An improved definition for the onset of heavy inversion in an MOS structure with nonuniformly doped semiconductors

The criterion for the onset of heavy inversion in an MOS structure with nonuniformly doped semiconductors on the basis of an appropriate definition has been derived. The present theoretical model is based upon the improved depletion approximation presented previously by one of authors [ 1]. The validity of the present criterion is confirmed compared with the results obtained from the present model and those obtained from the numerical solutions by assuming appropriate impurity distributions as a test sample. The results obtained from the present model are in excellent agreement with the numerically computed results.