Mechanistic Studies of Opto-Electronic Materials and Syntheses Using Multiple Laser and Surface Diagnostics
Abstract
The objective of this program was the development of novel OMCVD/LCVD processes for preparation of wide band-gap semiconductors and the elucidation of the basic reaction mechanisms in these processes, so as to control the deposition rates and to improve the opto-electronic properties of the materials. The synthesis and the mechanistic elucidation of wide band-gap III/V metal nitrides by OMCVD and LCVD, the dry-passivation of GaAs and the deposition of carbon nitride films, have been carried out with a unique UHV surface reaction system equipped with multiple gas-phase and surface species analyses. The system was constructed with joint support from the ONR and Emory University. Gas-phase species were detected by EI- and REMPI-MS, whereas surface species and structure were characterized by multiple surface diagnostic tools: AES, UPS, XPS, LEED, SEM and HREELS. The systematic elucidation of the spectroscopy and the mechanisms for the thermal and photochemical decomposition reactions of individual source molecules involved in the OMCVD/LCVD processes were first carried out before the actual deposition processes were conducted. We used a new nitrogen source, hydrazoic acid (HN3), for the preparation of InN films with 1:1 elemental ratio by low-pressure CVD. The prepared films were characterized by AES, UPS, XPS, SEM, LEED and HREELS, and optical techniques such as UV/visible adsorption and photo-luminescence. InN films with very high quality SEM and UPS characteristics have been deposited on GaAs substrates without a buffer layer. Over 20 technical papers (with 23 presentations) were completed from these studies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 31, 1993
- Accession Number
- ADA274528
Entities
People
- Lin Ming-chang
Organizations
- Emory University