Surface acoustic wave device and manufacturing method thereof

Abstract

A surface acoustic wave device includes an excitation electrode formed on a piezoelectric substrate and a binding electrode to be connected with a mounting substrate. The binding electrode is provided with a lower electrode formed on the piezoelectric substrate and an intermediate layer that is made of an adhesion electrode layer and a barrier metal electrode layer. The barrier metal electrode layer includes at least one impurity-containing layer. The binding electrode represents an annular electrode formed to surround the excitation electrode and a wiring electrode connected to the excitation electrode. A surface of at least one of the piezoelectric substrate, the lower electrode and the barrier metal electrode layer is bombarded to make it a rough surface. As a result, a warp due to a film stress caused in each of the layers can be suppressed.

Description

technical field [0001] The invention relates to a surface acoustic wave device and a manufacturing method thereof. The surface acoustic wave device is particularly suitable for use in wireless communication circuits in mobile communication equipment and the like. Background technique [0002] Surface acoustic wave devices including surface acoustic wave resonators, surface acoustic wave filters, and the like are used in a wide range of applications such as various types of wireless communication equipment using microwave bands, in-vehicle equipment, and medical equipment. Also, as devices are reduced in size, surface acoustic wave devices are required to be reduced in size. [0003] FIG. 9 is an outline cross-sectional view of a typical surface acoustic wave device 100 according to the prior art. [0004] The surface acoustic wave device 100 includes a surface acoustic wave element S and a mounting substrate 120 . The surface acoustic wave element S is provided with: a pi...

AI Technical Summary

Problems solved by technology

When the flash is deposited in an area larger than the design area, the flash may short the IDT electrode 111

[0023] Also, since the burrs are deposited very thinly, the burrs are weakly attached to the substrate or electrode and easily come off

When the burr falls off, the burr tends to short circuit with the adjacent electrode, causing the characteristic failure of the surface acoustic wave device

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