Coincident site lattice-matched InGaN on (111) spinel substrates

Coincident site lattice-matched wurtzite (0001) In0.31Ga0.69N, emitting in the important green wavelength region, is demonstrated by molecular beam epitaxy on a cubic (111) MgAl2O4 spinel substrate. The coincident site lattice matching condition involves a 30 degrees rotation between the lattice of the InGaN epitaxial layer and the lattice of the spinel. This work describes an alternative approach towards realizing more compositionally homogenous InGaN films with low dislocation density emitting in the "green gap" of low efficiency currently observed for semiconductor light emitting diodes (LEDs). This approach could lead to higher efficiency green LEDs presently of great interest for solid-state lighting applications. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3702577]