Implementation of frequency scanning function in phase sensitive laser probe system for RF SAW/BAW devices

The authors has been developing phase-sensitive and fast mechanical scanning laser probe system as a diagnosis tool for RF SAW/BAW devices. This paper describes implementation of the frequency scanning function to the system. Little modification of the preexisting hardware and a newly developed Windows GUI program enable automated frequency scanning operation without sacrificing original functions. A data filtering program optimized for use in batch processing was newly developed for post processing of vast data acquired by the frequency scanning. As a demonstration, field distributions of a one-port SAW resonator on 42YX-LiTaO₃ were captured for the frequency span from 820 to 880 [MHz] with every 0.25 MHz step (241 frequency points). After around 31.5 hours in total, we got an animation revealing how SAW field changes with the frequency.