Abstract: A method of manufacturing a power generation element includes a first step of disposing a support unit that supports a vibration unit in one end portion of the vibration unit in one direction, and disposing a weight unit in the other end portion of the vibration unit in the one direction in a substrate including the vibration unit capable of vibrating, a second step of disposing a piezoelectric unit that generates power due to vibration in a portion of the vibration unit on an opposite side from the support unit side in a thickness direction of the substrate after the support unit and the weight unit are disposed in the vibration unit, and a third step of extracting a power generation element from the substrate by cutting an outer edge of the vibration unit in the thickness direction of the substrate after the piezoelectric unit is disposed in the vibration unit.

Abstract: A piezoelectric element includes, in sequence, a substrate, a lower electrode layer, a growth control layer, a piezoelectric layer including, as a main component, a perovskite-type oxide containing lead and an upper electrode layer. The growth control layer includes a metal oxide represented by MdN1-dOe, where M is composed of one or more metal elements capable of substituting in the perovskite-type oxide, 0<d<1, and when the electronegativity is X, 1.41X?1.05?d?A1·exp(?X/t1)+y0, where A1=1.68×1012, t1=0.0306, and y0=0.59958.

Abstract: Provided are a piezoelectric element having high stability, which operates with high efficiency, and a method for manufacturing the piezoelectric element. The piezoelectric element (10) has a laminate structure in which a first electrode (14), a first piezoelectric film (16), a second electrode (18), an adhesion layer (20), an interlayer (22), a third electrode (24), a second piezoelectric film (26), and a fourth electrode (28) are laminated in this order on a silicon substrate (12). The interlayer (22) is formed of a material different from that of the second electrode (18) and has a thickness of 0.4 ?m to 10 ?m. A device having a diaphragm structure or a cantilever structure is formed by removing a part of the silicon substrate (12). The respective layers (14 to 28) laminated on the silicon substrate (12) can be formed using a thin film formation method represented by a vapor phase epitaxial method.

Abstract: A stethoscope includes a support base; and a detection unit that is supported by the support base and detects a sound generated from an object to be measured, in which the detection unit has a piezoelectric film disposed to face the support base in at least a portion for detecting the sound generated from the object to be measured and convexly curved to a side opposite to the support base, the piezoelectric film includes a piezoelectric layer having two main surfaces facing each other, a first electrode provided on a main surface on a support base side of the two main surfaces, and a second electrode provided on a main surface on a side opposite to the support base, and a strain generated in the piezoelectric film due to the sound generated from the object to be measured is detected as a vibration signal.

Abstract: A piezoelectric element is obtained using a method including: preparing a first structure; preparing a second structure; disposing a first facing electrode layer of the first structure to face a first surface of a vibration plate substrate and bonding the first structure to the first surface of the vibration plate substrate; processing the vibration plate substrate into a vibration plate by polishing or etching a second surface of the vibration plate substrate to which the first structure is bonded; preparing a laminate structure by disposing a second facing electrode layer of the second structure to face an exposed surface of the vibration plate and bonding the second structure to the vibration plate; and removing at least a part of a first silicon substrate of the first structure and a second silicon substrate of the second structure from the laminate structure.

Abstract: Provided is a pyroelectric sensor including: an Si substrate; a laminated portion in which a heat absorption layer formed of an inorganic material, a lower electrode, a piezoelectric film, and an upper electrode are laminated in this order from one surface side of the Si substrate on the one surface; and an optical filter that is provided at a position of the other surface of the Si substrate corresponding to the laminated portion and selectively transmits an infrared ray, in which an infrared ray incident to the laminated portion from the optical filter side through the Si substrate is sensed.

Abstract: A method of manufacturing a power generation element includes a first step of disposing a support unit that supports a vibration unit in one end portion of the vibration unit in one direction, and disposing a weight unit in the other end portion of the vibration unit in the one direction in a substrate including the vibration unit capable of vibrating, a second step of disposing a piezoelectric unit that generates power due to vibration in a portion of the vibration unit on an opposite side from the support unit side in a thickness direction of the substrate after the support unit and the weight unit are disposed in the vibration unit, and a third step of extracting a power generation element from the substrate by cutting an outer edge of the vibration unit in the thickness direction of the substrate after the piezoelectric unit is disposed in the vibration unit.

