Strain effects on excitonic transitions in GaN
- Oklahoma State Univ., Stillwater, OK (United States). Center for Laser and Photonics Research
- North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering
- Honeywell Technology Center, Plymouth, MN (United States)
The authors present the results of experimental studies of the strain effects on the excitonic transitions in GaN epitaxial layers on sapphire and SiC substrates. Photoluminescence and reflectance spectroscopies were performed to measure the energy positions of exciton transitions and X-ray diffraction measurements were conducted to examine the lattice parameters of GaN epitaxial layers grown on different substrates. Residual strain induced by the mismatch of lattice constants and thermal-expansion between GaN epitaxial layers and substrates was found to have a strong influence in determining the energies of excitonic transitions. The overall effects of the strain generated in GaN is compressive for GaN grown on sapphire and tensile for GaN on SiC substrate. The uniaxial and hydrostatic deformation potentials of wurtzite GaN were derived from the experimental results. The results yield the uniaxial deformation potentials b{sub 1} {approx} {minus}5.3 eV and b{sub 2} {approx} 2.7 eV, as well as the hydrostatic components a{sub 1} {approx} {minus}6.5 eV and a{sub 2} {approx} {minus}11.8 eV.
- Sponsoring Organization:
- Defense Advanced Research Projects Agency, Arlington, VA (United States); Office of Naval Research, Washington, DC (United States)
- OSTI ID:
- 585835
- Report Number(s):
- CONF-961202-; ISBN 1-55899-353-3; TRN: IM9810%%57
- Resource Relation:
- Conference: 1996 Fall meeting of the Materials Research Society (MRS), Boston, MA (United States), 2-6 Dec 1996; Other Information: PBD: 1997; Related Information: Is Part Of III-V nitrides; Ponce, F.A. [ed.] [Xerox Palo Alto Research Center, CA (United States)]; Moustakas, T.D. [ed.] [Boston Univ., MA (United States)]; Akasaki, I. [ed.] [Meijo Univ., Nagoya (Japan)]; Monemar, B.A. [ed.] [Linkoeping Univ. (Sweden)]; PB: 1278 p.; Materials Research Society symposium proceedings, Volume 449
- Country of Publication:
- United States
- Language:
- English
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