Abstract: The two-dimensional numerical analysis using constant approximation, obtained by Chung and Sah, has been improved by adopting the mobility model. It is found that the slope of the oonduotanoe-gate voltage curve changes from increase to decrease with increasing gate voltage, and the narrow-gate shift of the threshold voltage is larger than that obtained from constant mobility approximation. A new model is proposed here to predict the narrow-gate shift of the threshold voltage. When the conduotanoe-gate voltage characteristics of one narrow-gate MOSPET and one wide-gate MOSFET are got from 2-D numerical analysis or experimental measurement, the threshold voltage shift of any other.narrow-gate MOSFET can then be determined subsequently. This model is checked -and agrees well with the 2-D numerical and experimental results.

Key words: MOSFET, narrow-gate effect