Compared to conventional silicon (Si), silicon carbide (SiC) has several superior qualities that make it far more useful for power electronic applications. SiC has a significantly larger bandgap (3.26 eV) than Si (1.12 eV), which results in a greater breakdown voltage and allows devices to withstand higher temperatures and voltages. SiC devices can function at junction temperatures beyond 200°C thanks to their large bandgap, which is far greater than Si's maximum of about 150°C. Moreover, SiC has a greater thermal conductivity (3.7 W/cm·K) than Si (1.5 W/cm·K), which enables more effective heat dissipation and, consequently, lessens the requirement for large cooling systems. Higher electron mobility in SiC leads to decreased energy losses during switching and quicker switching rates. These characteristics of SiC improve the performance, efficiency, and dependability of SiC-based devices, which makes them perfect for high-frequency, high-power, and high-temperature applications including industrial power supply, electric vehicles, and renewable energy systems.Despite of advantages of SiC, the SiC MOSFETs and power modules have many reliability challenges even having many benefits but are needed to be resolved before they are widely used. The SiC MOSFETs' gate oxide layer is more prone to deterioration than its silicon (Si) counterpart's, which can eventually cause problems like higher leakage currents and unstable threshold voltages. Another crucial issue is the heating in SiC. Although SiC can function at higher temperatures, the resulting thermal stresses can hasten material deterioration and interconnect and packaging failure. Furthermore, SiC power modules may experience time-dependent dielectric breakdown and electrothermal aging as a result of prolonged exposure to high voltage and high temperature. Robust solder junctions and die attach materials—which are prone to wear and failure under heat cycling—are also required by the demanding working conditions. If SiC devices are consistent and durable in demanding applications, rigorous testing and enhanced manufacturing procedures are needed to address these dependability challenges that ensure the reliability of MOSFETs and Modules.To verify that the SiC MOSFET parameters provided in the datasheet are accurate, we used LTSPICE for both static and dynamic modeling. Using factors like threshold voltage, on-resistance, and leakage current, a thorough simulation of the MOSFET's I-V characteristics was created as part of the static modeling process. We were able to replicate the behavior of the device under different voltage and current situations by using the datasheet data into LTSPICE, and this allowed us to confirm that the device fulfilled predicted performance standards. We concentrated on the SiC MOSFET's switching properties for dynamic simulation. This involved studying the impact of parasitic capacitances and inductances on switching transients, as well as modeling turn-on and turn-off periods. We verified the device's speed and efficiency by comparing the simulation results with the switching timings and loss metrics listed in the datasheet. We were also able to look at how temperature changes and thermal impacts affected both static and dynamic performance using the LTSPICE models. We were able to confirm that the SiC MOSFET's simulated performance nearly matched the datasheet parameters thorough simulations in LTSPICE, giving us confidence in its dependability and appropriateness for high-performance applications.The second part of our research, concentrated on diagnosing and verifying the reliability of SiC MOSFETs and power modules. To assess the robustness and stability of these devices' functioning under varied stress scenarios, we conducted several tests in Reliability Lab. To begin with, The SiC MOSFETs were subjected to continuous reverse voltage stress over a minimum of 1000 hours of dynamic reverse bias testing to evaluate the switching characteristics. To replicate actual working circumstances, this test comprised turning the device on and off while supplying a reverse bias voltage. Monitoring any changes in important parameters including breakdown voltage, reverse leakage current, and threshold voltage shift was the goal. To ensure that the devices could resist long-term operating pressures without suffering substantial performance deterioration, extended exposure to dynamic reverse bias helped uncover probable degradation processes, such as hot carrier injection and gate oxide wear-out.SiC power modules were put through power cycle testing to assess their mechanical and thermal resilience to cyclic thermal loads. To simulate the thermal strains seen during real operation, the modules were put through power cycling at various temperatures. The DUTs must be heated and cooled frequently to mimic power application on-off cycles. To understand the impacts on die, attach materials, solder junctions, and other packaging components, several temperature extremes were tested. The test was designed to identify issues like thermal runaway, delamination, and solder fatigue. We were able to learn more about the power modules' resilience and thermal management by examining the number of cycles till failure and figuring out the failure modes.To assess the dependability of the gate oxide under electrical stress, dynamic gate stress testing was carried out at both room temperature and high temperatures. To stress the gate oxide and check its integrity, a sequence of gate voltage pulses with different amplitudes and durations were applied. Measurements were made of parameters including transconductance, threshold voltage shift, and gate leakage current to look for any indications of gate oxide deterioration. Because high temperatures can expose probable failure mechanisms more rapidly and accelerate aging processes, testing at higher temperatures was very crucial. This test verified that the gate oxide could continue to function and be intact throughout a range of temperature ranges and long durations of time.The present research analyzed the partial discharge (PD) behavior of ACEPACK DRIVE SiC power module to determine its insulating endurance in high-stress environments. The study includes characterizations of sinusoidal, DC, and square waveforms to investigate PD behavior under various electrical and temperature stress situations. While DC characterization showed no significant impacts, sinusoidal and square wave characterizations provided different responses, emphasizing the importance of waveform type in PD dynamics. For example, sinusoidal waveforms frequently generate periodic PD patterns, whereas PWM waveforms provide higher-frequency components and steeper voltage transitions, resulting in greater dV/dt, which might worsen PD activity. These distinctions are crucial in understanding how the module operates in a variety of real-world scenarios, such as automotive or industrial applications where these waveforms are frequently encountered.The study revealed that power cycling had no effect on partial discharge Inception voltage (PDIV), indicating that the module's insulation could withstand prolonged electrical and thermal stress. Variations in PDIV were primarily caused by manufacturing variables rather than cycling-related deteriorations. This indicates the module's insulating stability and dependability, making it excellent for high-demand applications, particularly electric and hybrid car systems that require long-term durability.These extensive reliability testing experiments gave us a thorough grasp of the durability and endurance of SiC MOSFETs and Power Modules. Through the identification of plausible failure causes and their commencement under conditions, it might potentially boost the long-term dependability of their SiC devices through design and manufacturing enhancements.

