Asymmetry in effective-channel length of n- and p-MOSFETs

A fundamental asymmetry is shown to be present in the effective-channel lengths of n-FET and p-FET devices. Basic differences in electron and hole transport give rise to a larger Leff for n-FETs. This can also be observed through a comparison of the device sheet resistance where the relative difference in channel to source/drain mobility leads to distinct sheet rho patterns near the metallurgical junction.