Patent ID: 9556017
Date: 2017-01-31
CPC Classifications: B81B,B81C

Claim:
1. A method for forming stopper features on an ASIC wafer to prevent over-range movement of a movable MEMS structure coupled to the ASIC wafer, the ASIC wafer including a top circuitry layer, the method comprising: forming an HDP-OX etch-stop layer above the top circuitry layer; forming a passivation layer on the HDP-OX etch-stop layer; selectively etching the passivation layer to form at least one selectively etched stopper feature comprising a remaining unetched portion of the passivation layer, wherein the HDP-OX etch-stop layer is an etch-stop layer for patterning the passivation layer; and positioning the movable MEMS structure on the ASIC wafer so that the at least one selectively etched stopper feature is opposite the movable MEMS structure within a range of movement of the movable MEMS structure to prevent over-range movement of the movable MEMS structure.