Temporally- and Spatially-Resolved Observations of Current Filament Dynamics in Insulated Gate Bipolar Transistor Chip During Avalanche Breakdown

Two-dimensional imaging of the dynamics of current filaments generated in Insulated Gate Bipolar Transistor (IGBT) chip at room temperature during avalanche breakdown has been performed. The images were obtained by using the Hamamatsu TriPHEMOS equipped with the micro-channel plate (MCP) sensor. The equipment can operate in single photon counting mode. From obtained image series, at the beginning of the avalanche breakdown, the emission intensity at the corners in the edge termination region of the IGBT was found to be high. The pixels with high emission intensity of these corners moved to the center of the four sides of the IGBT shape in the latter half of the avalanche breakdown period. Assuming that these pixels with high emission intensity are attributable to the current filament, it shows that the current filaments are moving at a speed of about 0.9 mm/μs.