Patent ID: 7960255

Claim:
Process for forming a wire portion in an integrated electronic circuit, comprising the following steps: /1/ providing a substrate from which the circuit is to be produced, which substrate comprises a layer stack including a layer portion of seed material and two layer portions of passive materials located on respective opposite faces of said layer portion of seed material, so that a crystalline part of the layer portion of seed material is exposed at a side surface of the stack between boundaries with said passive materials; /2/ growing epitaxially a wire material on the seed material exposed at the side surface of the stack, said growing being selective with respect to the passive materials so as to form the wire portion extending on and along the exposed crystalline part of the layer portion of seed material, the wire material and the seed material having respective different chemical compositions; and /3/ removing the layer portion of seed material selectively with respect to the wire material while retaining fixedly the wire portion on the circuit substrate, wherein the crystalline part of the layer portion of seed material exposed at the side surface of the stack has a varying thickness between the boundaries with said passive materials, measured parallel to a stacking direction of the layer stack at different locations in said exposed crystalline part of the layer portion of seed material.