Amorphous silicon photodiode with sloped sidewalls and method of fabrication

摘要

Solid state photodetectors having amorphous silicon photodiode bodies with sloped sidewalls allowing for deposition of high integrity conformal layers thereover are produced by etching the amorphous silicon in a mostly anisotropic etchant in a reactive ion etcher in which the pressure of the etchant is controlled. A photoresist mask having sloped sidewalls is formed over the amorphous silicon to be etched and the pressure of the etchant is selected to produce the desired slope of the sidewall in the photodetector body; at lower pressures a smaller slope is produced in the silicon and at higher pressures a steeper slope is produced in the silicon.