Bulk and surface degradation mode in 0.35 mu m technology gg-nMOS ESD protection devices.

We study failure mechanisms in 0.35 mu m process grounded-gate nMOS electro static discharge (ESD) protection devices stressed by high current - ESD li ke - pulses. Stress evolution of leakage current and low frequency noise is correlated with the position of the ESD damage analyzed using optical beam induced current (OBIC) technique. While a kink-free-like IV characteristic s and low noise magnitude are typical for a bulk damage at the drain-contac t region, a kink-like IV shape and large random telegraph signal (RTS) nois e accompanies surface damage under the gate oxide. The Pole of hot-carriers in the degradation of the Si/SiO2 interface and gate oxide, and leakage cu rrent mechanism are discussed. (C) 2000 Elsevier Science Ltd. All rights re served.