Invited Paper MN+NS-TuM1
Science and Technology of Integrated Piezoelectric and Ultrananocrystalline Diamond Films for a New Generation of High Performance MEMS and NEMS Devices

Tuesday, October 29, 2013, 8:00 am, Room 102 A

This review will focus on a discussion of the science and technology for a novel integration of ultrananocrystalline diamond (UNCD) and piezoelectric thin films to enable a new generation of hybrid piezo/diamond heterostructures for low voltage piezoactuated high-performance diamond-based MEMS/NEMS devices. A main component of the new MEMS/NEMS systems is the new UNCD film discovered, developed and patented by our group. UNCD exhibits multifunctionalities applicable to a broad range of multifunctional devices from the macro to the nanoscale. UNCD films are grown using plasma enhanced chemical vapor deposition (PECVD) with a new patented Ar-rich/CH₄ chemistry, which yields insulating films with 2-5 nm grains and 0.4 nm wide grain boundaries or electrically conductive films (NUNCD), with 10 nm grains and 1-2 nm grain boundaries, via nitrogen incorporation into grain boundaries when growing the film with an Ar/CH₄/N₂ gas mixture.

Concurrently with the development of the UNCD film technology, our group has been developing a ferroelectric/piezoelectric thin film technology, based on three main piezo materials (PbZr_xTi_1-xO₃, AlN, and the newest BiFeO₃), and the UNCD/piezoelectric thin films integration, which are being used to develop new low voltage/high performance piezoactuated MEMS/NEMS devices for several applications, namely: energy harvesting devices, piezoactuated NEMS switches for a new NEMS logic, biosensors, implantable MEMS/NEMS drug deliver devices, and biologically enabled piezo-MEMS micro-power generators.

In addition to the application to piezo-actuated MEMS, UNCD has been demonstrated as a unique dielectric with fast charging-discharging (in the microsecond range) layer that eliminates RF MEMS switch charging-induced failure, due to fast charge motion in and out of the film through the nano-grain boundaries, enabling a new technology based on reliable RF-MEMS switches integrated with driving CMOS devices for a new generation of phase array antennas for radars and mobile communication devices.