Study of damage mechanism and process of NMOSFET due to high power microwave injected from drain

In this paper a two-dimensional n-channel MOSFET under high power microwave (HPM) electro-thermal simulation model which account for avalanche generation effect and self-heating effect is introduced. According to the theory of PN junction responses to microwave signal and simulation results, an analysis about damage process and mechanism of NMOSFET due to equivalent voltage of HPM injected fro m the drain was done. The results show that temperature rise rapidly near the drain-substrate PN junction because of thermal second breakdown and when reach the melting point of silicon, fuse resistor is formed in the body of device, resulting in the MOS losing the normal function. The experimental result of MOS injected HPM shows the characteristic curve of tested device are consistent with the simulation results, proving that the physical processes and the physical model introduced in the paper are correct.