公开(公告)号：US09458009B2

公开(公告)日：2016-10-04

申请号：US14798112

申请日：2015-07-13

Applicant: Infineon Technologies AG

Inventor： Alfons Dehe ,  Carsten Ahrens ,  Stefan Barzen ,  Wolfgang Friza

IPC: B81C1/00 ,  B81B3/00

CPC classification number: B81B3/0072 ,  B81B3/001 ,  B81B3/0027 ,  B81B2201/0257 ,  B81B2203/0127 ,  B81B2203/0315 ,  B81C1/00182 ,  B81C1/00404 ,  B81C1/00984 ,  B81C2201/017 ,  B81C2201/115

Abstract: In accordance with an embodiment of the present invention, a method of forming a semiconductor device includes forming a sacrificial layer over a first surface of a workpiece having the first surface and an opposite second surface. A membrane is formed over the sacrificial layer. A through hole is etched through the workpiece from the second surface to expose a surface of the sacrificial layer. At least a portion of the sacrificial layer is removed from the second surface to form a cavity under the membrane. The cavity is aligned with the membrane.