Method for making potassium niobate thin film, surface acoustic wave element, frequency filter, frequency oscillator, electronic circuit and electronic apparatus
AssigneeSeiko Epson Corporation
InventorsTakamitsu Higuchi, Setsuya Iwashita, Hiromu Miyazawa
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Abstract
A method is provided for forming a potassium niobate thin film in which, in a process of manufacturing a surface acoustic wave element, a conductive thin film included in the surface acoustic wave element is used as an electrode for applying an electric field to the potassium niobate thin film that is to serve as the piezoelectric layer of the surface acoustic wave element to polarize it. A surface acoustic wave element, a frequency filter, a frequency oscillator, an electronic circuit, and an electronic apparatus are also provided.
Claims11
A method for making a potassium niobate thin film subjected to polarization by applying an electric field thereto, the method comprising the step of:
- depositing a conductive first thin film on the potassium niobate thin film, the first thin film functioning as an interdigital electrode of a surface acoustic wave element when the potassium niobate thin film is used as a piezoelectric layer of the surface acoustic wave element,
- wherein the first thin film is used as an electrode for applying the electric field to the potassium niobate thin film.
A method for making a potassium niobate thin film subjected to polarization by applying an electric field thereto, the method comprising the steps of:
- depositing a conductive first thin film on the potassium niobate thin film, the first thin film functioning as an interdigital electrode of a surface acoustic wave element when the potassium niobate thin film is used as a piezoelectric layer of the surface acoustic wave element;
- and
- depositing another conductive thin film on another surface of a crystal substrate of the surface acoustic wave element,
- wherein the first thin film and the other thin film are used as electrodes for applying the electric field to the potassium niobate thin film.
A surface acoustic wave element comprising:
- a piezoelectric layer comprising a potassium niobate thin film;
- a conductive first thin film formed on a surface of the piezoelectric layer;
- and
- a conductive second thin film formed on another surface of the piezoelectric layer,
- wherein the piezoelectric layer is subjected to electric field application to be polarized, using the first thin film and the second thin film as electrodes.
A surface acoustic wave element comprising:
- a piezoelectric layer comprising a potassium niobate thin film;
- a first conductive thin film formed on a surface of the piezoelectric layer;
- and
- another conductive thin film formed on a first surface of a crystal substrate, the piezoelectric layer being on a second surface of the crystal substrate,
- wherein the piezoelectric layer is subjected to electric field application to be polarized, using the first conductive thin film and the other conductive thin film as electrodes.
Dependencies are inferred from the claim text.