Accession Number : ADA300163

Title :   Selected Energy Epitaxial Deposition and Low Energy Electron Microscopy of AlN, GaN, and SiC Thin Films.

Descriptive Note : Quarterly technical rept. 1 Jul-30 Sep 95,

Corporate Author : NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF MATERIALS SCIENCE AND ENGINEERING

Personal Author(s) : Davis, R. F. ; Lamb, H. H. ; Tsong, I. S. ; Bauer, E. ; Doak, R. B.

PDF Url : ADA300163

Report Date : SEP 1995

Pagination or Media Count : 35

Abstract : At North Carolina State University, GaN films have been deposited on Al2O3((0001) substrates at 550 deg C using triethylgallium and NH3 seeded free jets. An NH3 to triethylgallium ratio of 151 yielded the best GaN films in this configuration. Experiments to determine the optimal skimmer locations have been performed in anticipation of the future employment of skimmed, differentially pumped beams. The assembly of a new deposition system supporting two skimmed and differentially pumped supersonic beams and associated in-situ characterization using reflection high energy electron diffraction and on-line x-ray photoelectron spectroscopy has made excellent progress. At Arizona State University, construction of a selected energy epitaxial deposition (SEED) apparatus is still in progress. The supersonic molecular beam source is under construction and the associated gas manifold has been completed. The UHV chambers for the dual Colutron ion-beam system have been completed and are being assembled. Deposition of AlN and GaN films using an effusive source and activated nitrogen species via microwave discharge has been conducted in a test chamber for the purpose of interfacing to the LEEM for in situ real-time observation of film growth. Various schemes of preparing the 6H-SiC(000l) substrates were explored and the resulting surfaces were studied by LEED/LEEM. Removal of the scratches on the SiC substrate surfaces remains a challenging problem.

Descriptors :   *ENERGY, *THIN FILMS, *EPITAXIAL GROWTH, *ELECTRON MICROSCOPY, *DEPOSITION, *LOW ENERGY, *ALUMINUM, *GALLIUM, *SILICON CARBIDES, SOURCES, ACTIVATION, REAL TIME, MICROWAVES, SUBSTRATES, ION BEAMS, MOLECULAR BEAMS, NITRIDES, NITROGEN, GASES, SURFACES, ELECTRON ENERGY, PUMPING(ELECTRONICS), X RAY PHOTOELECTRON SPECTROSCOPY, ONLINE SYSTEMS, SUPERSONIC CHARACTERISTICS, EFFUSION, TEST FACILITIES, CHAMBERS.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Atomic and Molecular Physics and Spectroscopy
      Optics
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE