Superatmospheric MOCVD Growth of Bulk InGaN for Template and Optoelectronic Applications

Abstract

InGaN, a III-Nitride semiconductor, has bandgaps between 0.7 eV (InN) and 3.39 eV (GaN), covering the entire visible spectrum, which makes InGaN an important material for photonic applications. To utilize the full range of InGaN’s bandgap, methods for material growth with increased indium content must be established. MOCVD synthesis of InGaN with indium content higher than approximately 20% has been difficult to achieve while maintaining high crystal quality. There is evidence that superatmospheric MOCVD growth can establish such a method. Work by Cheng Li et. al. indicates that the photoluminescent intensity increases with pressure, while thermodynamics indicate favorable conditions for superatmospheric growth. Growths of GaN and InGaN were done at 1.5 bar-a, with promising results. GaN was successfully grown with low yellow band luminescence and high indium composition material was grown, confirmed by X-Ray diffraction. The possibility of superatmospheric growth of high indium content InGaN was confirmed.