MEMS DEVICES AND METHODS OF FORMING SAME

摘要

The present invention provides a MEMS structure comprising confined sacrificial oxide layer and a bonded Si layer. Polysilicon stack is used to fill aligned oxide openings and MEMS vias on the sacrificial layer and the bonded Si layer respectively. To increase the design flexibility, some conductive polysilicon layer can be further deployed underneath the bonded Si layer to form the functional sensing electrodes or wiring interconnects. The MEMS structure can be further bonded to a metallic layer on top of the Si layer and the polysilicon stack.

主权项

1. A micro-electromechanical system (MEMS), comprising:
a substrate; an isolation layer on top of the substrate, wherein the isolation layer comprises silicon nitride; a sacrificial layer on top of the isolation layer, wherein the sacrificial layer has a flat surface and at least one opening extending therethrough; a wafer layer bonded to the sacrificial layer, wherein the wafer layer has at least one MEMS via; a conductor stack within the at least one MEMS via; a MEMS structure formed in the wafer; and a cavity between the isolation layer and the MEMS structure.