A model for reverse short channel effect and capacitance-voltage characteristics

A new model for simulating the reverse shea channel effect and capacitance- voltage (C-V) characteristics of metal-oxide-semiconductor (MOS) transistor s has been developed. Due to ion-implantation and stress effects, the inter face between Si and SiO2 in the model described here has been assumed to be a nonuniform sink of interstitials. The simulator ALAMODE and the two-dime nsional (2D) process simulator TSUPREM4 were used to simulate doping profil es of n-channel MOS (NMOS) devices. Using simulated 2D doping profiles, the threshold voltage and C-V curves of NMOS devices were calculated. We show comparisons of the threshold voltage, C-V curves, and channel doping profil es for extracted profiles using inverse modeling techniques and those simul ated by ALAMODE and TSUPREM4. Using default model parameters in TSUPREM4, t he doping profiles did not match extract ed doping profiles well, but with the model described here incorporated into TSUPREM4 using calibrated model parameters, a good match between measurements and simulations was observed. The body effect and C-V characteristics of NMOS devices are quantitatively predicted using parameters obtained from matching of experimental threshol d voltage data. We describe the model and implementation and discuss the ph ysical significance of the new model. (C) 1999 The Electrochemical Society. S0013-4651(98)07-041-4. All rights reserved.