Method for manufacturing elastic wave device, and elastic wave device
AssigneeMurata Manufacturing Co., Ltd.
InventorTakashi Iwamoto
Life of this patent
Estimating the term…
Abstract
A method for manufacturing an elastic wave device includes successively stacking conductive films on a piezoelectric substrate on which a pattern of a first resist has been formed, removing the first resist from the piezoelectric substrate on which the conductive films have been stacked; applying a second resist to the piezoelectric substrate from which the first resist has been removed and subjecting the second resist to exposure and development, thus forming a protective layer that protects a first region with the second resist, and etching the second conductive material in a state in which the first region is protected by the protective layer.
Claims6
An elastic wave device comprising:
- a piezoelectric substrate;
- a first comb-shaped electrode disposed on a principal surface of the piezoelectric substrate;
- and
- a second comb-shaped electrode disposed on the principal surface of the piezoelectric substrate and having a thickness smaller than a thickness of the first comb-shaped electrode;
- wherein
- the first comb-shaped electrode includes a larger number of layers than the second comb-shaped electrode;
- an uppermost layer of the first comb-shaped electrode and an uppermost layer of the second comb-shaped electrode are made of different conductive materials;
- a surface of the uppermost layer of the second comb-shaped electrode is resistant to etching;
- the first comb-shaped electrode and the second comb-shaped electrode are tapered so that widths thereof decrease with increasing distance in a direction away from the piezoelectric substrate;
- and
- the layers of the first comb-shaped electrode include at least one etching stop layer defined by an oxidized layer.
Dependencies are inferred from the claim text.