Experimental study on the impact of anchor losses on the quality factor of contour mode AlN resonators

Abstract

This paper presents an experimental study on the impact of anchor losses on the quality factor (Q) of laterally vibrating AlN contour mode resonators for three different resonance frequency devices (220 MHz, 370 MHz, and 1.05 GHz). Anchors of different width (W <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a</sub> ) and length (L <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a</sub> ) were designed as supports for resonators having a vibrating body of identical dimensions. The results confirm that the main source of damping is associated with anchor losses at 220 MHz and interfacial losses at 1.05 GHz. Furthermore, finite element analysis (FEA) was used to model anchor losses in AlN CMRs, exhibiting excellent agreement with the measurements.