Selective deposition of diamond films

Polycrystalline diamond films have been selectively deposited on a silicon surface. A novel process was developed which exposes a patterned, scratch damaged silicon area, surrounded by SiO₂, to a high pressure microwave plasma of hydrogen containing methane. The hydrogen plasma dissociates the methane injected into the reaction chamber, resulting in diamond deposition, which occurs only on the exposed silicon. Under the process conditions described in this work, some in situ plasma etching of the oxide is observed, resulting in little or no growth of diamond in unwanted areas, and further enhancing the selectivity. A variety of patterns and structures have been fabricated. Raman spectroscopy confirmed the films were diamond.