A method of forming a structure comprising an indium gallium nitride (InGaN) layer, the method comprising: growing an InGaN layer, comprising: growing a first InGaN sublayer using a first set of growth conditions, and growing at least one second InGaN sublayer over the first InGaN sublayer using a second set of growth conditions different from the first set of growth conditions, the first InGaN sublayer and the at least one second InGaN sublayer forming the InGaN layer, forming the InGaN layer to have an average total thickness (D 0) greater than a critical thickness (D C1) of the first InGaN sublayer and less than a critical thickness (D C2) of the second InGaN sublayer, wherein the critical thickness of each InGaN sublayer is the average total thickness of said sublayer at which and beyond which pseudomorphic growth discontinues and said sublayer undergoes strain relaxation, and selecting the first set of growth conditions and the second set of growth conditions such that a net rate of incorporation of indium into a growth surface of the first InGaN sublayer is at least substantially equal to a net rate of incorporation of indium into a growth surface of the at least one second InGaN sublayer such that a composition of the InGaN layer is constant across the average total thickness of the InGaN layer, wherein selecting the first set of growth conditions and the second set of growth conditions further comprises reducing an incoming flux of indium into the growth surface of the at least one second InGaN sublayer relative to an incoming flux of indium into the growth surface of the first InGaN sublayer, including at least one of decreasing a partial pressure of an indium precursor, reducing a reactor pressure, reducing a precursor flow rate, reducing a ration of the indium precursor to an alkyl, increasing a nitrogen precursor rate and increasing an inert gas flow rate. growing an InGaN layer, comprising: growing a first InGaN sublayer using a first set of growth conditions, and growing at least one second InGaN sublayer over the first InGaN sublayer using a second set of growth conditions different from the first set of growth conditions, the first InGaN sublayer and the at least one second InGaN sublayer forming the InGaN layer, growing a first InGaN sublayer using a first set of growth conditions, and growing at least one second InGaN sublayer over the first InGaN sublayer using a second set of growth conditions different from the first set of growth conditions, the first InGaN sublayer and the at least one second InGaN sublayer forming the InGaN layer, forming the InGaN layer to have an average total thickness (D 0) greater than a critical thickness (D C1) of the first InGaN sublayer and less than a critical thickness (D C2) of the second InGaN sublayer, wherein the critical thickness of each InGaN sublayer is the average total thickness of said sublayer at which and beyond which pseudomorphic growth discontinues and said sublayer undergoes strain relaxation, and selecting the first set of growth conditions and the second set of growth conditions such that a net rate of incorporation of indium into a growth surface of the first InGaN sublayer is at least substantially equal to a net rate of incorporation of indium into a growth surface of the at least one second InGaN sublayer such that a composition of the InGaN layer is constant across the average total thickness of the InGaN layer, wherein selecting the first set of growth conditions and the second set of growth conditions further comprises reducing an incoming flux of indium into the growth surface of the at least one second InGaN sublayer relative to an incoming flux of indium into the growth surface of the first InGaN sublayer, including at least one of decreasing a partial pressure of an indium precursor, reducing a reactor pressure, reducing a precursor flow rate, reducing a ration of the indium precursor to an alkyl, increasing a nitrogen precursor rate and increasing an inert gas flow rate.