Plasma etched polycrystalline hot-filament chemical vapor deposited diamond thin films and their electrical characteristics

Etching of hot-filament, chemical vapor deposited, diamond thin films utilizing low energy ion irradiation was investigated. The films used in this study were boron doped polycrystalline diamond, deposited on p-type (100) oriented silicon substrates. A low voltage dc corona discharge with an oxygen plasma was used to sputter etch the films. Surfaces were investigated by scanning electron microscopy and profilometry. Etch rates were approximately 500 Å/min, depending on the various processing conditions. Characteristics of In/diamond/Si Schottky diodes were used to evaluate the electrical properties of diamond surfaces with various treatments. Results indicate that plasma etching can significantly affect Schottky device characteristics.