Carbon Dissolution for Growing Diamond Films by Solid Epitaxy

THE OBJECTIVE OF THIS RESEARCH IS TO ESTABLISH A METHOD TO GROW SINGLE CRYSTAL DIAMOND FILMS. IN THIS APPROACH, ON A THIN TEMPLATE SUBSTRATE, AN INTERMEDIATE CARBON-DISSOLVING MEDIUM IS DEPOSITED. ON THE FACE OF THIS MEDIUM A CARBON CONTAINED MATERIAL IS INTRODUCED. WHEN THIS SYSTEM IS HEATED TO HIGH TEMPERATURE, ATOMIC CARBON WILL BE SUPPLIED BY THE CARBON-DISSOLVING MEDIUM INTO THE TEMPLATE AND DIAMOND CAN GROW EITHER EPITAXIALLY ON THE FREE SURFACE OF THE TEMPLATE, OR MESOTAXIALLY BETWEEN THE MEDIUM AND THE TEMPLATE. THE REQUIREMENTS FOR THE TEMPLATE ARE: 1) LOW SOLUBILITY OF CARBON IN THE MEDIUM SO THAT ALL CARBON WILL NOT BE TRAPPED IN THE MEDIUM; 2) NO STABLE COMPOUND IS FORMED BETWEEN CARBON AND THE MEDIUM IN THE OPERATING TEMPERATURE REGION; 3) A PROXIMITY TO THE LATTICE CONSTANT OF DIAMOND, AND 4) AN ADEQUATE DIFFUSION RATE AT THE OPERATING TEMPERATURE TO GROW THE DIAMOND EFFICIENTLY. COPPER AND NICKEL ARE EXAMPLE. THE CARBON-DISSOLVING AGENT SHOULD INTERACT WITH CARBON, BUT NOT FORM STABLE HIGH CARBON COMPOUND IN THE OPERATING TEMPERATURE. IRON AND NICKEL ARE EXEMPLES. THIS APPROACH REPRESENTS A BASIC MODIFICATION OF CARBON ION IMPLANTATION BY PRINS ET AL. OR A CARBON DIFFUSION INTO THE TEMPLATE DIRECTLY BY HEATING THAT WE ADVOCATED EARLIER.