Threshold instability in IGFET’s due to emission of leakage electrons from silicon substrate into silicon dioxide

Experimental evidence of a new type of threshold instability in IGFET’s due to the emission of leakage electrons from the silicon substrate into SiO2 is presented. Also presented is a model relating the emission current to the leakage current components of the device. This emission phenomenon could be a serious threshold instability problem at high operating temperatures where the leakage current level is high, especially in devices with a dual dielectric as the gate insulator where the electron trap concentration is very high.