The Neutral Level of Si-Si0 sub 2 Interface States (NOT KNOWN IF TALK GIVEN BECAUSE AUTHOR HAS LEFT AT&T)

The absolute value of the charge Q sub (it) and the neutral level E sub o of interface states play important roles in determining the barrier heights of Schottky diodes and the threshold voltages of MOS field-effect transistors [1]. In 1947 Bardeen [2] suggested that the experimentally observed anomalous insensitivity of the Schottky barrier height to the metal contact is caused by pinning of the metal fermi level to the neutral level of interface states. Since then several studies have related observed deviations from ideality of the temperature dependent current-voltage characteristics to these interface states. However the measured barrier heights are not very reproducible, largely due to variability in sample preparation, and consequently it is difficult to extract the neutral level E sub o with any precision from these data [3].