Estimation of the impurity redistribution in silicon substrates from MOSFET characteristics

The impurity redistribution in silicon substrates of MOSFET's is estimated from the measurement of dc voltage-current characteristics using the exact theory of the effect of substrate bias. The usefulness of the present method depends upon the acceptability of substituting the Fermi potential before thermal treatments for that after thermal treatments, which then allows for the direct calculation of the impurity concentration. The accuracy of the present method is given theoretically by the discussion of relative errors.