Temperature dependence of the conductivity of a silicon inversion layer at low temperatures

The temperature dependence of the conductivity of a high-mobility silicon MOSFET is reported for temperatures from 0.2 to 23 K and electron densities from 1 to 20 × 10¹¹cm⁻². The results show a strong increase in conductivity with decreasing temperature. However, this rate of increase was observed to rapidly diminish outside of a restricted range of temperature for a given density. The decreasing temperature dependence at the lower temperatures is attributed to the saturation of screening as the effects of broadening become comparable to thermal effects. The diminishing temperature dependence at the higher temperatures puts limits on the applicability of recent calculations for the conductivity.