The drift/diffusion ratio of the MOS transistor drain current

The paper presents a new method to evaluate the ratio between the two components of drain current in MOS transistors: drift and diffusion. By setting certain limits for this ratio, the moderate inversion region can be delimited in transfer electrical characteristics. The limits of the moderate inversion give the possibility for a more accurate applying of the continuous models. Some examples are given by extracting the main model parameters for a sub-micron MOS transistor and the limits of moderate inversion are compared with the results obtained using other models.