Electron beam assisted chemical etching of single-crystal diamond substrates with hydrogen gas

The electron beam assisted chemical etching (EBACE) method with hydrogen gas is applicable to direct fine patterning of single-crystal diamond substrates. A scanning electron microscope (SEM) combined with a gas introduction system was used for EBACE. Hole, line and rectangular patterns were successfully fabricated. In the case of fabrication of the rectangular pattern, the etched depths are proportional to the electron dose. The etching rate using oxygen gas is faster than that using hydrogen gas. Raman scattering was used to confirm whether amorphous carbon was formed on the etched areas. The obtained Raman spectra indicate that areas etched using both hydrogen gas and oxygen gas do not form amorphous carbon.