CMOS ULTRASONIC TRANSDUCERS AND RELATED APPARATUS AND METHODS

摘要

CMOS Ultrasonic Transducers and processes for making such devices are described. The processes may include forming cavities on a first wafer and bonding the first wafer to a second wafer. The second wafer may be processed to form a membrane for the cavities. Electrical access to the cavities may be provided.

主权项

1. A method, comprising:
forming a cavity in a first wafer above a complementary metal oxide semiconductor (CMOS) circuit in the first wafer; bonding, using direct bonding, the first wafer and a second wafer together such that the second wafer seals the cavity of the first wafer, thereby forming a sealed cavity, the second wafer being a silicon-on-insulator wafer or a bulk silicon wafer having a degeneratively doped layer; and forming an ultrasonic transducer membrane from the second wafer subsequent to bonding the first and second wafers together.