The effect of electrical conduction of Si3N4on the discharge of MNOS memory transistors

Abstract

It is proposed that the discharge of MNOS memory devices proceeds through a combination of direct tunneling from charge traps in the silicon nitride into the silicon, and charge migration through the nitride by a series of Poole-Frenkel emission-drift-capture events. The discharge of MNOS transistors calculated from this model by computer agrees well with experimental data taken at elevated temperatures on SOS/MNOS devices with LPCVD nitrides. Parameter values used indicate a very low value of electron mobility. The discharge rate at elevated temperatures is predicted to be sensitive to whether the silicon under the gate is in accumulation or depletion during the discharge.