MANUFACTURING METHOD OF ACOUSTIC WAVE ELEMENT, MANUFACTURING METHOD OF ELECTRONIC DEVICE, MASK AND MANUFACTURING METHOD OF MASK

PROBLEM TO BE SOLVED: To improve property of an acoustic wave element, and improve an yield ratio of the acoustic wave element. SOLUTION: A piezo-electric film 13 is formed on a substrate 10, a conductive film 17 is formed on the piezo-electric film 13. After a conductive film 19b which positions on the conductive film 17, and is electrically connected to a comb teeth type electrode 19a, is formed further, while the comb teeth type electrode 19a for generation of the elastic wave is formed on the piezo-electric film 13, a protection film 21 which covers the comb teeth type electrode 19a, and has an opening part OA2, is formed on the conductive film 19b. As a result, connection failures are reduced because it is possible to pass through at a time of wire bonding even if etching residue remains at a bottom of the opening part OA2 at a time of forming the opening part OA2, i.e., etching of the protection film 21. COPYRIGHT: (C)2007,JPO&INPIT