A method of fabricating micro-chips, including: (a) providing a substrate; (b) forming a first single-crystal layer on a top surface of the substrate; (c) forming a second single-crystal layer on a top surface of the first single-crystal layer; (d) forming integrated circuits in the second single-crystal layer; (e) forming a set of intersecting trenches in the second-single crystal layer to form single-crystal islands, each single-crystal island containing one or more of the integrated circuits, the first single-crystal layer exposed in a bottom of the trench; and (f) removing the first single-crystal layer in order to separate the single-crystal islands from the substrate.