Patent ID: 6710508
Filing Date: 2004-03-23
Classification: H03H

Abstract:
A method of achieving a resonant frequency of acoustic resonators comprising:fabricating a plurality of said acoustic resonators on a basis of forming each said acoustic resonator to include an electrode-piezoeletric stack in which layer dimensions are selected to achieve an intended operational resonant frequency, said intended operational resonant frequency being a target final operational resonant frequency, each said electrode-piezoelectric stack having conductive electrode layers; determining whether said acoustic resonators have current resonant frequencies that are within an acceptable margin of error of said intended operational resonant frequency; and for occasions in which said current resonant frequencies are outside of said acceptable margin of error, exposing said acoustic resonators to a controlled gaseous environment in which at least one said electrode layer is oxidized, including intentionally regulating said controlled gaseous environment on a basis of providing each said acoustic resonator with a final operational resonant frequency that is within said margin of error of said intended operational resonant frequency; wherein said exposing includes regulating said temperature and oxygen content to provide a downward adjustment of said resonant frequencies in a controlled manner, said exposing further including controlling flow rates of gases, including oxygen.