Investigation of the proportional difference characteristics of MOSFETs

A proportional difference operator method has been presented to study the electrical characteristics of MOSFETs in all the operating regimes. It is shown that the proportional difference drain current versus the drain voltage exhibits a spectrum feature in all regions of operation including the subthreshold regime and the saturation regime. The amplitude of the spectrum peak is related to the effective carrier mobility, and the spectrum peak position responds to the voltage constants in each operating region (including the subthreshold and saturation regime) of a MOSFET. This then enables the more important statistic performance of MOSFETs to be evaluated using the proportional difference operator method. Analytical expressions for computing these parameters (such as effective carrier mobility, thermal voltage, threshold voltage etc.) have been derived and experimental results have been presented.