Abstract: A method of producing a surface acoustic wave device includes the steps of forming a first electrode film for constituting an interdigital electrode, a wiring electrode, and an electrode pad on the piezoelectric substrate, forming an insulation film on the piezoelectric substrate so as to cover the first electrode film, patterning the insulation film so that the insulation film existing on the portion of the first electrode film onto which a second electrode film is to be laminated is removed, forming the second electrode film on the portion of the first electrode film from which the insulation film has been removed, and bonding a bump onto the second electrode film.

Abstract: A demultiplexer includes an antenna terminal, a reception filter connected to the antenna terminal, a transmission filter connected in parallel to the reception filter with respect to the antenna terminal and having a pass band center frequency that is different from the reception filter, a common inductance component connected between the ground terminal of the transmission filter and the ground terminal of the reception filter, and inductance components, which are different from the common inductance component, provided between the common inductance component and the reception filter and between the common inductance component and the transmission filter.

Abstract: A method for manufacturing a surface acoustic wave apparatus to be mounted via bumps by a flip chip bonding system prevents peeling of electrode pads from the piezoelectric substrate and cracks in the piezoelectric substrate from occurring during the formation of the bumps or at other times during the manufacturing process. In the method of manufacturing a surface acoustic wave apparatus, a first electrode layer of the electrode pad is formed on a piezoelectric substrate by etching, an electrode for a surface acoustic wave element is formed by a lift-off method after the first electrode layer is formed, and thereafter, an electrode film including a second electrode layer of the electrode pad and a wiring electrode is formed.

Abstract: A method of producing a surface acoustic wave device includes the steps of forming a first electrode film for constituting an interdigital electrode, a wiring electrode, and an electrode pad on the piezoelectric substrate, forming an insulation film on the piezoelectric substrate so as to cover the first electrode film, patterning the insulation film so that the insulation film existing on the portion of the first electrode film onto which a second electrode film is to be laminated is removed, forming the second electrode film on the portion of the first electrode film from which the insulation film has been removed, and bonding a bump onto the second electrode film.

Abstract: A demultiplexer includes an antenna terminal, a reception filter connected to the antenna terminal, a transmission filter connected in parallel to the reception filter with respect to the antenna terminal and having a pass band center frequency that is different from the reception filter, a common inductance component connected between the ground terminal of the transmission filter and the ground terminal of the reception filter, and inductance components, which are different from the common inductance component, provided between the common inductance component and the reception filter and between the common inductance component and the transmission filter.

Abstract: A method for manufacturing a surface acoustic wave apparatus to be mounted via bumps by a flip chip bonding system prevents peeling of electrode pads from the piezoelectric substrate and cracks in the piezoelectric substrate from occurring during the formation of the bumps or at other times during the manufacturing process. In the method of manufacturing a surface acoustic wave apparatus, a first electrode layer of the electrode pad is formed on a piezoelectric substrate by etching, an electrode for a surface acoustic wave element is formed by a lift-off method after the first electrode layer is formed, and thereafter, an electrode film including a second electrode layer of the electrode pad and a wiring electrode is formed.

Abstract: A method for manufacturing a surface acoustic wave apparatus to be mounted via bumps by a flip chip bonding system prevents peeling of electrode pads from the piezoelectric substrate and cracks in the piezoelectric substrate from occurring during the formation of the bumps or at other times during the manufacturing process. In the method of manufacturing a surface acoustic wave apparatus, a first electrode layer of the electrode pad is formed on a piezoelectric substrate by etching, an electrode for a surface acoustic wave element is formed by a lift-off method after the first electrode layer is formed, and thereafter, an electrode film including a second electrode layer of the electrode pad and a wiring electrode is formed.

Abstract: A method of producing a surface acoustic wave device by use of a flip chip process, includes the steps of forming on a piezoelectric substrate at least one interdigital transducer and a plurality of electrode pads electrically connected to the interdigital transducer, forming bumps on the respective electrode pads, and providing an insulating film at a region other than a region where the bumps are formed.

Abstract: A method for manufacturing a surface acoustic wave apparatus to be mounted via bumps by a flip chip bonding system prevents peeling of electrode pads from the piezoelectric substrate and cracks in the piezoelectric substrate from occurring during the formation of the bumps or at other times during the manufacturing process. In the method of manufacturing a surface acoustic wave apparatus, a first electrode layer of the electrode pad is formed on a piezoelectric substrate by etching, an electrode for a surface acoustic wave element is formed by a lift-off method after the first electrode layer is formed, and thereafter, an electrode film including a second electrode layer of the electrode pad and a wiring electrode is formed.

Abstract: A surface acoustic wave device is arranged such that surface acoustic wave energy is trapped substantially perpendicularly to the surface acoustic wave propagation direction. At least one interdigital transducer having a plurality of electrode fingers and first and second bus bar electrodes is located on a piezoelectric substrate on which a surface acoustic wave is excited, and has an anisotropy index &ggr; of less than about −1 in the propagation direction. The electrode fingers each have a film thickness of not less than about 0.04 &lgr; in which &lgr; is the wavelength of the surface acoustic wave. At least a portion of the first and second bus bar electrodes have a thickness that is larger than that of each electrode finger.

Abstract: A surface acoustic wave device is arranged such that surface acoustic wave energy is trapped substantially perpendicularly to the surface acoustic wave propagation direction. At least one interdigital transducer having a plurality of electrode fingers and first and second bus bar electrodes is located on a piezoelectric substrate on which a surface acoustic wave is excited, and has an anisotropy index &ggr; of less than about −1 in the propagation direction. The electrode fingers each have a film thickness of not less than about 0.04&lgr; in which &lgr; is the wavelength of the surface acoustic wave. At least a portion of the first and second bus bar electrodes have a thickness that is larger than that of each electrode finger.

Abstract: A method of producing a surface acoustic wave device by use of a flip chip process, includes the steps of forming on a piezoelectric substrate at least one interdigital transducer and a plurality of electrode pads electrically connected to the interdigital transducer, forming bumps on the respective electrode pads, and providing an insulating film at a region other than a region where the bumps are formed.