Abstract: The substrate in a plasma jet deposition system is provided with structural attributes, such as apertures and/or grooves, that facilitate efficient deposition. Groups of substrates are arranged with respect to the plasma beam in a manner which also facilitates efficient deposition. In addition to increasing the portion of the plasma beam volume which contacts the substrate surface or surfaces, it is advantageous to provide for the efficient evacuation of spent fluids away from the substrate so that fresh plasma containing the operative species can easily and continuously contact the substrate surface.

Abstract: In a first embodiment of an improved diamond deposition cell, a chamber is evacuated to a low pressure and a graphite element in the chamber is heated to a selected high temperature and heats a substrate positioned within the chamber spaced by a selected gap from the graphite body to a selected lower temperature. Hydrogen or a mixture of hydrogen and hydrocarbon gas is admitted to the chamber and part of the hydrogen reacts with the hot graphite body to form atomic hydrogen and hydrocarbon gasses. Hydrogen and hydrocarbon gasses cycle repeatedly across the gap between the facing surfaces of the body and the substrate in the kinetic regime resulting in a net transfer of carbon to the substrate and its deposition as diamond crystals or film on the substrate. In a second embodiment, the graphite body is heated by combusting gasses in a cavity therein.