Abstract: Provided is a pyroelectric sensor including: an Si substrate; a laminated portion in which a heat absorption layer formed of an inorganic material, a lower electrode, a piezoelectric film, and an upper electrode are laminated in this order from one surface side of the Si substrate on the one surface; and an optical filter that is provided at a position of the other surface of the Si substrate corresponding to the laminated portion and selectively transmits an infrared ray, in which an infrared ray incident to the laminated portion from the optical filter side through the Si substrate is sensed.

Abstract: Provided are a piezoelectric element having high stability, which operates with high efficiency, and a method for manufacturing the piezoelectric element. The piezoelectric element (10) has a laminate structure in which a first electrode (14), a first piezoelectric film (16), a second electrode (18), an adhesion layer (20), an interlayer (22), a third electrode (24), a second piezoelectric film (26), and a fourth electrode (28) are laminated in this order on a silicon substrate (12). The interlayer (22) is formed of a material different from that of the second electrode (18) and has a thickness of 0.4 ?m to 10 ?m. A device having a diaphragm structure or a cantilever structure is formed by removing a part of the silicon substrate (12). The respective layers (14 to 28) laminated on the silicon substrate (12) can be formed using a thin film formation method represented by a vapor phase epitaxial method.

Abstract: The piezoelectric film includes a perovskite oxide which is represented by General Formula P, A1+?B1-x-yNbxNiyOz??General Formula P where A contains at least Pb, B contains at least Zr and Ti, and x and y respectively satisfy 0.1?x?0.3 and 0?y?0.75x. Although standard values of ? and z are ?=0 and z=3, these values may deviate from the standard values in a range in which a perovskite structure is capable of being obtained.

Abstract: The piezoelectric film includes a perovskite oxide which is represented by General Formula P, A1+?B1-x-yNbxNiyOz??General Formula P where A contains at least Pb, B contains at least Zr and Ti, and x and y respectively satisfy 0.1?x?0.3 and 0?y?0.75x. Although standard values of ? and z are ?=0 and z=3, these values may deviate from the standard values in a range in which a perovskite structure is capable of being obtained.

Abstract: A piezoelectric film of the present invention is a piezoelectric film including a perovskite oxide represented by the following formula (P), in which crystal phases of the perovskite oxide include tetragonal crystals and rhombohedral crystals at a ratio that satisfies the following formula (1). A1+?[(ZrxTi1?x)1?aNba]Oy??(P) 0.70?rhombohedral crystals/(rhombohedral crystals+tetragonal crystals)?0.95?? (1), where, in the formula (P), A is an A-site element primarily containing Pb, and Zr, Ti, and Nb are B-site elements. x is equal to or higher than 0.4 and lower than 1, excluding x of equal to or higher than 0.51 and equal to or lower than 0.53. a is equal to or higher than 0.08.

Abstract: A piezoelectric element is obtained using a method including: preparing a first structure; preparing a second structure; disposing a first facing electrode layer of the first structure to face a first surface of a vibration plate substrate and bonding the first structure to the first surface of the vibration plate substrate; processing the vibration plate substrate into a vibration plate by polishing or etching a second surface of the vibration plate substrate to which the first structure is bonded; preparing a laminate structure by disposing a second facing electrode layer of the second structure to face an exposed surface of the vibration plate and bonding the second structure to the vibration plate; and removing at least a part of a first silicon substrate of the first structure and a second silicon substrate of the second structure from the laminate structure.

Abstract: A piezoelectric element includes: a titanium-containing adhesion layer, a lower electrode, a PZT-based piezoelectric film, and an upper electrode, which are sequentially provided on a silicon substrate, in which the lower electrode includes a columnar structure film consisting of a large number of columnar crystals which are grown from a surface of the titanium-containing adhesion layer and have a platinum group element as a primary component, and an adhesion layer component diffused from the titanium containing adhesion layer and oxygen diffused from the piezoelectric film side, which are present in the columnar structure film, and a main column diameter of the columnar crystal of the columnar structure film is 50 nm or more and 200 nm or less.

