Gas sensor for sensor network using resonators with double-reflection SAWS to achieve large interaction areas within small chip

We have studied a new SAW sensor which can be installed in sensor network. Three items have been investigated based on new ideas: (1) we achieved the self-temperature-compensation characteristics which guaranteed the garage use at -40 to 80 °C and removed the limitation for piezoelectric crystal substrates such as a Quartz substrate; (2) we developed a new lattice-circuit type low-loss sensor consisting of SAW resonators which could make it possible to be included in sensor nodes; (3) in order to increase the sensing sensitivity we proposed a double-reflection type SAW resonators which had effectively expanded the interaction areas reactive to sensing gas without increasing chip size. In this paper, we will summarize (1) and (2), and show the possibility of (3).