The effect of electrostatic screening on a nanometer scale electrometer.

We investigate the effect of electrostatic screening on a nanoscale silicon MOSFET electrometer. We find that screening by the lightly doped p-type substrate, on which the MOSFET is fabricated, significantly affects the sensitivity of the device. We are able to tune the rate and magnitude of the screening effect by varying the temperature and the voltages applied to the device, respectively. We show that despite this screening effect, the electrometer is still very sensitive to its electrostatic environment, even at room temperature.