Synthesis of (111) oriented diamond thin films by electrophoretic deposition process

A method for (111) oriented diamond film synthesis has been developed using controlled seeding of micron-sized diamond particles by electrophoresis. Different sizes of diamond powders (0.25 and 5 mu m) were electrophoretically seeded on silicon substrates using diamond suspensions in organic solvents (acetone, methanol, and ethanol). The seeded samples were then consolidated by the hot filament chemical vapor deposition process. Diamond suspension in acetone was found to be the most suitable for obtaining uniform diamond seeding In electrophoresis. A preferred (111) orientation was obtained for a monolayer of 5 mu m seeds. However, when smaller seeds (<1 mu m) were used, randomly oriented films were obtained. The surface morphology, crystal orientation, and quality of diamond films were investigated using scanning electron microscopy, x-ray diffractometry, and Raman spectroscopy. (C) 1997 American Institute of Physics.