Patent ID: 8772126

Claim:
A method of manufacturing a semiconductor device, the method comprising etching a cavity from a front surface into a semiconductor substrate; providing an etch stop structure from at least one of silicon oxide, silicon nitride and silicon oxynitride at the bottom of the cavity; closing the cavity; grinding the semiconductor substrate from a back surface opposite to the front surface at least up to an edge of the etch stop structure oriented toward the back surface; monitoring, during grinding, a grind stop signal indicating exposure of the etch stop structure; and stopping or controlling the grinding in response to detection of the grind stop signal; wherein providing the etch stop structure comprises providing an etch resistive material at the bottom of the cavity, the etch resistive material being absent in a portion of the cavity above the etch stop structure; and wherein closing the cavity comprises tempering, after providing the etch stop structures, the semiconductor substrate in a hydrogen containing ambient to control a collapse of the cavity above the etch stop structure and to form a contiguous layer of a semiconductor material forming the semiconductor substrate above the collapsed cavity, the etch stop structure forming a buried etch stop island.