Abstract: A surface acoustic wave device includes a piezoelectric substrate formed from a Ca3Ta(Ga1-xAlx)3Si2O14 single crystal, and an interdigital electrode formed on the surface of the piezoelectric substrate and formed from Al. The interdigital electrode is configured to generate a Love-wave-type SH wave on the surface of the piezoelectric substrate. A normalized film thickness obtained by dividing the film thickness of the interdigital electrode by the wavelength of the Love-wave-type SH wave is 0.16 or less.

Abstract: An oscillation circuit includes an oscillator, first and second capacitors connected between two terminals of the oscillator, and an amplification circuit having an input terminal connected to a connecting point between the oscillator and the first capacitor and an output terminal connected to a connecting point between the first capacitor and the second capacitor. The amplification circuit includes a first n-type transistor and a first p-type transistor respectively having source terminals, the connecting point of which is connected to the output terminal of the amplification circuit, a second p-type transistor connected to a gate terminal of the first n-type transistor, and a second n-type transistor connected to a gate terminal of the first p-type transistor.

Abstract: The present invention makes clear and defines a congruent composition of a langasite-based oxide, and establishes a method of manufacturing a crystal by any desired composition of AE3ME1+a(Ga1?xAlx)3+bSi2+cO14 (AE is an alkaline-earth metal, ME is Nb or Ta, 0?x?1, ?0.5<a?0 or 0<a<0.5, ?0.5<b?0 or 0<b?0.5, and ?0.5<c?0 or 0<c<0.5, excluding a=b=c=0). This makes it possible to suppress the formation of an impurity, and improve the yield and crystal manufacturing rate. The raw material is a raw material mixture prepared by mixing an alkaline-earth metal or its carbonate or oxide, Nb or Ta or its oxide, Ga or its oxide, Al or its oxide, and Si or its oxide.

Abstract: To provide a vibrator made of a piezoelectric crystal having a larger electromechanical coupling coefficient and a more satisfactory frequency-temperature characteristic than those of quartz, a vibrating piece (101) is made of a Ca3Ta(Ga1-xAlx)3Si2O14 single crystal (0<x?1). In the single crystal, letting ? be a rotation angle from an X-Z plane about an X-axis serving as a rotation axis, 18x+17.5???24x+24.5 is set. In addition, the vibrating piece (101) is made of a Ca3Nb(Ga1-xAlx)3Si2O14 single crystal (0<x?1). In the single crystal of this arrangement, letting ? be a rotation angle from an X-Z plane about an X-axis serving as a rotation axis, 25x+23.083???32x+26.167 is set.

Abstract: To improve the Q value of a piezoelectric thin-film element in a state in which unnecessary vibration is suppressed, an acoustic reflection film (104) is affixed to a first electrode (102), a piezoelectric single-crystal substrate (101) is thinned by polishing from the other surface (101b) of the piezoelectric single-crystal substrate (101), such that the first electrode (102) and piezoelectric thin film (105) are piled on the piezoelectric single-crystal substrate (101). In this polishing, a pressure (polishing pressure) to the surface (101b) during polishing in an electrode formation region where the first electrode (102) is formed differs from that in a non-electrode formation region around the electrode formation region. Consequently, the electrode formation region of the piezoelectric thin film (105), where the first electrode (102) is formed, is made thinner than the non-electrode formation region around the electrode formation region.

Abstract: To provide a vibrator made of a piezoelectric crystal having a larger electromechanical coupling coefficient and a more satisfactory frequency-temperature characteristic than those of quartz, a vibrating piece (101) is made of a Ca3Ta(Ga1-xAlx)3Si2O14 single crystal (0<x?1). In the single crystal, letting ? be a rotation angle from an X-Z plane about an X-axis serving as a rotation axis, 18x+17.5???24x+24.5 is set. In addition, the vibrating piece (101) is made of a Ca3Nb(Ga1-xAlx)3Si2O14 single crystal (0<x?1). In the single crystal of this arrangement, letting ? be a rotation angle from an X-Z plane about an X-axis serving as a rotation axis, 25x+23.083???32x+26.167 is set.