Anisotropic and damageless etching of single-crystalline silicon using chlorine trifluoride molecular beam

At room temperature, anisotropic etching of both (100) and (111) oriented single-crystalline silicon substrates is successfully achieved, using a thermally excited ClF3 molecular beam. The morphology of the etched surface is better than that using Cl2. The etching rate is more than 50 Å/min, and the ratio of etching rate of vertical direction to that of horizontal direction is more than eight. Process-induced damage in the metal–oxide semiconductor device was not observed from the capacitance–voltage characteristic measurements.