Method of manufacture of free standing microwave plasma CVD polycrystalline diamond films with major dimensions on the order of one wavelength

• Main Authors: Elgin E Eissler, David Sabens, Charles D Tanner
• Format: Patent
• Language: English
• Published: 04.10.2017
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; BASIC ELECTRIC ELEMENTS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; CRYSTAL GROWTH; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRICITY; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; 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; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

A chemical vapour deposition (CVD) reactor 20 comprises a resonating cavity 24, a microwave transparent window 30 separating the cavity into an upper zone 28 and a plasma zone 26, a substrate 10 disposed proximate a bottom of the plasma zone opposite the window and a ring structure 2 positioned around a perimeter of the substrate and including a lower section 16 extending from the bottom of the resonating cavity towards the microwave transparent window and an upper section 14 on a side of the lower section opposite the bottom of the resonating cavity extending radially towards a central axis of the ring structure. The lower section of the ring structure may comprise a plurality of holes (22, figure 9) or slots (22, figure 2). The upper section of the ring structure may comprise a channel (54, figure 9) in fluid communication with a fluid source. In use, the ring structure focusses microwaves in the reactor. A method of microwave plasma CVD growth of a diamond film on a substrate using said reactor comprises feeding a carbon bearing reactive gas into the plasma zone and concurrently feeding microwaves into the resonant cavity. An as-grown diamond film grown by microwave plasma CVD (MPCVD) is also disclosed.