Methods for fabricating semiconductor or micromachined devices with metal structures and methods for forming self-aligned deep cavity metal structures

摘要

Methods for fabricating semiconductor or micromachined devices with metal structures and methods for forming self-aligned deep cavity metal structures are provided. A method for fabricating a device with a metal structure includes patterning a mask with an opening perimeter bounding an opening over a substrate. The method includes performing an isotropic etch to etch a shallow portion of the substrate exposed by the opening and a shallow portion of the substrate underlying the opening perimeter of the mask. The method also includes performing an anisotropic etch to etch a deep portion of the substrate exposed by the mask opening and a deep portion of the substrate underlying the opening perimeter of the mask to form a cavity having a bottom surface. Further, the method includes depositing metal over the mask, into the mask opening and onto the bottom surface, wherein the metal on the bottom surface forms the metal structure.