A method for obtaining a plurality of mesas (550A, 550B), each mesa (550A, 550B) being at least partly made of a nitride preferably obtained from at least one of gallium (Ga), indium (In) and aluminium (Al), the method comprising the following successive steps: - providing a stack comprising a substrate and at least the following layers successively arranged from the substrate: o a first layer, referred to as the creep layer, made of a material having a glass transition temperature, the creep layer having a glass transition temperature T glass transition, o a second, crystalline layer, referred to as the crystalline layer, different from the creep layer, - forming pads (1000A1-1000B4) by etching at least the crystalline layer and at least one portion of the creep layer so that: o each pad (1000A1-1000B4) includes at least: - a first section, referred to as the creep section (220A1-220B4), formed by at least one portion of the creep layer, - a second, crystalline section, referred to as the crystalline section (300A1, 300B4), formed by the crystalline layer and being above the creep section (220A1-220B4), o the pads (1000A1-1000B4) are distributed over the substrate so as to form a plurality of sets (1000A, 1000B) of pads (1000A1-1000B4), - epitaxially growing a crystallite (510A1-510B4) on at least some of said pads (1000A1-1000B4) and continuing epitaxially growing the crystallites (510A1-510B4) until the crystallites (510A1-510B4) carried by the adjacent pads (1000A1-1000B4) of a same set (1000A, 1000B) coalesce, so as to form a nitride mesa (550A, 550B) on each set (1000A, 1000B), epitaxially growing being carried out at a temperature T epitaxy, such that: T epitaxy ≥ k 1 × T glass transition, with k 1 ≥ 0.8 - stopping epitaxially growing the crystallites (510A1-510B4) before crystallites (510A1-510B4) belonging to two distinct sets (1000A, 1000B) begin to coalesce, so that the mesas (550A, 550B) of each set (1000A, 1000B) are spaced apart from each other. - providing a stack comprising a substrate and at least the following layers successively arranged from the substrate: o a first layer, referred to as the creep layer, made of a material having a glass transition temperature, the creep layer having a glass transition temperature T glass transition, o a second, crystalline layer, referred to as the crystalline layer, different from the creep layer, o a first layer, referred to as the creep layer, made of a material having a glass transition temperature, the creep layer having a glass transition temperature T glass transition, o a second, crystalline layer, referred to as the crystalline layer, different from the creep layer, - forming pads (1000A1-1000B4) by etching at least the crystalline layer and at least one portion of the creep layer so that: o each pad (1000A1-1000B4) includes at least: - a first section, referred to as the creep section (220A1-220B4), formed by at least one portion of the creep layer, - a second, crystalline section, referred to as the crystalline section (300A1, 300B4), formed by the crystalline layer and being above the creep section (220A1-220B4), o the pads (1000A1-1000B4) are distributed over the substrate so as to form a plurality of sets (1000A, 1000B) of pads (1000A1-1000B4), o each pad (1000A1-1000B4) includes at least: - a first section, referred to as the creep section (220A1-220B4), formed by at least one portion of the creep layer, - a second, crystalline section, referred to as the crystalline section (300A1, 300B4), formed by the crystalline layer and being above the creep section (220A1-220B4), - a first section, referred to as the creep section (220A1-220B4), formed by at least one portion of the creep layer, - a second, crystalline section, referred to as the crystalline section (300A1, 300B4), formed by the crystalline layer and being above the creep section (220A1-220B4), o the pads (1000A1-1000B4) are distributed over the substrate so as to form a plurality of sets (1000A, 1000B) of pads (1000A1-1000B4), - epitaxially growing a crystallite (510A1-510B4) on at least some of said pads (1000A1-1000B4) and continuing epitaxially growing the crystallites (510A1-510B4) until the crystallites (510A1-510B4) carried by the adjacent pads (1000A1-1000B4) of a same set (1000A, 1000B) coalesce, so as to form a nitride mesa (550A, 550B) on each set (1000A, 1000B), epitaxially growing being carried out at a temperature T epitaxy, such that: T epitaxy ≥ k 1 × T glass transition, with k 1 ≥ 0.8 - stopping epitaxially growing the crystallites (510A1-510B4) before crystallites (510A1-510B4) belonging to two distinct sets (1000A, 1000B) begin to coalesce, so that the mesas (550A, 550B) of each set (1000A, 1000B) are spaced apart from each other.