Effect of diffusion current on characterising the effective channel length of nanometre-scaled n-MOSFETs

The diffusion current in nanometre-scale MOSFETs operated in the triode region is no longer negligible. A factor of s(I_diff+I_drift)/I_drift is introduced in extracting the effective channel length and series resistance of the MOSFET with the commonly used shift and ratio method. The results reveal that the extracted value for s > 1 (considering the diffusion current) is closer to the actual situation than the extracted value with s= 1 (neglecting the diffusion current).