Method for Processing a Wafer at Unmasked Areas and Previously Masked Areas to Reduce a Wafer Thickness

摘要

A method for processing a wafer having microelectromechanical system structures at the first main surface includes applying a masking material at the second main surface and structuring the masking material to obtain a plurality of masked areas and a plurality of unmasked areas at the second main surface. The method further includes anisotropically etching the wafer from the second main surface at the unmasked areas to form a plurality of recesses. The masking material is then removed at least at some of the masked areas to obtain previously masked areas. The method further includes anisotropically etching the wafer from the second main surface at the unmasked areas and the previously masked areas to increase a depth of the recesses and reduce a thickness of the wafer at the previously masked areas.