GaN Rods Grown on Si by SAG-HVPE toward GaN HVPE/InGaN MOVPE Core/Shell Structures

Selective area growth hydride vapor phase epitaxy (SAG-HVPE) and metal organic vapor phase epitaxy (MOVPE) processes are coupled for the synthesis of high quality c-axis InGaN/GaN core/shell structures. The core consists of high aspect ratio GaN rods grown by SAG-HVPE on patterned N-polar AlN on Si(100) substrates. The shell is grown by MOVPE which provides abrupt InGaN/GaN multiquantum wells (MQWs). Microphotoluminescence (μ-PL) analysis performed on the HVPE GaN core exhibit a narrow emission line of 3 meV in line width associated with the neutral-donor bound exciton revealing the excellent optical properties of the GaN material. For the core/shell wire geometry, the silane free HVPE process ensured the whole lateral cladding of the core. The hybrid HVPE core/MOVPE shell structures exhibit high optical quality without yellow luminescence.