| 摘要 |
PURPOSE:To improve the width accuracy of an electrode finger and to assure the connection of a bonding part by coating the 1st metallic film on a piezoelectric substrate to obtain plural electrodes, coating the 2nd metallic film on those electrodes and deleting the 2nd metallic film excluding the electrode bonding part. CONSTITUTION:A metallic film 12 vapor-deposited with gold, for example, is coated on a piezoelectric substrate 11 of LiNbO3, etc. Then a resist film 13 is coated on the substrate 11 and the film 12 is etched with an aqua regia etching solution after exposure and development. Thus a prescribed electrode is obtained, and the undesired film 13 is deleted. Thus an electrode 14 is produced. Then Al, for example, is vapor-deposited and the 2nd metallic film 15 is coated by a sputtering process, etc. Then a resist film 16 is formed only at the bonding part of the electrode 14. The film 15 is etched with a mixed solution of nitric acid, phosphoric acid, acetic acid, etc. to delete the undesired film 16. Therefore only a bonding part 17 on the electrode 14 increases its thickness for a surface acoustic wave device 18. |
