Epitaxial methods and templates grown by the methods

A method for fabricating a layer comprising a group III nitride semiconductor material, the method comprising:

• providing a substrate comprising a plurality of islands separated in a substantially random spatial arrangement forming an irregular pattern, with the islands having upper portions with one or more selected crystal properties, and further comprising a material on which the semiconductor material preferentially nucleates and grows;
• depositing a masking material on the substrate to cover the islands and spaces therebetween;
• removing part of the masking material and islands to provide a substantially planar surface having upper portions of a majority of the islands exposed surrounded by masking material;
• and
• growing the semiconductor material on the substrate under conditions selected first to favor nucleation, then to favor more vertical growth of the layer material from the upper portions on the islands, then epitaxial lateral overgrowth (ELO) laterally beyond the islands from the more-vertically-grown layer material, and then coalescence to form a substantially continuous and monocrystalline final semiconductor layer that inherits one or more of the selected crystal properties.