Abstract: Provided is a method for manufacturing an acoustic wave device that has an excellent temperature coefficient of frequency (TCF) and high accuracy of IDT pattern forming and is capable of resisting high temperature processing of 200 degrees or more. The method for manufacturing an acoustic wave device according to the present invention includes forming an IDT (2) on a principal surface (1a) of a piezoelectric substrate (1), and forming a film by thermal spraying a material (3) having a smaller linear thermal expansion coefficient than the piezoelectric substrate onto an opposite principal surface (1b) of the piezoelectric substrate (1) where the IDT (2) is formed.

Abstract: Provided are an acoustic wave device and a method for manufacturing the same, the acoustic wave device being effectively prevented from expanding and contracting due to temperature change and having a small frequency shift. The acoustic wave device of the present invention has a piezoelectric substrate (1) having an IDT (2) formed on one principal surface of the piezoelectric substrate (1), and a thermal spray film (3) formed on an opposite principal surface (1b) of the piezoelectric substrate (1), the thermal spray film being of a material having a smaller linear thermal expansion coefficient than the piezoelectric substrate (1) and having grain boundaries and pores (4), at least a part of which is filled with a filling material (5).

Abstract: Provided are an acoustic wave device and a method for manufacturing the same, the acoustic wave device being effectively prevented from expanding and contracting due to temperature change and having a small frequency shift. The acoustic wave device of the present invention has a piezoelectric substrate (1) having an IDT (2) formed on one principal surface of the piezoelectric substrate (1), and a thermal spray film (3) formed on an opposite principal surface (1b) of the piezoelectric substrate (1), the thermal spray film being of a material having a smaller linear thermal expansion coefficient than the piezoelectric substrate (1) and having grain boundaries and pores (4), at least a part of which is filled with a filling material (5).

Abstract: Provided is a method for manufacturing an acoustic wave device that has an excellent temperature coefficient of frequency (TCF) and high accuracy of IDT pattern forming and is capable of resisting high temperature processing of 200 degrees or more. The method for manufacturing an acoustic wave device according to the present invention includes forming an IDT (2) on a principal surface (1a) of a piezoelectric substrate (1), and forming a film by thermal spraying a material (3) having a smaller linear thermal expansion coefficient than the piezoelectric substrate onto an opposite principal surface (1b) of the piezoelectric substrate (1) where the IDT (2) is formed.

Abstract: A piezo-electric substrate is mainly comprised of a base material and a film formed on one main surface of the base material. In the base material, the main surface on which the film is formed is a roughed main surface. The piezo-electric substrate is obtained by forming the film comprised of a material with a coefficient of linear expansion smaller than a coefficient of linear expansion of the base material on the roughened main surface using a thermal spraying method.

Abstract: A piezo-electric substrate is mainly comprised of a base material and a film formed on one main surface of the base material. In the base material, the main surface on which the film is formed is a roughed main surface. The piezo-electric substrate is obtained by forming the film comprised of a material with a coefficient of linear expansion smaller than a coefficient of linear expansion of the base material on the roughened main surface using a thermal spraying method.