Growth of Lattice Matched Nitride Alloys and Structures
Abstract
Boron-gallium nitride, boron-aluminum nitride and gallium-aluminum nitride films have been deposited on sapphire substrates by organometallic vapor phase epitaxy and their properties have been investigated by Transmission Electron Microscopy, high resolution x-ray diffraction, and Hall effect. Solid solubility limits of boron in AlN and GaN have been determined to be 1 and 7%, respectively. Growth of B(x)Ga(1-x)N shows severe poisoning effect with growth rates dropping rapidly whenever sp2-bonded BN phase is detected by x-ray diffraction. The quality of B(x)Ga(1-x)N and B(x)Al(1-x)N films degrades with increasing x both in terms of changes of lattice parameter indicating random strains/composition variation and misorientations between low angle grains in the film. The concentration of point defects also increases resulting in increase of electron concentration at low x and deep center concentration at x > 0.20. n-type doping of films with silicon allowed to achieve electron concentration in 10 to the 18th power per cu cm range for x up to 0.55. For higher aluminum content silicon donors exhibit DX-like behavior.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 22, 1998
- Accession Number
- ADA354115
Entities
People
- D. W. Greve
- Marek Skowronski
Organizations
- Carnegie Mellon University