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

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,max), I_B,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, E²PROM cells since the above stress conditions, such as the I_G,max and hot-hole stress, are the major operating conditions for device programming and erasing, respectively