Selected Energy Epitaxial Deposition and Low Energy Electron Microscopy of AlN, GaN and SiC Thin Films.
Abstract
Gallium nitride has been deposited using hyperthermal and thermal beams of NH3 and triethylgallium seeded in He and Ar supersonic jets, respectively. The V/III ratio = 344. The growth rates were lower and the film character poor when Ar was used as the carrier. The films deposited using He were continuous and adherent and exhibited a characteristic wavy surface morphology. The major components of a new SEED facility have been received and verified. In research regarding direct ion beam deposition of GaN, it has been determined that ion current densities for N2(+) at 10 and 20 eV using a Colutron ion beam unit are an order of magnitude higher at the latter energy; the peak current density at 20 eV is approx. 200 nA /sq cm, which corresponds to approx. 10(exp -3) ML/sec deposition rate. The time of flight technique has been employed to characterize the intensity, energy, energy spread, and composition of a 10% NH3 seeded He supersonic beam between 200 and 600 deg C and as a function of stagnation pressure and beam diameter. Clustering played a major role in determining the mean kinetic energy, as well as the energy spread. Initial density-functional calculations focused on the construction of various pseudopotentials for Ga involving the core states have been made to determine a proper treatment of the Ga d shell.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1996
- Accession Number
- ADA307311
Entities
People
- H. Henry Lamb
- I. S. Tsong
- Robert F Davis
Organizations
- North Carolina State University