Growth, Characterization and Device Development in Monocrystalline Diamond Films
Abstract
Two chemical vapor deposition (CVD) systems (hot filament and microwave plasma) and a multitechnique analysis system have been designed, constructed and characterized. The effects of surface steps, substrate material and substrate/filament bias have been examined. Diamond films from outside sources have been analyzed by a variety of techniques. Most notably, numerous defects, especially (111) twins, have been identified by TEM and are similar to those found in natural diamond. Certain diamond particles were in a twinned epitaxial relationship with the Silicon substrate. It has also been found that a thin Silicon carbide layer forms immediately (i.e. <5 min) upon exposure to the Methane + Hydrogen plasma, followed by the slow formation of the diamond crystallites. Large-Signal, nonlinear device models for both microwave diamond power MESFETs and mm-wave diamond IMPATT diodes have been developed. Diamond power MESFETs operating in X-band are found to be capable of producing approximately 25 W/unit gate width of RF power with a power-added efficiency of greater than 40%. A diamond IMPATT oscillator should produce about 2 W RF power with an efficiency of 10% at 100 GHz. Keywords: Thin films.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1990
- Accession Number
- ADA218211
Entities
People
- J. T. Glass
- K. J. Bachmann
- R. J. Trew
- Robert F Davis
- Robert J. Nemanich
Organizations
- North Carolina State University