Infrared reflection of GaN and AlGaN thin film heterostructures with AlN buffer layers

Journal Article · Sun Mar 31 23:00:00 EST 1996 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.116179· OSTI ID:283785

Wetzel, C; Haller, E E ^[1]; Amano, H; Akasaki, I ^[2]

---

1. Lawrence Berkeley Laboratory and University of California, Berkeley, California 94720 (United States)
2. Department of Electrical and Electronic Engineering, Meijo University, Nagoya (Japan)

Infrared reflection spectroscopy is applied to state-of-the-art thin film heterostructures of group-III nitrides on sapphire and Si substrates. The individual layers of GaN and AlGaN and the AlN buffer layer are identified by their phonon frequencies. Under non-perpendicular incidence of the light, A{sub 1}(LO) phonon modes are observed in the wurtzite system. The presence of the very thin AlN buffer layer manifests itself in clear features of the AlN phonons. The A{sub 1}(LO) phonon mode energy is determined in Al{sub {ital x}}Ga{sub 1{minus}{ital x}}N for {ital x}{approx_equal}0.15. Raman spectra confirm our findings. {copyright} {ital 1996 American Institute of Physics.}

• Research Organization: Lawrence Berkeley National Laboratory
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 283785
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 18 Vol. 68; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM NITRIDES
GALLIUM NITRIDES
INFRARED SPECTRA
PHONONS
RAMAN SPECTRA
REFLECTION SPECTROSCOPY
REFLECTIVITY
SPECTROSCOPY
THIN FILMS