The studied resonator is part of an industrial project carried by NXP Semiconductors. The objective is the realization of a integrable RF MEMS resonator in order to replace quartz in some applications. The compatibility of the manufacturing process with the technologies used by the company and low cost production represent the main challenges of the project. The resonator TFEAR (Thin Film Elongation Acoustic Resonator) is a bar, consisting of a superposition of thin film type Metal/AlN/metal. The piezoelectric properties of aluminum nitride (AlN) are exploited : the application of an alternating electric field, parallel to the thickness of the bar, resulting in propagation of acoustic waves along its length. The sizes of the manufactured resonators correspond to resonant frequencies between 10MHz to 50 MHz. This thesis focuses on modeling and electrical characterization of the TFEAR resonator. The models are developed by 3D numerical simulations and by 1D analytical calculations. The electrical behavior of TFEAR is described by an equivalent circuit which elements are expressed in terms of physical parameters and losses of the constituent materials. A quality factor of 2250 on a 25.79MHz resonant TFEAR which motional resistance is 2.1 kOhms has been noticed. These measurements were completed by the characterization of the physical parameters of the piezoelectric layer. For example, piezoelectric coefficient d33;f values were recorded up to 2.6 pm/V (for a theoretical maximum of 3.93pm/V)
