Attojoule MOSFET logic devices using low voltage swings and low temperature

Abstract

Previous estimates of the performance limits of MOSFET logic devices, including the possibility of low temperature operation, have used the conventional static electrical behavior as a starting point. Typically, such studies conclude that the minimum voltage swing is ∼ 200 mV, leading to practical limits on power dissipation and switching speed that prohibit the combination of very low-power dissipation and very high speed achieved in Josephson junction logic. At such low voltages, the device behavior becomes very sensitive to fabrication, making high yields difficult. Here we consider the conditions which must be met to achieve high speed and low power VLSI logic devices through voltage swings ∼ 25 mV. Dynamic logic through bulk conduction devices operating at T ≲ 30K represents the major requirements. At such low temperatures, nonequilibrium processes provide a new basis for device action, and a novel relaxation mode MOSFET operating under carrier freezeout conditions is suggested as a possible low-voltage swing logic switch with power-delay products in the attojoule range.