A feasibility study of ZnO-based FBAR devices for an ultra-mass-sensitive sensor application

Abstract

We present a feasibility study of ZnO-based FBAR devices and their fabrications for the ultra-mass-sensitive sensor application. In this work, a considerable shift in the resonance frequency is observed due to the mass-loading effect by a mixture of ink and volatile methanol. A high sensitivity of 0.05 x 10(5) Hz (.) cm(2)/ng is obtained in the FBAR-based device, which is similar to5 orders of magnitude higher than that of 0.057 Hz (.) cm(2)/ng reported in the conventional 5-MHz quartz crystal microbalance. This approach seems useful for the ultra-high-mass resolution chemical sensor or biosensor applications. (C) 2004 Wiley Periodicals, Inc.