Accession Number:

ADA248993

Title:

Growth, Characterization and Device Development in Monocrystalline Diamond Films

Descriptive Note:

Quarterly letter rept. 1 Jan-31 Mar 1992,

Corporate Author:

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

Personal Author(s):

Report Date:

1992-03-01

Pagination or Media Count:

33.0

Abstract:

The effects of hydrogen on cluster binding energy and growth mode of diamond, the determination of the Schottky barrier height for Ti on 111 diamond and models for MESFET devices in diamond have been the subjects addressed in this reporting period. Capillarity and atomistic formulations for determining diamond thin film growth modes have been compared. Arguments are presented based on simple atomistic cluster binding energy calculations that suggest hydrogen should play an important role in stabilizing the 2-dimensional cluster configuration and thus promote layered diamond growth, assuming that the interfacial strain and misfit energies are not too high. Assumptions which may cause this model to break down experimentally are also discussed. The Ti-natural IIB111 diamond interface has been investigated using UV photo-emission produced by a 21.2 eV light source. The chemically cleaned diamond showed a sharp 0.5 eV FWHM peak at the position of the conduction band indicating a negative electron affinity surface. By determining the relative positions of the diamond valence band edge and the titanium Fermi level, the Schottky barrier height of titanium on diamond 111 was measured and found to be 1.0 or - 0.2 eV. A model for the observed titanium induced negative electron affinity is proposed, based on the Schottky barrier height of titanium on diamond, and the work function of titanium. A detailed, theoretical model for p-type diamond MESFETs is being developed.

Subject Categories:

  • Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE