the test fixture with the installed device sample to be tested is placed in the high-low temperature test system, the high-low temperature test system is controlled in temperature, and the sample temperature is kept stable for a period of time, then the sample debugging is performed, from low voltage to high voltage, from low current to high current, and the smooth device voltage and current waveform is ensured; Step S5, the dynamic performance index parameter test of the device is performed, and the test data is obtained.

[0006] According to the power semiconductor device high-low temperature dynamic parameter modular test method of the above aspect of the present application, the high-speed high-precision dynamic parameter test of the SiC / IGBT and other power semiconductor devices and the test of the dynamic performance of the device under high and low temperatures can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0007] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings used in the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor: Figure 1 is a flow chart of the power semiconductor device high-low temperature dynamic parameter modular test method of an embodiment of the present application; Figure 2 is a schematic diagram of the input voltage peak protection circuit of an embodiment of the present application; Figure 3 is a structural schematic diagram of the high-low temperature dynamic parameter modular test system of an embodiment of the present application. DETAILED DESCRIPTION

[0008] In order to make the purpose, technical solutions and advantages of the present application more clear, the technical solutions of the present application will be described clearly and completely in the following with reference to the drawings. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0009] One embodiment of the present invention provides a modular testing method for dynamic parameters of power semiconductor devices at high and low temperatures, which can realize the turn-on delay time of power semiconductor devices such as SiC / IGBT under high and low temperature conditions. Ascent time Shutdown delay time descent time Activate energy Shutting off energy Total gate charge Short-circuit current Testing of dynamic parameters. In this embodiment, the dynamic parameter testing of a SiC device is used as an example to illustrate the modular testing method for high and low temperature dynamic parameters of power semiconductor devices according to this invention.

[0010] Some parameters of this SiC device are shown in Table 1 below: Table 1. Partial parameters of SiC devices

[0011] like Figure 1 As shown, the modular testing method for high and low temperature dynamic parameters of power semiconductor devices according to an embodiment of the present invention includes the following steps S1 to S5.

[0012] Step S1, Preparation before testing: The function of the drive resistor is to control the current to drive the device switching. It is calculated and selected based on the gate resistance of the device under test (DUT), and its value is fine-tuned to ensure a smooth drive current is supplied to the device gate after passing through the drive resistor. The magnitude of the current affects the switching speed. For example, the drive resistor for this SiC device is selected based on the gate resistance. =2Ω.

[0013] The output clamping circuit is located between the collector and emitter terminals of the device and consists of multiple TVS diodes (transient voltage suppressor diodes). Its function is to suppress output voltage overshoot and protect the device. The selection criterion is to control the number of TVS diodes in series based on the device's maximum rated voltage. Taking a 75V TVS diode as an example, the maximum rated drain-source voltage of this SiC device is... =750V, then 10 need to be connected in series.

[0014] The test fixture is a tool for fixing the device to be tested and leading out the test pins thereof and connecting with the test equipment, and the fixture is mainly selected according to the packaging structure of the device to be tested. Since different test samples require different test fixtures, the replaceable test fixture is adopted to facilitate the test of different samples, and different fixtures are designed according to the difference of the test samples. The test fixture is selected according to the interface probe position (depending on the packaging) and the device type (the fixture circuit corresponding to different device types will be different). Consistent interfaces are adopted between different fixtures and the test equipment, and these interfaces are used for the electrical parameter connection between the equipment and the fixture and the device to be tested. If the test sample changes, the corresponding test fixture can be replaced.

[0015] The voltage spike protection circuit is a kind of filter circuit, which aims to protect the device to be tested and other elements in the detection circuit. The input voltage fluctuation can be inhibited to make it more stable, thereby preventing the noise spike in the input signal from causing the output signal abnormal, ensuring the output stability of the overall circuit, and avoiding damage caused by the instantaneous high voltage spike due to the switching action. The circuit includes a capacitor, a resistor and a diode, as shown in Figure 2 , wherein the resistor and the diode are connected in series and the capacitor is connected in parallel with the resistor and the diode.

[0016] Capacitor: The parallel capacitor has the ability to store and release energy. When a voltage spike occurs, the capacitor will be charged rapidly to absorb the spike energy.

[0017] Resistance: When the capacitor is charged, the resistance limits the size of the charging current to prevent damage to the circuit caused by excessive current. When the capacitor is discharged, the resistance consumes the energy stored in the capacitor, causing the capacitor voltage to gradually decrease, avoiding the capacitor maintaining a high voltage state for a long time.

[0018] Diode: When the voltage spike exceeds the conduction voltage of the diode (usually 0.7V), the diode will be turned on to provide a low impedance discharge path for the spike voltage. At this time, the spike voltage will form a loop through the diode and the RC circuit, which will be effectively absorbed and dissipated.

[0019] Parameter selection: The diode selected is a diode with a reverse recovery time of 30ns or less. The selection of the capacitor and the resistor mainly depends on the RC time constant , which determines the charging and discharging speed of the capacitor. Reasonable selection of R and C values can make the circuit respond quickly when a spike voltage occurs and quickly recover to normal state after the spike. R is selected as the value of the gate resistor, i.e. the value in the table , which is 2Ω in this example. C is adjusted according to the frequency of the voltage pulse used in the test, and the filter center frequency range is between the pulse frequency and the spike frequency.

[0020] Step S2, test equipment and fixture preparation: perform self-checking through the automated test equipment console to ensure that each test module inside the test equipment is normal. After self-checking is completed, install the modular fixture tooling so that the interface of the fixture reliably and tightly contacts the interface on the test equipment, and turn on the high-voltage protection switch. The modular design of the fixture tooling can be compatible with different packaging types, and through replaceable probe groups, the rapid switching test of IGBT and SiC devices can be realized, and the test efficiency is improved.

[0021] Step S3, sample installation and connection detection: install the SiC device sample to be tested on the sample table of the fixture, and make the pins of the device reliably and tightly contact the probes on the fixture through crimping fixation or the like. Enter the test system to run the Kelvin test program, which is used to detect whether the device sample and the system connection are good.

[0022] Step S4, temperature setting and sample debugging: place the test fixture with the installed device sample to be tested in the high-low temperature test system to obtain a high-low temperature dynamic parameter modular test system as shown in Figure 3 First, control the temperature conditions of the high-low temperature test system, such as room temperature or high temperature, and maintain the temperature for a period of time to make the sample temperature stable. Then, perform sample debugging from low voltage to high voltage, and from low current to high current to ensure that the device voltage and current waveforms are smooth to adapt to production testing. If the device test waveform fluctuates too much, the device parameters of the clamping circuit can be adjusted for fine tuning.

[0023] The test fixture interface is used to transmit the power and signals from the test equipment to the device to be tested, and quickly read the test result parameters of the device to be tested. Place the sample and the fixture in a high-low temperature generating device, heat the high temperature through a heating table, and achieve low temperature through a liquid nitrogen condensing tube. Control the temperature of the heating table or the concentration of the liquid nitrogen volatile gas to control the high-low temperature, and use a sealed cavity to maintain the temperature of the device within a predetermined range to avoid the influence of the environment temperature.

[0024] In this embodiment, according to the parameter table, the maximum working temperature of the SiC single tube to be tested is 150℃, and the maximum temperature setting during high temperature testing is 150℃. Adjust the temperature of the temperature control module to 150℃, and the heating table will heat to 150℃. Calculate the high-low temperature holding time according to the weight of the device, which is usually 1 hour at most.

[0025] Debugging: According to the table data, the maximum rated voltage of the device is 750V, and the current is 100A. During debugging, the voltage can be applied first 100V, and the current is applied half about 50A. Compare the voltage and current spikes of the on-off with the maximum rated value 750V and 100A of the device. If it has not reached the maximum rated value, the device is not damaged, the output clamping circuit does not need to be adjusted, and the voltage and current can be continuously increased for debugging.

[0026] If clamping at 750V, no need to adjust the output clamping circuit, but adjust the input voltage spike protection circuit because the input spike is too high. If the clamping voltage is too high, reduce the number of TVS tubes.

[0027] Step S5, automatic test and data analysis: write an automatic device dynamic parameter test program in the test equipment, set parameters such as voltage, current, sampling accuracy, and run the test program to test the dynamic performance index parameters of the device, so that high-speed data acquisition can be realized. Then export and analyze the data.

[0028] After the test is completed, unload the test program, turn off the instrument, disconnect the high-voltage protection and power supply. If low-temperature test is performed, in order to protect the instrument and the device, drying treatment also needs to be performed.

