Mechanical behavior of T-shaped A1N membrane based on thin film elongation acoustic resonator

Microelectromechanical systems (MEMS) move rapidly towards commercialization, the issue of mechanical characterization has emerged as a major consideration in device design and fabrication. This paper investigates the vibration analysis of T shaped membrane which is fully adapted for oscillator circuit miniaturization. This shape has been actuated by a piezoelectric Aluminum Nitride (AlN) 1 μm-thin layer sandwiched between two aluminum electrodes and fabricated using micromachining technology. Analytical and 3D finite element method (3D-FEM) analysis using Comsol software have been performed to model the modal and mechanical vibration behavior, and to estimate the material properties which minimize the difference between the measured and simulated profiles. Typical numerical simulations and experimental results are presented and discussed. The mechanical characterization uses Laser Doppler Vibrometry (LDV) system which is quick, non-destructive, non-contact, with a high accurate detection of resonance frequency. This work main contribution is mechanical characterization and comparison with its model. The performances of the TFEAR presents a Q factor up to 1200 and a motional resistance close to 400 Ω at 12.78 MHz.