SYNTHESIS OF DIAMOND USING PLASMA

• Main Authors: OKADA KATSUYUKI, MATSUMOTO SEIICHIRO, NAGASHIMA TAKASHI, MORIYOSHI YUSUKE
• Format: Patent
• Language: English
• Published: 17.06.1991
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; CHEMISTRY; CRYSTAL GROWTH; METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

PURPOSE:To contrive to improve the grow rate of diamond by generating plasma with an electric power whose amplitude is modulated. CONSTITUTION:A reaction chamber 4 is evacuated with an evacuator 5 and a plasma-generating gas such as Ar gas or H2 gas is fed into the evacuated reaction chamber from a gas-supplying device 6 through a valve 7. After the gas pressure is adjusted to a pressure of 10<-4> to 5X10 atmospheres, an electric power is supplied to the electrode of a plasma torch 1 from a DC electric source 2 to generate plasma in a modulation range of 100Hz-500kHz. A carbon source such as methane is fed into the plasma from a valve 7' on a substrate 3 comprising Mo, Si or Al2O3 heated to 350-1400 deg.C to deposit a diamond film having a desired thickness.