MECHANISM STUDY OF HOT CARRIER INDUCED DEGRADATION IN LDMOSFET

摘要

Hot Carrier Injection (HCI) behaviors of the two types of LDMOS were investigated in this paper. The inverse degradation behavior of linear drive current and channel transconductance between the two device configurations were characterized. The possible mechanisms were discussed by detailed electric measurement and thorough analysis. Charge pumping measurements and TCAD simulations were performed to verify the channel electric field distribution and the drastic carrier impact ionization zone. The results turn out that with the change of the overlap statues between the gate electrodes and the lateral diffused drift regions, the location of the maximum electric field changed and so did the impact ionization zone.