Abstract: A method for obtaining mesas that are made at least in part of a nitride (N), the method includes providing a stack comprising a substrate and at least the following layers disposed in succession from the substrate a first layer, referred to as the flow layer, and a second, crystalline layer, referred to as the crystalline layer; forming pads by etching the crystalline layer and at least one portion of the flow layer such that: —each pad includes at least: —a first section, referred to as the flow section, formed by at least one portion of the flow layer, and a second, crystalline section, referred to as the crystalline section, framed by the crystalline layer and overlying the flow section, the pads are distributed over the substrate so as to form a plurality of sets of pads; and epitaxially growing a crystallite on at least some of said pads and continuing the epitaxial growth of the crystallites until the crystallites carried by the adjacent pads of the same set coalesce.

Abstract: A process for obtaining a nitride (N) layer preferably obtained from at least one of gallium (Ga), indium (In) and aluminium (Al), may include: on a stack including a substrate and at least the following layers successively disposed from the substrate: a creep layer having a glass transition temperature, Tglass transition, and a crystalline layer, forming pads by etching the stack so that each pad includes at least a creep segment formed by at least a portion of the creep layer, and a crystalline segment formed by the crystalline layer; and growing by epitaxy a crystallite on each of the pads and continuing the epitaxial growth of the crystallites so as to form the nitride layer. The epitaxial growth may be carried out at a temperature Tepitaxy, such that Tepitaxy?k1×Tglass transition, with k1 being 0.8.