Growth and characterization of crack-free semipolar {1-101}InGaN/GaN multiple-quantum well on V-grooved (001)Si substrates

This work elucidates the two-stage growth of GaN on V-grooved (001)Si substrates using metal-organic chemical vapor deposition. The first growth stage proceeds on the {111}Si sidewalls until GaN fills the V grooves. Then the second stage continues and leads to a semipolar surface with the {1-101}GaN facets. GaN films with thickness of over 1 mu m can be obtained without cracks by this two stage-growth. Excitation-power-dependent and time-resolved photoluminescence measurements confirm that the internal electric field in the InGaN/GaN multiple-quantum well (MQW) grown on this GaN template is indeed smaller than that of the MQW grown on (0001)GaN. (C) 2008 American Institute of Physics.