MICROWAVE PLASMA DIAMOND DEPOSITION AT HIGH GROWTH RATES

BECAUSE OF THE UNIQUE PROPERTIES OF DIAMOND, RECENTLY DEVELOPED CHEMICAL VAPOR DEPOSITED (CVD) DIAMOND THIN FILMS COULD BE USED IN A WIDE VARIETY OF APPLICATIONS FROM ELECTRONICS TO CUTTING TOOLS, INFRARED OPTICS TO ABRASIVES. HIGH QUALITY DIAMOND FILMS ARE PRESENTLY GROWN AT RATES OF ABOUT 1 MICRON/HR. CRUCIAL TO THE SUCCESSFUL COMMERCIALIZATION OF THE TECHNOLOGY IS THE ATTAINMENT OF LARGER GROWTH RATES. ATMOSPHERIC PRESSURE PLASMA TORCHES HAVE BEEN USED TO OBTAIN HIGH DIAMOND GROWTH RATES BUT ARE LIMITED TO SMALL AREAS. A HIGH POWER DENSITY, 1 KW/CM2 AT 200 TORR PRESSURE, MICROWAVE PLASMA DISCHARGE IS PROPOSED HERE TO DEMONSTRATE INCREASED GROWTH RATES BY AT LEAST ONE ORDER-OF-MAGNITUDE. A MICROWAVE DISCHARGE IS CHOSEN BECAUSEOF THE POTENTIAL OF SCALE-UP OF THE DEPOSITION AREA AND THE HIGH QUALITY FILMS WHICH ARE OBTAINED WITH THIS METHOD. A PARAMETER SPACE STUDY IN POWER DENSITY, NEUTRAL PRESSURE, SUBSTRATE TEMPERATURE AND PLASMA CHEMISTRY IS PROPOSED IN A SINGLE REACTOR. THIS WOULD HELP IN THE UNDERSTANDING OF THEMECHANISMS FOR DIAMOND GROWTH. A COMMERCIALLY AVAILABLE HIGH GROWTH RATE DIAMOND REACTOR COULD BE DESIGNED AS A DIRECT CONSEQUENCE OF THIS RESEARCH.