Patent ID: 7989250
Filing Date: 2011-08-02
Classification: G02B

Abstract:
1. A method of fabricating a membrane structure for a diffractive phased array assembly, comprising the steps of: a) providing a wafer having a body and at least a membrane layer and a backside layer disposed on opposite faces of the body, and an etch-stop layer underlying the membrane layer; b) forming a grating pattern in the surface of the membrane layer adjacent the wafer body; c) forming a window through the wafer to expose a back surface of the membrane, thereby allowing light to pass through the membrane; d) etching through the wafer and etching through the etch-stop layer to the membrane layer to form the window; and e) mounting the membrane structure in a protective fixture prior to the step of etching through the etch stop layer, in order to protect the membrane layer.