TUNNELING INTO INTERFACE STATES OF MOS STRUCTURES

Abstract

Measurements of the dc conductance of Si‐SiO₂–(Cr+Au) devices using P⁺⁺‐type Si and thin oxide layers (<50 Å) show one to two orders of magnitude increase of dc conductance of tunneling into the forbidden semiconductor band by changing from dry oxygen grown to steam grown and to annealed steam‐grown oxide layers. The effect is explained by a corresponding increase of interface state density well known for thicker oxide layers (≈ 1000 Å).