| Our Research is aimed at developing a new generation of microwave
electronic devices based on Gallium Nitride (GaN), an emerging wide
band-gap semiconductor material. GaN devices promise high speed
performance similar to GaAs, but with dramatically higher breakdown
voltages and power handling capacity. GaN devices have been
demonstrated at UCSB with power densities greater than
twenty times that
of GaAs, and further improvements in materials quality could
increase that
factor further. Progress has been
extremely rapid.
The GaN research efforts at UCSB spans materials growth through device
fabrication to circuit design and development, and involves a large
number of student in the ECE and Materials departments. Research
under Professor York is primarily in the area of device and circuit
design. We have developed a full GaN MMIC
process and implemented LNAs, oscillators, and power-amplifiers.
Historically we also implemented hybrid wideband power amplifiers using a
flip-chip approach onto thin-film ceramic (AlN) coplanar waveguide
circuits. Efforts are now underway to extend this work
to other functionality for low-noise and high-speed microwave
electronics, possibly incorporating thin-film ferroelectrics for
enhanced performance. |