Surface acoustic wave interdigital transducer response to Deep UV illumination in AlGaN/sapphire

Aluminum-gallium nitride (AlGaN) alloys are promising materials for wavelength-tunable solar-blind surface acoustic wave (SAW) ultraviolet (UV) sensors. We investigate the physical origin of SAW frequency/phase change and study the impact of UV illumination on performance of SAW interdigital transducers (IDT) deposited on AlGaN surface. We correlate these investigations with low frequency measurements of IDT photocapacitance and photoconductance. Our results are important for design and development of efficient SAW devices for UV sensing and high performance filters with tunable frequency response for signal processing applications.