National Nanofab Center Ministry of Science and ICT KAIST

AlN Thin Film-based MEMS Process Platform

This is an ultrasonic transducer/resonator-based sensor platform utilizing the piezoelectric properties of C-axis oriented AlN thin films.

• -It is characterized by the use of seed layer deposition and Mo electrode for piezoelectric AlN crystallinity.
• To minimize the damage of AlN thin film during the process, TMAH is not used and 1 um AlN thin film patterning is performed using dry etching process.
• DRIE process is performed on the Silicon backside to generate resonance of the device.

• We provide 8-inch based process services, enabling high productivity and the fabrication of various types of devices.
• The high uniformity of AlN films and low residual stress (40>MPa) of 0.5% (1 sigma) allow for the production of MEMS devices with uniform performance.
• High crystallinity (Rocking curve FWHM less than 1.2 degrees) allows for high piezoelectric performance expectations.

• MEMS Sensors: Ultrasonic imagers, ultrasonic distance sensors, ultrasonic gas sensors, bio sensors
• Thin film-based resonators/filters: Due to the high acoustic velocity of AlN, it can be used to manufacture FBAR and filters that can be used in 5G.

The National Nanofab Center has the capability to provide AlN-based thin film MEMS process technology, and services can be provided at the following scope and technology level.
: Support for the development of 200 mm SOI WAFER-based thin film AlN MEMS start-up products