Fundamental Studies and Device Development in Beta Silicon Carbide
Abstract
High purity monocrystalline Beta-Silicon Carbide films have been chemically vapor deposited on Si(100) and alpha-SiC(001) at 1660K-1823K and 0.1 MPa using Silane and Ethylene carried in Hydrogen. Films grown on the on-axis Si(100) contained substantial concentrations of dislocations, stacking faults and antiphase boundaries; those deposited on alpha-SiC(0001) contained primarily double positioning boundaries. These boundaries were eliminated by using off-axis orientations of the respective substrates. Films produced on Si(100) have also been doped during growth and via ion implantation with Boron or Aluminum (p-type) or Phosphorus or Nitrogen(n-type) at liquid nitrogen, room and elevated temperatures. Results from the former procedure showed the ionized dopant/total dopant concentration ratios for N, P, B, and AL. The solubility limits of N, P and B at 1660K were determined. High temperature ion implantation coupled with dynamic and post annealing resulted in a markedly reduced defect and precipitate concentration relative to that observed in similar research at the lower temperatures. Dry etching in Carbon Tetrafluoride and Nitrogentrifluoride by reactive ion etching (RIE) and in Sulfur Hexafluoride by plasma etching have also been conducted. Device-compatible surface impurity chemistry and morphology were only obtained using RIE and NF3 combined with a C cathode. Schottky diode, p-n junctions, MESFET and MOSFET devices have been fabricated. The p-n junctions have the characteristics of insulators containing injected carriers. Keywords: Current voltage measurement, Transconductance, Ohmic contacts.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 30, 1988
- Accession Number
- ADA197843
Entities
People
- Robert F Davis
Organizations
- North Carolina State University