Silica layers formed on In/sub 0.53/Ga/sub 0.47/As by downstream PECVD

In/sub 0.53/Ga/sub 0.47/As (IGA)-SiO/sub 2/ interfaces are prepared by downstream plasma-enhanced chemical-vapor deposition (PECVD), which avoids exposing the semiconductor surface to the bombardment of the exciting plasma. The natural state of n- and p-type In/sub 0.53/Ga/sub 0.47/As in contact with SiO/sub 2/ prepared by downstream PECVD is electron accumulation. In the case of n-type material, hole accumulation is achieved with negative insulator fields, but for p-MIS structures, Fermi level pinning occurs at 0.41 eV from the valence band edge. Hole accumulation could not be established. The quiescent electron accumulated state of the p-type surface causes surface leakage in junctions that are passivated with this material.<>