Evidence for multiple impurity bands in sodium-doped silicon MOSFETs

Abstract

We report measurements of the temperature-dependent conductivity in a silicon metal-oxide-semiconductor field-effect transistor that contains sodium impurities in the oxide layer. We explain the variation of conductivity in terms of Coulomb interactions that are partially screened by the proximity of the metal gate. The study of the conductivity exponential prefactor and the localization length as a function of gate voltage have allowed us to determine the electronic density of states and has provided arguments for the presence of two distinct bands and a soft gap at low temperature.

4 pages; 5 figures; Published in PRB Rapid-Communications

References in corpus (2)

• Effect of screening of the Coulomb interaction on the conductivity in the quantum Hall regime
• Shallow Coulomb Gap and Weak Level-Level Correlations in a Deeply Insulating Electron System with Interactions

Cited by in corpus (5)

• Impurity conduction in phosphorus-doped buried-channel silicon-on-insulator field-effect transistors
• Disorder and electron interaction control in low-doped silicon metal-oxide-semiconductor field effect transistors
• Activation mechanisms in sodium-doped Silicon MOSFETs
• Magnetoconductivity of Hubbard bands induced in Silicon MOSFETs
• Variation of the hopping exponent in disordered silicon MOSFETs