Abstract—Surface acoustic wave (SAW) devices are used in many areas of telecommunications, and other areas where precise filtering is need. New devices and specification require tighter control of the filtering devices. This is a problem for SAW filters because they often have a large temperature coefficient. Some crystal cuts of quartz can manage the temperature affects and there have been other methods proposed to compensate for the temperature affects of some SAW devices. In this paper a novel method of SAW temperature compensation is proposed consisting of oxide trenches in a silicon substrate for an AlN SAW device. Along with the oxide trenches changes in the oxide trench sidewall angle allow for the adjustment of the second order TCF of the device. Using simulations the first order TCF was reduced from -26.7 ppm to 0 and it was possible to reduce the second order TCF from -24.7 ppb to -1.8 ppb.

Index Terms—aluminum nitride, temperature compensation, AlN SAW, surface acoustic wave

Cite: Andrew B. Randles, Julius M. Tsai, Piotr Kropelnicki, and Hong Cai, "Temperature Compensated AlN Based SAW," Jounal of Automation and Control Engineering, Vol. 2, No. 2, pp. 191-194 June, 2014. doi: 10.12720/joace.2.2.191-194