A unified approach to profiling the lateral distributions of both oxide charge and interface states in n-MOSFET's under various bias stress conditions

Abstract

A new and accurate technique that allows the simultaneous determination of the spatial distributions of both interface states (N-it) and oxide charge (Q(ox)) will be presented. The gated-diode current measurement in combination with the gate-induced drain leakage (GIDL) current were performed to monitor the generation of both N-it and Q(ox) in n-MOSFET's. A special detrapping technique and simple calculations have been developed, from which the spatial distributions of both N-it and Q(ox) under various bias stress conditions, such as the hot-electron stress (I-G,I-max), I-B,I-max, and hot-hole stresses, can be determined. The calculation of gated-diode current by incorporating the extracted profiles of N-it and Q(ox) has been justified from numerical simulation. Results show very good agreement with the experimental results. The extracted interface damages for hot-electron and hot-hole stresses have very important applications for the study of hot-carrier reliability issues, in particular, on the design of flash EPROM, (EPROM)-P-2 cells since the above stress conditions, such as the I-G,I-max and hot-hole stress, are the major operating conditions for device programming and erasing, respectively.