Nowadays, various competitions between manufacturers take place in the field of MEMS (Micro- Electro-Mechanical Systems), due to the quest for continuous performance improvement in terms of miniaturisation, integration, costs effectiveness etc. This thesis is a step towards the development of IC-compatible bulk acoustic MEMS resonators. The main goal consists in validating the principle of electrostatic actuation of the thickness‒extensional acoustic waves into mono-crystalline substrates and also to explore the energy-trapping possibility provided by this mode. A novel single-port silicon structure fixed on a glass support was studied and analytically modelled to be implemented into a micro-fabrication process. The original models elaborated for a structure vibrating in both thickness‒extensional and flexural modes allowed the estimation of the electrical equivalent circuit parameters and of the static and dynamic mechanical displacements. A two-dimensional theoretical approach based on the dispersion curves estimation of a silicon plate was presented and the means to localize the acoustic energy in the central region of the structure were evaluated. By using the available micro-manufacturing techniques at the MIMENTO facility of the FEMTO-ST Institute, several runs were performed on silicon wafers. The resonators fundamental vibration frequencies range around 10 MHz for the thickness-extensional mode and around 70 KHz for the flexural mode. The electrical and mechanical characterisation results are thoroughly presented. The devices operating in flexural modes were successfully embedded into a customized Wienbridge oscillator design. Finally a gravimetric sensor application was demonstrated.
