Saw device having a plurality of electrodes and a fabrication method thereof

• Main Authors: MIYASHITA, TSUTOMU, SATOH, YOSHIO
• Format: Patent
• Language: English; French; German
• Published: 28.02.1996
• Edition: 5
• Subjects: BASIC ELECTRONIC CIRCUITRY; ELECTRICITY; IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS

A surface-acoustic-wave device comprises a substrate (51) of a piezoelectric material for providing a passage (CH) of surface acoustic waves at an upper major surface of the substrate, a plurality of interdigital electrodes (71, 72) provided on the piezoelectric substrate in a row in correspondence to the passage of surface acoustic waves such that the electrodes are aligned in the propagating direction of the surface acoustic waves, each of the plurality of interdigital electrodes having a first part (EL1, EL1 min ) connected to a bonding pad (78, 78 min ) on the substrate for external electric connection and having a plurality of finger electrodes (f1 - fn) extending parallel with each other in a direction crossing the propagating surface acoustic waves, and a second part (EL2, EL2 min ) separated from the first part and having a plurality of finger electrodes (g1 - gn) extending parallel with each other in a direction opposite to the direction of the finger electrodes of the first part. An interconnection pattern (54) is provided on the surface of the substrate in correspondence to a region offset from the passage of the surface acoustic waves for connecting the second parts of adjacent interdigital electrodes with each other.