(2025). DIAGNOSTIC AND RELIABILITY ASSESSMENT OF ELECTRONIC COMPONENTS AND POWER MODULES FOR AUTOMOTIVE APPLICATION.

DIAGNOSTIC AND RELIABILITY ASSESSMENT OF ELECTRONIC COMPONENTS AND POWER MODULES FOR AUTOMOTIVE APPLICATION

AKBAR, Ghulam
2025-02-01

Abstract

Compared to conventional silicon (Si), silicon carbide (SiC) has several superior qualities that make it far more useful for power electronic applications. SiC has a significantly larger bandgap (3.26 eV) than Si (1.12 eV), which results in a greater breakdown voltage and allows devices to withstand higher temperatures and voltages. SiC devices can function at junction temperatures beyond 200°C thanks to their large bandgap, which is far greater than Si's maximum of about 150°C. Moreover, SiC has a greater thermal conductivity (3.7 W/cm·K) than Si (1.5 W/cm·K), which enables more effective heat dissipation and, consequently, lessens the requirement for large cooling systems. Higher electron mobility in SiC leads to decreased energy losses during switching and quicker switching rates. These characteristics of SiC improve the performance, efficiency, and dependability of SiC-based devices, which makes them perfect for high-frequency, high-power, and high-temperature applications including industrial power supply, electric vehicles, and renewable energy systems.Despite of advantages of SiC, the SiC MOSFETs and power modules have many reliability challenges even having many benefits but are needed to be resolved before they are widely used. The SiC MOSFETs' gate oxide layer is more prone to deterioration than its silicon (Si) counterpart's, which can eventually cause problems like higher leakage currents and unstable threshold voltages. Another crucial issue is the heating in SiC. Although SiC can function at higher temperatures, the resulting thermal stresses can hasten material deterioration and interconnect and packaging failure. Furthermore, SiC power modules may experience time-dependent dielectric breakdown and electrothermal aging as a result of prolonged exposure to high voltage and high temperature. Robust solder junctions and die attach materials—which are prone to wear and failure under heat cycling—are also required by the demanding working conditions. If SiC devices are consistent and durable in demanding applications, rigorous testing and enhanced manufacturing procedures are needed to address these dependability challenges that ensure the reliability of MOSFETs and Modules.To verify that the SiC MOSFET parameters provided in the datasheet are accurate, we used LTSPICE for both static and dynamic modeling. Using factors like threshold voltage, on-resistance, and leakage current, a thorough simulation of the MOSFET's I-V characteristics was created as part of the static modeling process. We were able to replicate the behavior of the device under different voltage and current situations by using the datasheet data into LTSPICE, and this allowed us to confirm that the device fulfilled predicted performance standards. We concentrated on the SiC MOSFET's switching properties for dynamic simulation. This involved studying the impact of parasitic capacitances and inductances on switching transients, as well as modeling turn-on and turn-off periods. We verified the device's speed and efficiency by comparing the simulation results with the switching timings and loss metrics listed in the datasheet. We were also able to look at how temperature changes and thermal impacts affected both static and dynamic performance using the LTSPICE models. We were able to confirm that the SiC MOSFET's simulated performance nearly matched the datasheet parameters thorough simulations in LTSPICE, giving us confidence in its dependability and appropriateness for high-performance applications.The second part of our research, concentrated on diagnosing and verifying the reliability of SiC MOSFETs and power modules. To assess the robustness and stability of these devices' functioning under varied stress scenarios, we conducted several tests in Reliability Lab. To begin with, The SiC MOSFETs were subjected to continuous reverse voltage stress over a minimum of 1000 hours of dynamic reverse bias testing to evaluate the switching characteristics. To replicate