Substrate effects on metal-oxide single electron transistors electrometer measurements.

This work presents the response of SETs silicon, quartz, and sapphire substrates to applied potential on a second gate SET gate. The SETs used are fabricated using electron beam (e-beam) lithography and the Dolan bridge technique. Measurements are performed at temperature range of 0.3 4.2 K. We observed a breakdown in compensation (seen as CBOs with varied period) in devices on Si substrates but not in devices on the insulating wide bandgap substrates, quartz and sapphire, which have no mobile charges. In these substrates it is possible to achieve an almost ideal charge cancellation over a large range of gate voltages (tens of volts).