Electron-drag effect in Si metal-oxide-semiconductor devices with thin oxide layers

We study theoretically and experimentally the electron-drag effect in silicon metal-oxide-semiconductor field-effect transistors with thin oxide layers. According to a former theoretical prediction the drag effect had to be significantly enhanced by the plasma resonance. However, recent experiments of Solomon and Yang did not confirm this prediction. We show that under the experimental conditions (the doping of the gate 1019cm-3 and more) and room temperature the decay of plasma waves appears to be large and smears the resonance. The electron scattering in the gate is so strong that the energy uncertainty is larger than the temperature and regular microscopic transport theory for gate electrons cannot be used. For the calculation of the drag effect we make use of the method of correlators and describe transport in the gate with the help of phenomenological parameters. This approach gives good agreement with the experiment.