Third-Quadrant Conduction Induced Dynamic R on Effect in GaN Gate-Injection-Transistor

The deterioration of dynamic on-resistance ([Formula Omitted]) and the mechanism of commercial GaN-based gate injection transistors in the third and the first quadrants is studied. In our test condition, the device exhibits an obvious dynamic [Formula Omitted] effect in the half-bridge test circuit under high current conditions that behaves well in the hard-switching test circuit. According to the stress-to-measurement test, we consider that the origin of the dynamic [Formula Omitted] in the half-bridge test circuit is related to the semi-on-state of the device in the third-quadrant conduction. In this state, a peak of the electric field is located at the source edge of the gate, which will cause the traps located in the buffer or the surface to capture electrons. In the on-state, the degree of suppression of dynamic [Formula Omitted] by gate injection current ([Formula Omitted]) is related to the device’s operating quadrants. Based on the TCAD simulation, we consider that this is because the drain voltage of the device affects the distribution of gate injection holes under different operating quadrants.