Abstract: A novel highly bright mechanoluminescence material free from decay of luminescence brightness even if repeated stress is applied, comprising a composite semiconductor crystal of the general formula xM1A1·(1?x)M2A2 (wherein each of M1 and M2 independently represents an atom selected from among Zn, Mn, Cd, Cu, Eu, Fe, Co, Ni, Mg and Ca, and each of A1 and A2 is an atom independently selected from among chalcogens, provided that M1A1 is different from M2A2; and x is a positive number less than 1); and a process for producing the same.

Abstract: A thin film bulk acoustic resonator comprises a substrate (12) of a silicon single crystal, a base film (13) formed on the substrate (12) and composed of a dielectric film mainly containing silicon oxide, and a piezoelectric stacked structure (14) formed on the base film (13). A vibratory section (21) composed of a part of the base film (13) and a part of the piezoelectric stacked structure (14). The piezoelectric stacked structure (14) includes a lower electrode (15), a piezoelectric film (16), and an upper electrode (17) formed in this order from below. The substrate (12) had a via hole (20) in the region corresponding to the vibratory section (21). The via hole forms a space for allowing vibration of the vibratory section (21). The piezoelectric film (16) is an aluminum nitride thin film containing 0.2 to 3.0 atom % of alkaline earth metal and/or a rare earth metal.

Abstract: A thin pressure sensor includes: a pair of external electrodes, which are respectively made of conductive thin films that are respectively provided with piezoelectric layers on inner sides; and a single internal electrode, made of a conductive thin film, which is sealed between the pair of external electrodes, one of the pair of external electrodes having a conducting window that conducts to said internal electrode. The thin pressure sensor has a simple and thin structure with sufficient durability and mechanical strength.

Abstract: A thin film bulk acoustic resonator comprises a substrate (12) of a silicon single crystal, a base film (13) formed on the substrate (12) and composed of a dielectric film mainly containing silicon oxide, and a piezoelectric stacked structure (14) formed on the base film (13). A vibratory section (21) composed of a part of the base film (13) and a part of the piezoelectric stacked structure (14). The piezoelectric stacked structure (14) includes a lower electrode (15), a piezoelectric film (16), and an upper electrode (17) formed in this order from below. The substrate (12) had a via hole (20) in the region corresponding to the vibratory section (21). The via hole forms a space for allowing vibration of the vibratory section (21). The piezoelectric film (16) is an aluminum nitride thin film containing 0.2 to 3.0 atom % of alkaline earth metal and/or a rare earth metal.

Abstract: This invention is to provide a method and a system which, by making use of a stress luminescent material, renders it possible to directly observe a stress distribution on the base of a real time without electrical contacts, and to easily measure a stress or a stress distribution and a stress image. Essentially, the invention comprises the steps of adding a stress to a tested body containing a stress luminescent material whose light emission is proportional to the stress, making visually observable a stress distribution over the tested body in accordance with a luminous intensity of the stress luminescent material contained in the tested body, measuring the luminous intensity of the luminescent material of the tested body, comparing the measured value of the luminous intensity with certain correlation data indicating a relationship between the luminous intensity of the stress luminescent material and a stress, thereby obtaining a stress value or a stress distribution over the tested body.

Abstract: Disclosed is a high-sensitivity flexible ceramic sensor for detecting mechanical shocks and vibrations, which comprises a metal foil of a specified thickness as a substrate, a single-crystalline thin film of a piezoelectric ceramic material such as aluminum nitride and zinc oxide having a specified thickness formed on the substrate, a metallic electrode formed on the thin ceramic film and an external circuit connecting the metal foil and the electrode with insertion of an electric meter for measuring the piezoelectric voltage changes induced in the ceramic thin film.

Abstract: A pressure sensor is formed by sandwiching a pressure-sensitive dielectric membrane between and in contact with a pair of electrodes. As pressure is applied, the dielectric constant of the pressure-sensitive membrane changes while the distance of separation between the pair of electrodes remains constant. This change in the dielectric constant is detected by a circuit as a change in the electrostatic capacitance between the electrodes to measure the applied pressure. Since the pressure-sensitive dielectric membrane is not required to undergo any elastic deformation for measuring the pressure, the pressure sensor can be made extremely thin.

Abstract: A mechanoluminescence material of the present invention is produced by adding a luminescence center to a mother body material, wherein: said mother body material is constituted of at least one kind of oxide selected from alumino silicate, aluminate, silicate, tantalate, niobate, gallium oxide, and ZrO2, and said luminescence center is at least one kind selected from a rare earth metal and a transition metal which emits light when electrons excited by mechanical energy are restored to a normal state.

