Magnetoresistance in Si metal-oxide-semiconductor field-effect transitors: Evidence of weak localization and correlation

We have studied the magnetoresistance in the two-dimensional electron gas of silicon metal-oxide-semiconductor field-effect transistor inversion layers at temperatures down to 50 mK. Both low- and high-mobility samples have been studied and clear evidence for localization as well as correlation effects is observed in the region of resistance R_10 k/. From detailed fits of the data at low magnetic fields a localization parameter as well as the temperature dependence of the inelastic scattering rate is extracted. From the data we conclude that the dominant inelastic scattering mechanism at these temperatures is electron-electron scattering in the dirty limit. At higher fields correlation effects dominate and the associated parameters are determined.