Carrier separation and Vth measurements of W-La2O3 gated MOSFET structures after electrical stress

Abstract

Using a W-La 2 O 3 gated MOSFET structure, we report the effect of substrate and gate injection of electrons on the breakdown and electrical degradation characteristics of the gate stack. Using the carrier separation measurement technique, we are able to identify the major contributor to leakage current under various stress conditions. By stressing n-and p-channel MOSFETs with positive and negative gate voltages respectively, the degradation (Vth shift) after stress is obtained and compared to the polarity of the applied stress. Keywords