actual working circumstances, this test comprised turning the device on and off while supplying a reverse bias voltage. Monitoring any changes in important parameters including breakdown voltage, reverse leakage current, and threshold voltage shift was the goal. To ensure that the devices could resist long-term operating pressures without suffering substantial performance deterioration, extended exposure to dynamic reverse bias helped uncover probable degradation processes, such as hot carrier injection and gate oxide wear-out.SiC power modules were put through power cycle testing to assess their mechanical and thermal resilience to cyclic thermal loads. To simulate the thermal strains seen during real operation, the modules were put through power cycling at various temperatures. The DUTs must be heated and cooled frequently to mimic power application on-off cycles. To understand the impacts on die, attach materials, solder junctions, and other packaging components, several temperature extremes were tested. The test was designed to identify issues like thermal runaway, delamination, and solder fatigue. We were able to learn more about the power modules' resilience and thermal management by examining the number of cycles till failure and figuring out the failure modes.To assess the dependability of the gate oxide under electrical stress, dynamic gate stress testing was carried out at both room temperature and high temperatures. To stress the gate oxide and check its integrity, a sequence of gate voltage pulses with different amplitudes and durations were applied. Measurements were made of parameters including transconductance, threshold voltage shift, and gate leakage current to look for any indications of gate oxide deterioration. Because high temperatures can expose probable failure mechanisms more rapidly and accelerate aging processes, testing at higher temperatures was very crucial. This test verified that the gate oxide could continue to function and be intact throughout a range of temperature ranges and long durations of time.The present research analyzed the partial discharge (PD) behavior of ACEPACK DRIVE SiC power module to determine its insulating endurance in high-stress environments. The study includes characterizations of sinusoidal, DC, and square waveforms to investigate PD behavior under various electrical and temperature stress situations. While DC characterization showed no significant impacts, sinusoidal and square wave characterizations provided different responses, emphasizing the importance of waveform type in PD dynamics. For example, sinusoidal waveforms frequently generate periodic PD patterns, whereas PWM waveforms provide higher-frequency components and steeper voltage transitions, resulting in greater dV/dt, which might worsen PD activity. These distinctions are crucial in understanding how the module operates in a variety of real-world scenarios, such as automotive or industrial applications where these waveforms are frequently encountered.The study revealed that power cycling had no effect on partial discharge Inception voltage (PDIV), indicating that the module's insulation could withstand prolonged electrical and thermal stress. Variations in PDIV were primarily caused by manufacturing variables rather than cycling-related deteriorations. This indicates the module's insulating stability and dependability, making it excellent for high-demand applications, particularly electric and hybrid car systems that require long-term durability.These extensive reliability testing experiments gave us a thorough grasp of the durability and endurance of SiC MOSFETs and Power Modules. Through the identification of plausible failure causes and their commencement under conditions, it might potentially boost the long-term dependability of their SiC devices through design and manufacturing enhancements.
feb-2025
Silicon Carbide; SiC MOSFET; Power Modules; Reliability Testing; Partial Discharge Phenomenon; SPICE Modelling; Electrical Stress Analysis.
(2025). DIAGNOSTIC AND RELIABILITY ASSESSMENT OF ELECTRONIC COMPONENTS AND POWER MODULES FOR AUTOMOTIVE APPLICATION.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10447/671787
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