Method for fabricating RF resonators and filters

A method of manufacturing an RF filter composed of a resonator array, comprises: obtaining a removable carrier; growing a piezoelectric film; applying a first electrode to a film; preparing a back film on a silicon cover; attaching the back film to the first electrode; separating the removable carrier; measuring and trimming the piezoelectric film; fabricating a resonator island; etching down through a coating and the back film to a silicon dioxide layer to form a trench; applying a passivation layer to the trench and a piezoelectric island; depositing a second electrode layer; adding a connection to a transfer circuit board; removing the second electrode material to leave a resonator array; constructing a surrounding gasket around the perimeter of the array; thinning the silicon cover; drilling holes in the silicon cover, etching off the silicon dioxide, fabricating an upper cavity between the back film and the silicon cover; dividing the wafer into a unit filter array; acquiring thetransfer circuit board; applying a dam to the transfer circuit board; coupling the unit filter array to the transfer circuit board through a reflow soldering tin head ; performing bottom packaging byusing a polymer; and separating the filter module.