A study was made of semi-polar (11•1) InGaN-based light-emitting diodes grown on patterned (001) Si substrates by atmospheric-pressure metal organic chemical vapour deposition. A transmission electron microscopy image of the semi-polar template showed that the threading dislocation density was decreased significantly. From electroluminescence measurement, semi-polar light-emitting diodes exhibit little blue-shift and low efficiency droop at a high injection current because the reduction of the polarization field not only made the band diagram smoother but also restricted electron overflow to the p-GaN layer as shown in simulations. These results indicated that semi-polar InGaN-based light-emitting diodes could possess a high radiative recombination rate and low efficiency droop at a high injection current.

Reduction of Efficiency Droop in Semipolar (1101) InGaN/GaN Light Emitting Diodes Grown on Patterned Silicon Substrates. C.H.Chiu, D.W.Lin, C.C.Lin, Z.Y.Li, W.T.Chang, H.W.Hsu, H.C.Kuo, T.C.Lu, S.C.Wang, W.T.Liao, T.Tanikawa, Y.Honda, M.Yamaguchi, N.Sawaki: Applied Physics Express, 2011, 4[1], 012105