Spectroscopic ellipsometry analysis of InGaN/GaN and AlGaN/GaN heterostructures using a parametric dielectric function model
Spectroscopic ellipsometry (SE) has been used for the characterization of AlGaN/GaN and InGaN/GaN heterostructures. The resulting pseudodielectric function spectra were analyzed using a multilayer approach, describing the dielectric functions of the individual layers by a parametric oscillator model. From this analysis, the dielectric function spectra of GaN, Al{sub x}Ga{sub 1{minus}x}N (x {le} 0.16), and In{sub 0.13}Ga{sub 0.87}N were deduced. Further, the dependence of the Al{sub x}Ga{sub 1{minus}x}N band gap energy on the Al mole fraction was derived and compared with photoluminescence data recorded on the same material. The SE band gap data are compatible with a bowing parameter close to 1 eV for the composition dependence of the Al{sub x}Ga{sub 1{minus}x}N gap energy. Finally, the parametric dielectric functions have been used to model the pseudodielectric function spectrum of a complete GaN/AlGaN/InGaN LED structure.
- Research Organization:
- Fraunhofer-Inst. fuer Angewandte Festkoerperphysik, Freiburg (DE)
- OSTI ID:
- 20104621
- Resource Relation:
- Conference: 1999 Materials Research Society Fall Meeting, Boston, MA (US), 11/28/1999--12/03/1999; Other Information: PBD: 2000; Related Information: In: GaN and related alloys -- 1999. Materials Research Society symposium proceedings, Volume 595, by Myers, T.H.; Feenstra, R.M.; Shur, M.S.; Amano, Hiroshi [eds.], [1050] pages.
- Country of Publication:
- United States
- Language:
- English
Similar Records
On the increased efficiency in InGaN-based multiple quantum wells emitting at 530–590 nm with AlGaN interlayers
Collective effects of interface roughness and alloy disorder in In{sub x}Ga{sub 1{minus}x}N/GaN multiple quantum wells