PRODUCTION OF ELASTIC SURFACE WAVE ELEMENT

• Main Authors: TAKEZAKI TOORU, WAJIMA SHIYOUSUKE, YAMASHITA KIYOBUMI
• Format: Patent
• Language: English
• Published: 27.12.1985
• Edition: 4
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

PURPOSE:To prevent the disconnection of electrodes to prevent the degradation of frequency characteristics by forming normal interdigital electrodes in the center part of a metallic film vapor-deposited on a piezoelectric substrate. CONSTITUTION:A metallic film 2 is stuck to the upper face of a wafer 1 consisting of the piezoelectric substrate by vapor deposition or the like. After a resist is applied to all of the surface of the metallic film 2, the pattern of normal IDT (interdigital electrodes) 4 and the pattern of weighting IDTs 6 are exposed on the resist in the center part of the wafer 1 and the outside peripheral part of the wafer 1. Thereafter, the resist and the unnecessary metallic film 2 are removed to form IDTs 4 and weighting IDTs 6, and the wafer 1 is cut to obtain elastic surface wave element. Since normal IDTs are formed in the center part of less defects of the metallic film 2 in this manner, the disconnection of IDTs is prevented. Consequently, the degradation of frequency characteristics is prevented.