AVS 47th International Symposium
    Electronics Tuesday Sessions
       Session EL-TuP

Paper EL-TuP8
Fabrication of Smooth Diamond Films on SiO2 by the Addition of Nitrogen to the Gas Feed in Hot-filament CVD

Tuesday, October 3, 2000, 5:30 pm, Room Exhibit Hall C & D

Session: Poster Session
Presenter: S.F. Durrant, Universidade Estadual de Campinas, Brazil
Authors: V. Baranauskas, Universidade Estadual de Campinas, Brazil
A.C. Peterlevitz, Universidade Estadual de Campinas, Brazil
Z. Jingguo, Universidade Estadual de Campinas, Brazil
S.F. Durrant, Universidade Estadual de Campinas, Brazil
Correspondent: Click to Email
Diamond films of low roughness have been deposited onto thermally oxidized Si substrates by a process of anisotropic crystalline growth induced by nitrogen in a Hot-Filament Chemical Vapor Deposition (HFCVD) reactor. Ethanol (C2H5OH), diluted in hydrogen and nitrogen, was used as the source of carbon. At high concentrations, nitrogen tends to suppress diamond growth in the < 100 > direction, which allows the growth of square mesoscopic crystals of great area in the directions parallel to the surface of the substrate. These mesoscopic structures of low thickness stack upon each other, forming a thick diamond coating of uniform thickness. Analysis of the coatings made by micro-Raman spectroscopy and atomic force microscopy (AFM) revealed that it is possible to obtain diamond coatings of high quality of roughness comparable that of the SiO2 at the diamond/SiO2 interface, and the roughness at the growth surface corresponds to the thickness of the steps of the mesoscopic structures. The microscopic mechanisms that involve the possible passivation of the <100> diamond surface by nitrogen are also discussed.