6533b839fe1ef96bd12a672b
RESEARCH PRODUCT
Optical characterization of Mg-doped GaN films grown by metalorganic chemical vapor phase deposition
Oliver AmbacherMartin StutzmannAndrés CantareroGema Martínez-criadoRoman DimitrovAna Crossubject
PhotoluminescenceMaterials scienceIII-V semiconductorsScanning electron microscopeAnalytical chemistryGeneral Physics and AstronomySemiconductor thin filmsChemical vapor depositionStacking faultsSurface topographysymbols.namesake:FÍSICA [UNESCO]MagnesiumGallium compounds ; III-V semiconductors ; Wide band gap semiconductors ; Magnesium ; Semiconductor thin films ; MOCVD coatings ; Scanning electron microscopy ; Raman spectra ; Photoluminescence ; Surface composition ; Surface topography ; Stacking faults ; Inclusions ; ExcitonsPhotoluminescenceWurtzite crystal structureDopingUNESCO::FÍSICAGallium compoundsWide band gap semiconductorsMOCVD coatingsSurface compositionInclusionssymbolsSapphireExcitonsRaman spectraRaman spectroscopyScanning electron microscopyStacking faultdescription
Scanning electron microscopy, micro-Raman, and photoluminescence (PL) measurements are reported for Mg-doped GaN films grown on (0001) sapphire substrates by low-pressure metalorganic chemical vapor phase deposition. The surface morphology, structural, and optical properties of GaN samples with Mg concentrations ranging from 1019 to 1021 cm−3 have been studied. In the scanning micrographs large triangular pyramids are observed, probably due to stacking fault formation and three-dimensional growth. The density and size of these structures increase with the amount of magnesium incorporated in the samples. In the photoluminescence spectra, intense lines were found at 3.36 and 3.31 eV on the triangular regions, where the presence of cubic inclusions was confirmed by micro-Raman measurements. The excitation dependence and temperature behavior of these lines enable us to identify their excitonic nature. From our study we conclude that the interface region between these defects and the surrounding wurtzite GaN could be responsible for PL lines. Ana.Cros@uv.es ; cantarer@uv.es ; Gema.Martinez@uv.es
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2000-09-15 |