Silicon-based Surface Acoustic Wave resonators for more sustainable RF integrated filters

Electronic devices are taking more and more place in our lives and are becoming increasingly com-plex. The communication system, which is a key part of these devices, is becoming more efficientand smaller, and new technologies such as 5G are putting even more pressure on these devices. Specific technologies and materials are needed to meet the requirements for these huge performances.However, this comes at a cost, which is economic but also environmental and social, and cannot beneglected anymore. This thesis is focused on piezoelectric resonators, which are the base elements used in filters forradio frequency communication. More specifically, surface acoustic wave (SAW) resonators are studied. These resonators are made of piezoelectric materials, materials which, thanks to their particular structure, have specific electromechanical properties which make them particularly suitable for thisapplication. The focus will be set on three different technologies. Two of them are using the samepiezoelectric material, lithium tantalate. The first technology uses a substrate made only of lithiumtantalate, while the second technology, called piezo-on-insulator (POI), uses a multilayer substratemade of a thin layer of lithium tantalate on a silicon substrate, with both layers separated by anoxide layer. The alternative to lithium tantalate which will be studied is aluminium nitride. Based on an analysis of both the performances and the sustainability of these three technologies,the aim of this thesis is to determine which is the most suitable for the SAW resonators of tomorrow