Doping Mechanisms in Wide Bandgap Group III Nitrides
Abstract
The role of charge transfer and Fermi level position on impurity solubility, native defect formation and stability in GaN semiconductors was investigated. Several issues were addressed that include: (1) the structure, identity, solubility and stability of intentionally added and unintentional compensating donor defects in p-type and its material, (2) the role hydrogen complexes play in compensating p-type layers, and (3) the role oxygen and Si play in formation of defect complexes with Mg in GaN. The main objective was to determine the factors, which limit p-type conductivity in GaN and its alloys and to develop doping techniques to increase the hole concentrations to greater than 10(exp 19)/cu cm. The concentrations of both native defects and impurities were measured and its dependence on Fermi level determined. From the measured defect concentrations, the formation energies were calculated and compared to recent first principles, total-energy calculations for both native defects and impurities.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 18, 2002
- Accession Number
- ADA404872
Entities
People
- Bruce W Wessels
Organizations
- Northwestern University