It was recalled that the growth of InGaN/GaN light-emitting devices on non-polar or semi-polar planes offered a viable approach to reducing or eliminating problems associated with polarization-related electric fields present in c-plane III-nitride heterostructures. Important issues were the origin of the pyramidal hillocks typically observed on nominally on-axis m-plane GaN films, the effects of m-plane substrate misorientation on surface morphology and device performance, the mechanics of anisotropic cracking in tensile strained m-plane AlGaN films, the formation of basal-plane stacking faults in long-wavelength m-plane InGaN quantum wells, and the mechanisms for stress relaxation in semi-polar AlGaN and InGaN films. Here, the materials and growth issues unique to high-performance non-polar and semi-polar light-emitting devices grown on high-quality free-standing GaN substrates were reviewed.

Materials and Growth Issues for High-Performance Nonpolar and Semipolar Light-Emitting Devices. R.M.Farrell, E.C.Young, F.Wu, S.P.DenBaars, J.S.Speck: Semiconductor Science and Technology, 2012, 27[2], 024001