[0029] In summary, the high and low temperature dynamic parameter modular test method of the power semiconductor device of the embodiment of the application solves the problems of multi-packaging adaptation, device test safety and temperature range test limitations on the basis of the traditional high-power device dynamic parameter test through the integration of the modular tooling fixture, the spike filtering circuit and the high and low temperature system: through the modular tooling fixture, the adaptation and rapid test of multiple types and multiple different packages are realized, and the fixture adaptation difficulty problem in the test is solved; through the addition of the spike filtering circuit in the driving circuit, the driving voltage clutter is absorbed, the noise is filtered out, the device voltage waveform is effectively improved, the device test stability and safety problems caused by the too high instantaneous spike voltage are avoided, and the problems that the device is easily damaged by the instantaneous spike voltage and the high and low temperature test result is inaccurate are solved; the high and low temperature system can realize the performance parameter test of the device at-55~175℃, and the problem of inaccurate high and low temperature test of the traditional instrument equipment is solved; through the automatic test equipment, rapid device test is realized, and the test efficiency is significantly improved; compared with the traditional test method, the application breaks through the temperature adaptability limitation and supports wide temperature range test.

[0030] The technical method of the application can be applied to the dynamic parameter test of high-voltage and high-current power devices such as SiC and IGBT, and can also be popularized and applied to other high-power integrated circuit products, and has wide application prospect.

[0031] The above only describes certain exemplary embodiments of the application by way of illustration, without doubt, for ordinary skilled in the art, without departing from the spirit and scope of the application, the described embodiments can be modified in various ways. Therefore, the above figures and description are illustrative in nature and should not be understood as limiting the scope of protection of the claims of the application.

Claims

1. A modular testing method for dynamic parameters of power semiconductor devices at high and low temperatures, characterized in that, include: Step S1: Select the driving resistor and output clamping circuit according to the device parameters of the device under test; select the modular test fixture according to the package structure and device type of the device under test; build the input voltage spike protection circuit according to the device parameters and test type, and install it in the driving circuit of the test fixture. Step S2: Install the test fixture, ensuring that the interface of the test fixture makes reliable and tight contact with the interface of the test equipment; Step S3: Mount the device under test sample onto the test fixture, ensuring that the device pins are in reliable and tight contact with the probes on the test fixture; Step S4: Place the test fixture with the device under test sample installed in the high and low temperature test system, control the temperature of the high and low temperature test system, and keep it at the temperature for a period of time to make the sample temperature stable. Then, perform sample debugging, from low voltage to high voltage, from low current to high current, to ensure that the device voltage and current waveforms are smooth. Step S5: Perform dynamic performance parameter tests on the device to obtain test data.

2. The method as described in claim 1, characterized in that, In step S1, the output clamping circuit is located between the CE terminals of the device and includes multiple TVS diodes connected in series. The number of TVS diodes connected in series is controlled according to the maximum rated voltage of the device.

3. The method as described in claim 2, characterized in that, In step S1, the voltage spike protection circuit includes a capacitor, a resistor, and a diode, wherein the resistor and diode are connected in series and then in parallel with the capacitor; Select a diode with a reverse recovery time of less than 30ns, based on the RC time constant. Select the capacitor and resistor, where R is the gate resistance value, and C is adjusted according to the frequency of the voltage pulse used in the test. The filter center frequency range is between the pulse frequency and the peak frequency.

4. The method as described in claim 3, characterized in that, In step S4, during sample debugging, the difference between the voltage and current spikes during turn-on and turn-off and the maximum rated value of the device is compared. If the maximum rated value is not reached and the device is not damaged, the voltage and current are continued to be applied for debugging; otherwise, the output clamping circuit is adjusted. If the voltage can be clamped at the maximum rated voltage, adjust the input voltage spike protection circuit; if the clamping voltage is too high, adjust the output clamping circuit and reduce the number of TVS diodes.

5. The method according to any one of claims 1-4, characterized in that, In step S1, a driving resistor is selected based on the gate resistance of the device under test, and the resistance is finely adjusted so that a smooth driving current is applied to the gate of the device after passing through the driving resistor.

6. The method according to any one of claims 1-4, characterized in that, In step S3, the Kelvin test program is run to check whether the connection integrity between the device sample and the test equipment is good.

7. The method according to any one of claims 1-4, characterized in that, In step S4, high temperature is achieved through a heating platform, and low temperature is achieved through a liquid nitrogen condenser. High and low temperatures are controlled by controlling the temperature of the heating platform or the concentration of liquid nitrogen vapor. The system temperature is maintained within a predetermined range through a sealed cavity to avoid the influence of ambient temperature.

8. The method according to any one of claims 1-4, characterized in that, In step S4, the temperature is determined based on the device parameters, and the high and low temperature holding time is calculated based on the device weight.

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