Electrical characterisation of high voltage MOSFETs using MESDRIFT

This paper deals with the degradation mechanisms of 100V Lateral DMOSFETs proposing a new test structure called MESDRIFT, test structure concept designed and fabricated by AMIS, Belgium. This structure presents a small contact smartly engineered at the separation boundary between the intrinsic MOS and drift zone. The contact allows the separate investigation of the parts without altering the overall characteristics of the original device. Experiments; performed on MESDRIFT revealed that hot holes/electrons are injected into the oxide for low/high V_G, high V_D stress conditions. 2D numerical simulations were used to reinforce the theory behind the degradation mechanisms of these devices.