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Most of the applications of solidly mounted resonator need the compensation of temperature coefficient of resonant frequency. The presence of materials with different properties in the stack makes it complicated to explain the influence of each material individually on temperature coefficient. To reduce design and fabrication costs, an accurate and precise modeling of the resonators is required. In this paper, Mason model and finite-element analysis are used to design the resonators and results for both models, which are almost similar, are presented. Different kinds of configuration (symmetric and asymmetric, according to the thickness of the layers) are designed to achieve the temperature coefficient of frequency as near-zero as possible with an optimized response. Such designs are fabricated and characterized obtaining measurements of the temperature coefficient of frequency. The result shows that useful and reliable information on the performance of resonators can be achieved with accurate modeling. [2017-0107] [ABSTRACT FROM PUBLISHER]

Thin film acoustic wave resonator based devices require compensation of temperature coefficient of frequency (TCF) in many applications. This work presents the design and fabrication of temperature compensated solidly mounted resonators (SMRs). The characteristics of each material of the layered structure have an effect on the device TCF but depending on the relative position with respect to the piezoelectric material in the stack. The influence of material properties of the different layers composing the device on the TCF is discussed in detail. TCF behavior simulation is done with Mason’s model and, to take into account the deterioration of overall performance due to the finite lateral size and shape of the resonator, we have used 2D and 3D finite element modelling of the resonators. The overall behavior of the device for external loads is predicted. SMRs are designed according to simulations and fabricated with different configurations to obtain TCF as near to zero as possible with an optimized response. Resonators are made by depositing Mo/AlN/Mo piezoelectric stacks on acoustic reflectors. As reflector materials, conductive W and insulating WO x films have been used as high acoustic impedance materials. SiO 2 films are used as low acoustic impedance material. [ABSTRACT FROM AUTHOR]