Abstract: A piezoelectric film of the present invention is a piezoelectric film including a perovskite oxide represented by the following formula (P), in which crystal phases of the perovskite oxide include tetragonal crystals and rhombohedral crystals at a ratio that satisfies the following formula (1). A1+?[(ZrxTi1-x)1-aNba]Oy??(P) 0.70?rhombohedral crystals/(rhombohedral crystals+tetragonal crystals)?0.95?? (1), where, in the formula (P), A is an A-site element primarily containing Pb, and Zr, Ti, and Nb are B-site elements. x is equal to or higher than 0.4 and lower than 1, excluding x of equal to or higher than 0.51 and equal to or lower than 0.53. a is equal to or higher than 0.08.

Abstract: In a method for etching a piezoelectric film and a manufacturing method thereof, a piezoelectric film is formed on a substrate on which a lower electrode is formed, a metal film having a thickness of 20 nm to 300 nm is formed, a patterned resist film is formed, the metal film is etched with a first etchant to which the piezoelectric film has etching resistance, and the piezoelectric film is etched with a second etchant to which the metal film has etching resistance.

Abstract: A piezoelectric device, which has bipolar polarization-electric field (Pr-E) hysteresis characteristics of a piezoelectric material asymmetrically biased, when a first and second coercive electric fields respectively having smaller and larger absolute values are defined as Ec1 and Ec2 and a bias ratio of the coercive electric field is defined as [(Ec2+Ec1)/(Ec2?Ec1)]×100[%], includes a piezoelectric element unit including a piezoelectric body film whose bias ratio is 20% or more, the piezoelectric element unit operating with an electric field intensity smaller than that of the first coercive electric field. The piezoelectric device includes a refresh voltage applying circuit configured to apply a voltage to maintain operation performance of the relevant device, the voltage having an electric field intensity larger than the electric field intensity for operating the device and being equal to or less than three times |Ec1|, such that a polarized state of the piezoelectric body film is restored.

Abstract: Provided are a piezoelectric element having high stability, which operates with high efficiency, and a method for manufacturing the piezoelectric element. The piezoelectric element (10) has a laminate structure in which a first electrode (14), a first piezoelectric film (16), a second electrode (18), an adhesion layer (20), an interlayer (22), a third electrode (24), a second piezoelectric film (26), and a fourth electrode (28) are laminated in this order on a silicon substrate (12). The interlayer (22) is formed of a material different from that of the second electrode (18) and has a thickness of 0.4 ?m to 10 ?m. A device having a diaphragm structure or a cantilever structure is formed by removing a part of the silicon substrate (12). The respective layers (14 to 28) laminated on the silicon substrate (12) can be formed using a thin film formation method represented by a vapor phase epitaxial method.

Abstract: There is provided a field effect transistor having, on a substrate, at least a gate electrode, a gate insulating film, an active layer mainly containing an oxide semiconductor that contains at least one of In, Ga or Zn, a source electrode, and a drain electrode, the field effect transistor including: a heat diffusion layer, wherein, given that a thermal conductivity of the substrate is Nsub (W/mK), a thermal conductivity of the heat diffusion layer is Nkaku (W/mK), a film thickness of the heat diffusion layer is T (mm), a planar opening ratio of the heat diffusion layer is R (0?R?1), and S=T×R, the thermal conductivity Nsub of the substrate satisfies the condition Nsub<1.8, and the thermal conductivity Nkaku of the heat diffusion layer satisfies the conditions Nkaku>3.0×S^(?0.97×e^(?1.2×Nsub)) and Nkaku?Nsub.

Abstract: In a method for etching a piezoelectric film and a manufacturing method thereof, a piezoelectric film is formed on a substrate on which a lower electrode is formed, a metal film having a thickness of 20 nm to 300 nm is formed, a patterned resist film is formed, the metal film is etched with a first etchant to which the piezoelectric film has etching resistance, and the piezoelectric film is etched with a second etchant to which the metal film has etching resistance.