Accession Number:

ADA256283

Title:

Growth, Characterization and Device Development in Monocrystalline Diamond Films

Descriptive Note:

Quarterly letter rept. 1 Jul-30 Sep 1992

Corporate Author:

NORTH CAROLINA STATE UNIV AT RALEIGH

Personal Author(s):

Report Date:

1992-09-01

Pagination or Media Count:

72.0

Abstract:

Ordered diamond films have been deposited on single crystal Si100 substrates via in-situ carburization followed by bias-enhanced nucleation. Photoluminescence and Raman spectroscopy have been employed to determine the time evolution of defect formation in these CVD diamond films for stages of growth spanning nucleation to continuous film formation. Analysis of the 1332cm. diamond feature showed two rates of diamond growth with a transition at the thickness where nearly complete coverage was obtained. Investigation of the various defects in the films led to the conclusions that Si atoms most likely caused the 1.68 eV optical centers at the initial stages of growth. Luminescence associated with sp squared bonding defects appeared only after a continuous film was formed. The CVD growth of diamond films on Si 100 have also been studied using scanning tunneling spectroscopy. The surface of the diamond film possessed electronic structure similar to single crystal diamond. By contrast the initial growth surface showed evidence of Beta-SiC and graphite electronic structures. The microwave performance of p-type diamond MESFETs is also under investigation. The surface breakdown model has been further refined and an activation model has been included so that free charge density as a function of temperature could be determined. Research is also underway to simulate the performance of the Kobe p- channel MESFET. A pn junction gate model is also being formulated so that the operation of a diamond JFET can be investigated. Diamond thin films, Silicon carbide, Heteroepitaxial nucleation, Misfit dislocations, Interfacial strain energy, Plasma cleaning, Negative electron affinity, Atomic hydrogen, Argon plasma, UV photoemission.

Subject Categories:

  • Electrical and Electronic Equipment
  • Crystallography
  • Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE