Patent ID: 8591652

Claim:
Process for the manufacture of a semiconductor substrate, comprising the following process steps: a) providing a starting substrate, b) forming a mask layer with a multitude of concave openings on the starting substrate, wherein the mask layer is structured, either lithographically by opening windows through a wet- or dry-chemical etching process, or through a lift-off process, c) growing at least one semiconductor substrate vertically out of said concave openings obtained in step b), wherein the mask layer is laterally overgrown by at least one semiconductor material which completely covers, in contact, the mask material and whereby the growth fronts coalesce, and subsequently, d) cooling of starting substrate, mask layer and semiconductor substrate, wherein the material for forming the mask layer comprising at least partially of tungsten silicide nitride, and wherein a separation of semiconductor substrate and starting substrate occurs during the growth or during the cooling, and wherein a semiconductor substrate is obtained free-standing, wherein the semiconductor substrate contains at least a nitride compound semiconductor.