Integrated complementary MOS circuits

The effects of substrate resistivity oxidation cycles on the idling current (IDSO) of n-channel MOS transistors were studied in detail. Devices were fabricated using dry thermal oxide and also pyrolytic oxide for the gate insulator. Devices made using dry thermal oxide for the gate insulator exhibited a large variation in idling current values. A normal distribution of idling current was observed for low values of substrate resistivity and pyrolytically grown gate oxide. Experiments performed show that pyrolytic oxide with phosphorus passivation exhibits a charge storage which corresponds to a surface state density in the range of 5-7 × 10¹¹states / cm².