Approach to improve ZnO-based FBAR devices

Abstract

Presented is a new technique to improve the resonance characteristics of film bulk acoustic-wave resonator (FBAR) devices. The FBAR devices were fabricated on multilayer Bragg reflectors into which ultra-thin chromium (Cr) adhesion layers were inserted, followed by several kinds of thermal annealing processes. This technique resulted in excellent device improvement in terms of return loss and Q-factors.