PHOTOLUMINESCENCE STUDIES OF GaN AND AlGaN LAYERS UNDER HYDROSTATIC PRESSURE
نویسندگان
چکیده
Wide bandgap GaN very often shows a high electron concentration. Although several impurities such as O and Si have been identified, the concentration is not high enough to account for the number of free carriers. As a consequence native defects namely the nitrogen vacancies are widely considered to be present at high densities. Several calculations predict different energy levels of this strongly localized defect. We present photoluminescence experiments of wurtzite GaN and AlGaN layers under large hydrostatic pressure to search for localized defects within the questionable energy range of 3.0 to 3.8 eV above the valence band edge.
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