Micro / Nanoelectromechanical Systems (MEMS/NEMS)
provide the advantages of small size, low cost,
low power consumption, low mass, high
reliability, and low maintenance on both the
system as well as the component levels. Our
research interests are to develop and fabricate
mechanical machines that are integrated with
microelectronics at the micron scale. New
device concepts include but are not limited to:
the integration of micro-optics components,
miniature signal processing devices,
biomedical/genome processing devices, miniature
electromechanical wireless components (filters,
mixers, antennas), miniature
opto-electromechanical devices (Optical Cross
Connect, optical relays, optical multiplexers,
deformable optics), miniature biosensors and
environmental sensors, and microfluidics
devices. Issues such as self-testing,
self-assembly, and automated packaging will be
On a smaller scale, the potential applications of
Carbon Nanotubes (CNT) for biomedical instruments
are limitless. CNT exhibit unique properties that
include extremely high mechanical strength, high
thermal conductivity, excellent chemical and
thermal stability. Our lab's nanotechnology
experience will assist in developing novel designs and
fabricating concepts based on CNT/nanotechnology
for next-generation instruments. The ultimate
goal of the research is to realize fully
functioning performance-enhanced biomedical
nanodevices for clinical deployment.
Capacitive Micromachined Ultrasonic Transducers
Since the inception of the lab's CMUT team seven years ago, we have matured into one of the leaders in the field. Our research involves CMUT simulation, fabrication, system integration, and packaging. We have already developed several generations of CMUTs and customized imaging systems.
CMUT can be viewed as a parallel plate capacitor with a movable top plate. When a voltage pulse is applied across the plates, the top plate vibrates and launches an acoustic wave. Due to the unique properties of CMUTs, the bandwidth of an ultrasonic signal generated by a CMUT is much larger than piezoelectric transducers. Ultrasound’s larger bandwidth translates to its ability for a higher axial, or depth, resolution detection.
Part of our previous efforts were to simplify the CMUT fabrication process and reduce the fabrication cost. The CMUTs are created using a fusion wafer bonding technique with regular silicon wafers. As a result, high cost silicon-on-insulator (SOI) wafers, which are used extensively in most other CMUT fabrication processes, are avoided.
Currently, one of our main research objectives is to develop large high-density CMUT arrays for large-area real-time 3D imaging.