Extraction of the physical oxide thickness using the electrical characteristics of MOS capacitors

Abstract

The physical oxide thickness of ultrathin oxides is extracted using the tunneling current characteristics of MOS capacitors. An extraction tool has been developed for the semiautomatic extraction. The tool implements a nonlinear least square solver and GUIs. A tunneling current model is incorporated into the MIDSIP-T device simulator and it is used as a core simulator of the extraction system. It is found that the transition layer should be considered in the extraction of very thin oxide thickness below 4 nm. A unified parameter set, /spl phi//sub b/=3.3 eV and m/sub c//sup *//m/sub 0/=0.41, is obtained after the extraction of various samples.