Low Temperature Deposition and Characterization of N- and P-Type Silicon Carbide Thin Films and Associated Ohmic and Schottky Contacts
Abstract
The cleaning and etching of the vicinal alpha (6H)-SiC(0001) surface has been emphasized in this reporting period because of its recently demonstrated importance in the MBE of SiC and AlN films on SiC wafers and layers. Etching with a solution of 1:1:10HF:H2: ethanol and a hydrogen plasma sharply reduced both the oxide and the C surface concentrations as determined by AES and XPS spectra. Controlled growth of both Beta-SiC and alpha (6H)-SiC films have been achieved on SiC wafers and films. Flow ratios of C2H4 and Si2H6 of 1:1 result in 6H-SiC while C-rich ratios give 3C-SiC. Surface reconstruction as a function of surface treatment have also been related to the deposited SiC polytype. The initial stages of AlN film growth has also been investigated in terms of defects via TEM. Two types of defects were found in the AlN film: one caused by lattice mismatch; the other by the presence of steps in the SiC surface. The interfacial chemistry and microstructure, electrical properties and the Schottky barrier heights of thin films on Alpha (6H)-SiC(0001) surfaces were investigated after annealing to 700 deg C and a maximum time of 60 min. The reaction zone contained Ti5Si3 and TiC. The electrical properties changed little as a function of heat treatment.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1993
- Accession Number
- ADA274345
Entities
People
- Lisa M. Porter
- M. C. Benjamin
- Robert F Davis
- Robert J. Nemanich
- S. Kern
Organizations
- North Carolina State University