Abstract: Group II-nitride heterostructures that include an In-containing group III-nitride alloy with a high crystal quality for use as buffer layers in light-emitting devices are provided. Also provided are light-emitting devices, such as light-emitting diodes and laser diodes, that incorporate the heterostructures and metal-organic chemical vapor deposition (MOCVD) methods for growing the heterostructures. The heterostructures include a substrate, a thin nucleation layer of an In-containing group III-nitride, a thin cap layer on the nucleation layer, and an In-containing group II-nitride alloy overlayer on the cap layer.

Abstract: Pseudo-substrates for the growth of metal nitride alloys are provided. The alloys are incorporated into heterostructures that include at least one porosified layer, a planarizing coalescence layer on the at least one porosified layer, and a terminal layer that includes or consists of a layer of at-least-partially strain-relaxed, non-porous metal nitride alloy. The pseudo-substrates are grown epitaxially and porosified via thermal decomposition in situ without the need for a decomposition stop layer.