METHOD AND DEVICE FOR SYNTHESIZING DIAMOND BY PHOTOCHEMICAL DEPOSITION

PURPOSE:To synthesize the crystal and the thin film of diamond under low pressure and temps., at a high velocity, and with low energy consumption as compared with the usual thermochemical deposition synthesis by irradiating high- output ultraviole light to a hydrocarbonaceous reaction gas. CONSTITUTION:The high-output light in ultraviolet and vacuum ultraviolet regions, especially laser light or coherent light, radiated from a high-output ultraviolet light generator 1 is passed through a reflector 2 and a condenser lens 3, and condensed through a window 10 on a substrate 5 placed in a reactor 4. Hydrocarbon or a mixed gas of hydrocarbon and hydrogen is supplied into the reactor 4 from a reaction gas supply device 8. The hydrocarbon is decomposed by the ultraviolet and vacuum ultraviolet light, and liberated carbon atoms are deposited on the substrate 5. And a diamond crystal is grown on the substrate 5. Since the quality and the growing velocity, etc. of the diamond crystal depend on the temp. of the substrate, a heater 6 for heating is furnished below the substrate 5 to optimize the substrate temp. The temp. of the heater 6 is controlled by a temp. controller 7.