Abstract: Provided is a surface acoustic wave device using a novel and steadily suppliable piezoelectric material that is resistant to a high-temperature environment and enables the surface acoustic wave device to use a 2 GHz to 2.5 GHz band or higher. The surface acoustic wave device includes: a piezoelectric substrate formed from a monocrystal of gehlenite (CAS: Ca2Al(AlSi)O7); and interdigital transducers formed on a surface acoustic wave propagation plane of the piezoelectric substrate.

Abstract: Provided is a surface acoustic wave device using a novel and steadily suppliable piezoelectric material that is resistant to a high-temperature environment and enables the surface acoustic wave device to use a 2 GHz to 2.5 GHz band or higher. The surface acoustic wave device includes: a piezoelectric substrate formed from a monocrystal of gehlenite (CAS: Ca2Al(AlSi)O7); and interdigital transducers formed on a surface acoustic wave propagation plane of the piezoelectric substrate.

Abstract: A wireless temperature sensor that has an ease of manufacture and an improved reliability is provided. The wireless temperature sensor includes a first structure having an antenna having an antenna electrode and a GND electrode disposed in an insulating substrate, a temperature detection device fixed on an opposite surface of the first structure to a surface in which the antenna electrode is disposed, and a second structure disposed on the side of a side wall of the temperature detection device and joined to the first structure. The temperature detection device is fixed on the first structure so as to be electrically connected to the antenna electrode and the GND electrode.