Extraction of η parameter characterising μeff against Eeff curves in strained Si nMOS devices

The eta parameter characterising the mu_eff(E_eff) curves in strained Si nMOS transistors is extracted for the first time. It is found that eta is about 45% higher than in unstrained devices. Therefore, using a standard eta value (0.5) instead of the real one implies underestimation of mobility at a high effective field and, in turn, systematic error in surface roughness determination in strained Si devices.