Patent ID: 8623669

Claim:
A method of fabricating epitaxial semiconductor devices, comprising: (a) forming an etch limiting film that includes a sacrificial layer on an epitaxial substrate; (b) growing epitaxially layers of a semiconductor structure on the sacrificial layer; (c) forming on the semiconductor structure a layer of a device substrate that can be magnetized, and a patterned passage unit that extends from the device substrate to a depth as deep as the sacrificial layer such that a plurality of semiconductor units are defined in the semiconductor structure and the device substrate; and (d) separating the semiconductor units from the epitaxial substrate by etching laterally the sacrificial layer through the patterned passage unit while a magnetic attraction force is applied to the device substrate, wherein the etch limiting film is formed by forming on the epitaxial substrate a first buffer layer, an etch termination layer, a second buffer layer, and the sacrificial layer in the order as specified.