Transport properties of a 100-A crystalline In2O3-x film

Because of its relatively small electron-carrier concentration per unit volume N1020/cm3, the electronic transport properties of In2O3-x are dominated by electron-electron interaction effects owing to reduced electron screening. Weak localization effects are also important. These two processes well describe the behavior of the magnetoconductance data, the resistance versus temperature data in different perpendicular magnetic fields, and the temperature-dependent Hall-constant data in a 2-T field. The temperature-dependent Hall-constant data exhibited a ln(1/T) dependence and yielded a value of 0.75 for the electron screening constant F. Fits to the low-magnetic-field magnetoconductance data yielded values for the inelastici, the spin-orbit so, and the magnetic impurity s scattering times. Both so and s are long (weak scattering processes) and took on values of so=7.6×10-11 sec and s=7.3×10-11 sec, whereasi(sec)=133×10-12/T could be well described by the Nyquist formula of Altshuler and co-workers. The high-field, low-temperature, magnetoconductance data were characterized by a negative interaction contribution int, and experimental values for int at 0.5 K agreed well with the interaction theory of Lee and Ramakrishnan. The resistance versus temperature data could be nicely explained using both the 2D interaction and 2D weak localization theories for the conductivity; no adjustable parameters were used in the fitting of the resistance and magnetoconductance data.