Growth of wurtzite InN using MOVPE and its optical characteristics

The phase diagram for wurtzite InN epitaxial growth using metalorganic vapor phase epitaxy was established. InN films grown under optimized conditions had high quality, as confirmed by confocal micro-Raman scattering, X-ray diffraction, and reflection high-energy-electron diffraction. InN showed a band-gap energy Eg of 0.8 to 1.0 eV and 0.7 to 0.8 eV as measured by optical absorption and photoluminescence, respectively. From the band-gap bowing of InGaN and the relationship between the band gap and bond length, Eg of InN seems to be near 0.8 eV. This value is less than half the value reported using polycrystals up to the 1990s. The temperature dependence of Eg is very small and this temperature stability will of great advantage to devices. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)