MEMS 공정에 의해 제작된 PZT 마이크로 켄틸레버의 전기기계적 거동 및 질량에 대한 공진특성 분석

Abstract

A micromachined self-exited piezoelectric cantilever has been fabricated using PZT(52/48) thin film. For the application to biosensor using antigen-antibody interaction, electromechanical properties such as resonant frequency and quality factor of micromachined piezoelectric cantilever were important factors. Electromechanical properties and resonant behaviors of microfabricated cantilever were simulated by FEA (Finite Element Analysis) using CoventorwareTM2003. And these characterization of microcantilever were measured by using LDV(Laser Doppler Vibrometer) to compare with FEA data. We present the resonant frequency shift of micromachined piezoelectric cantilevers due to combination of mass loading and change of spring constant by gold deposition. Experimental mass sensitivities of microcantilever were characterized by Au deposition on the backside of microcantilever. Mass sensitivities with 100 x 300 ㎛ dimension cantilever from simulation and experimental were 5.56 Hz/ng and 16.8 Hz/ng, respectively.