Enhanced Hot-Carrier Induced Degradation In STi Isolated NMOS Transistors

摘要

An analysis of the hot-carrier reliability in Shallow Trench Isolation(STI) isolated NMOS transistors is presented. The influence of STI on NMOS transistor lifetime is investigated, with specific test structures. It is shown that STI induces an enhanced hot-carrier induced degradation at the channel edges, responsible for a decrease in the transistor lifetime. 3D device simulations have demonstrated a large increase in the vertical electric field in these regions, as compared to the channel center. Moreover, an anomalous lifetime degradation for ultra narrow channel width is shown and discussed.