University of Minnesota

Korea Institute of Science and Technology

Joon Han Kim

Hyung Jin Jung

Dennis L Polla

Tae Song Kim

Jeon-Kook Lee

Dong Heon Lee

A micromechanical device or microactuator based upon the piezoelectric, pyroelectric, and electrostrictive properties of ferroelectric thin film ceramic materials such as PZT. The microdevice has a device substrate and a deflectable component. The deflectable component is mounted for deflection on the device substrate and has a sensor/actuator. The sensor/actuator has first and second electrodes and a piezoelectric thin film disposed between the first and second electrodes. The thin film is preferably PZT. The sensor/actuator is disposed on a sensor/actuator substrate. The sensor/actuator substrate is formed of a material selected for being resistive to attack by hydrofluoric acid vapor. The invention also relates to a method for fabricating such micromechanical devices or microactuators.

PZT microdevice

A PZT ferroelectric thin film is sputter deposited on an electrode without microcracks while avoiding oxygen and Pb ion deficiencies at the electrode interface by initially forming a buffer layer containing a sufficient amount of a volatile Pb component and a sufficient amount of oxygen to easily absorb the energy of sputter particles. The PZT ferroelectric thin film can also be deposited by laser ablation.

Method for fabricating ferroelectric thin film

Growing community of inventors

Seoul, South Korea

Joon Han Kim