A method of forming a semiconductor device having customized contacts, the method comprising: providing a first insulator layer; patterning the first insulator layer such that the first insulator layer defines at least one contact window; providing a second insulator layer (435, 436) on the first insulator layer and in the at least one contact window such that the second insulator layer (435, 436) at least partially fills the at least one contact window, the second insulator layer (435, 436) including at least two insulator sub-layers (435, 436), a first sub-layer of the second insulator layer on the first insulator layer and in the at least one contact window and a second sub-layer of the second insulator layer in the at least one contact window on the first sub-layer of the second insulator layer; and etching a first portion of the first and second sub-layers of the second insulator layer such that second portions (435', 436') of the second insulator layer remain in the at least one contact window to provide at least one modified contact window having dimensions that are smaller than dimensions of the at least one contact window; wherein providing the first insulator layer is preceded by providing a wide bandgap semiconductor layer, wherein providing the first insulator layer comprises providing the first insulator layer on the wide bandgap semiconductor layer and wherein patterning the first insulator layer is to expose a portion of a surface of the wide bandgap semiconductor layer through the at least one contact window in the first insulator layer and wherein the first sub-layer of the second insulator layer has a first etch rate for said etching associated therewith and wherein the second sub-layer of the second insulator layer has a second etch rate for said etching associated therewith, the second etch rate being different than the first etch rate; and wherein the wide bandgap semiconductor layer comprises gallium nitride, GaN, and/or silicon carbide, SiC. providing a first insulator layer; patterning the first insulator layer such that the first insulator layer defines at least one contact window; providing a second insulator layer (435, 436) on the first insulator layer and in the at least one contact window such that the second insulator layer (435, 436) at least partially fills the at least one contact window, the second insulator layer (435, 436) including at least two insulator sub-layers (435, 436), a first sub-layer of the second insulator layer on the first insulator layer and in the at least one contact window and a second sub-layer of the second insulator layer in the at least one contact window on the first sub-layer of the second insulator layer; and etching a first portion of the first and second sub-layers of the second insulator layer such that second portions (435', 436') of the second insulator layer remain in the at least one contact window to provide at least one modified contact window having dimensions that are smaller than dimensions of the at least one contact window; wherein providing the first insulator layer is preceded by providing a wide bandgap semiconductor layer, wherein providing the first insulator layer comprises providing the first insulator layer on the wide bandgap semiconductor layer and wherein patterning the first insulator layer is to expose a portion of a surface of the wide bandgap semiconductor layer through the at least one contact window in the first insulator layer and wherein the first sub-layer of the second insulator layer has a first etch rate for said etching associated therewith and wherein the second sub-layer of the second insulator layer has a second etch rate for said etching associated therewith, the second etch rate being different than the first etch rate; and wherein the wide bandgap semiconductor layer comprises gallium nitride, GaN, and/or silicon carbide, SiC.