Research on Thermal Failure Mechanism of IGBT Based on Thermal Balance Analysis

Insulated Gate Bipolar Transistor (IGBT) has different power consumption-temperature characteristics in different temperature stages. Based on the existing steady-state and transient mathematical models of IGBT, the power consumption-temperature curve of IGBT is obtained by considering the relationship between the internal parameters of the device and the physical constants of the material semiconductor and temperature. It is found that the power consumption-temperature curve increases approximately linearly in the low temperature stage and exponentially in the high temperature stage. The stable point, unstable point and critical point of junction temperature are obtained by solving the IGBT power consumption-temperature curve and heat transfer curve simultaneously, and the thermal failure mechanism of IGBT is analyzed based on the positive feedback relationship between IGBT power consumption and junction temperature at the unstable point. Finally, the experimental verification is carried out.