Cavity structures for MEMS devices

摘要

Embodiments relate to MEMS devices, particularly MEMS devices integrated with related electrical devices on a single wafer. Embodiments utilize a modular process flow concept as part of a MEMS-first approach, enabling use of a novel cavity sealing process. The impact and potential detrimental effects on the electrical devices by the MEMS processing are thereby reduced or eliminated. At the same time, a highly flexible solution is provided that enables implementation of a variety of measurement principles, including capacitive and piezoresistive. A variety of sensor applications can therefore be addressed with improved performance and quality while remaining cost-effective.

主权项

1. A method of forming a monolithic integrated sensor device comprising:
forming a microelectromechanical system (MEMS) device on a non-silicon-on-insulator (non-SOI) substrate by:
forming a monocrystalline sacrificial layer on only a first portion of the non-SOI substrate,depositing a first silicon layer on the monocrystalline sacrificial layer and on a second portion of the non-SOI substrate different from the first portion,forming a cavity in the monocrystalline sacrificial layer via at least one release aperture in the first silicon layer, andsealing the cavity by depositing a second silicon layer; and forming a transistor on the second portion of the non-SOI substrate, the transistor comprising at least a portion of the second silicon layer.