Abnormal Increment Substrate Current After Hot Carrier Stress in n-FinFET

This letter investigates the mechanism of abnormal substrate current (Isub) after hot carrier stress (HCS) in fin field effect transistors (FinFETs). Traditionally, after HCS, the drain current andIsubof the saturation region will continue to decrease. In this work, however,Isubfirst decreased and then exhibited a gradual abnormal rise. This abnormalIsubbehavior was investigated by different measurement methods and was determined to be due to trap-assisted tunneling. This study first uses different operating voltages to prove the proposed model, then applies a variable temperature stress condition to confirm the model. Finally, a junction current measurement is used to determine the location of defect generation.