Patent ID: 10468246

Abstract:
A method of preparing a diamond crystal substrate for epitaxial deposition thereupon of a delta doping layer includes preparing an atomically smooth, undamaged diamond crystal substrate surface, which can be in the (100) plane, by polishing the surface and then etching the surface to remove subsurface damage caused by the polishing. The polishing can include a rough polish, for example in the (010) direction, followed by a fine polish, for example in the (011) direction, that removes the polishing tracks from the rough polishing. After etching the polished face can have a roughness Sa of less than 0.3 nm. An inductively coupled reactive ion etcher can apply the etching at a homogeneous etch rate using an appropriate gas mixture such as using argon and chlorine to remove between 0.1 and 10 microns of material from the polished surface.