Abstract: A thin pressure sensor includes: a pair of external electrodes, which are respectively made of conductive thin films that are respectively provided with piezoelectric layers on inner sides; and a single internal electrode, made of a conductive thin film, which is sealed between the pair of external electrodes, one of the pair of external electrodes having a conducting window that conducts to said internal electrode. The thin pressure sensor has a simple and thin structure with sufficient durability and mechanical strength.

Abstract: Disclosed is an electronic device having a multilayered structure consisting of (a) a substrate, (b) an electroconductive layer of lanthanum nickel oxide LaNiO3 having a perovskite structure formed on the substrate surface and (c) a dielectric layer of PZT having an oriented perovskite structure formed on the electroconductive layer. The device exhibits excellent piezoelectric effect under mechanical stress and stable hysteresis phenomenon of electric polarization under application of electric fields so that the device is useful as a stress sensor and as a memory device. A method for the preparation of the multilayered device is disclosed.

Abstract: The invention discloses a method for fine control of the flow rate of a liquid by a microvalve device without using any mechanical structures. The method comprises, while passing the liquid through a flow channel penetrating a substrate of a heat-insulating material, the temperature of the liquid in the flow channel is decreased below the freezing point of the liquid by a temperature-controlling means such as a Peltier element facing the flow channel to close the flow channel by the solidified liquid and the temperature of the solidified liquid is increased above the melting point thereof to cause thawing of the solid resulting in re-opening of the flow channel.

Abstract: Disclosed is a high-sensitivity flexible ceramic sensor for detecting mechanical shocks and vibrations, which comprises a metal foil of a specified thickness as a substrate, a single-crystalline thin film of a piezoelectric ceramic material such as aluminum nitride and zinc oxide having a specified thickness formed on the substrate, a metallic electrode formed on the thin ceramic film and an external circuit connecting the metal foil and the electrode with insertion of an electric meter for measuring the piezoelectric voltage changes induced in the ceramic thin film.

Abstract: The invention discloses a method for fine control of the flow rate of a liquid by a microvalve device without using any mechanical structures. The method comprises, while passing the liquid through a flow channel penetrating a substrate of a heat-insulating material, the temperature of the liquid in the flow channel is decreased below the freezing point of the liquid by a temperature-controlling means such as a Peltier element facing the flow channel to close the flow channel by the solidified liquid and the temperature of the solidified liquid is increased above the melting point thereof to cause thawing of the solid resulting in re-opening of the flow channel.

Abstract: A pressure sensor is formed by sandwiching a pressure-sensitive dielectric membrane between and in contact with a pair of electrodes. As pressure is applied, the dielectric constant of the pressure-sensitive membrane changes while the distance of separation between the pair of electrodes remains constant. This change in the dielectric constant is detected by a circuit as a change in the electrostatic capacitance between the electrodes to measure the applied pressure. Since the pressure-sensitive dielectric membrane is not required to undergo any elastic deformation for measuring the pressure, the pressure sensor can be made extremely thin.

Abstract: Disclosed is a high-sensitivity flexible ceramic sensor for detecting mechanical shocks and vibrations, which comprises a metal foil of a specified thickness as a substrate, a single-crystalline thin film of a piezoelectric ceramic material such as aluminum nitride and zinc oxide having a specified thickness formed on the substrate, a metallic electrode formed on the thin ceramic film and an external circuit connecting the metal foil and the electrode with insertion of an electric meter for measuring the piezoelectric voltage changes induced in the ceramic thin film.

Abstract: This invention is to provide a method and a system which, by making use of a stress luminescent material, renders it possible to directly observe a stress distribution on the base of a real time without electrical contacts, and to easily measure a stress or a stress distribution and a stress image. Essentially, the invention comprises the steps of adding a stress to a tested body containing a stress luminescent material whose light emission is proportional to the stress, making visually observable a stress distribution over the tested body in accordance with a luminous intensity of the stress luminescent material contained in the tested body, measuring the luminous intensity of the luminescent material of the tested body, comparing the measured value of the luminous intensity with certain correlation data indicating a relationship between the luminous intensity of the stress luminescent material and a stress, thereby obtaining a stress value or a stress distribution over the tested body.

Abstract: Disclosed is a high-efficiency stress-luminescent material capable of emitting luminescence by receiving a mechanical stress such as compression, shearing and rubbing. The stress-luminescent material is an alkaline earth aluminate of a non-stoichiometric composition deficient in the content of the alkaline earth element by 0.01 to 20% by moles from stoichiometry. The efficiency of stress-luminescence emission can be further enhanced when the non-stoichiometric alkaline earth aluminate contains 0.01 to 10% by moles of rare earth metal ions or transition metal ions. The stress-luminescent material is prepared by subjecting a non-stoichiometric composite oxide of aluminum oxide and an alkaline earth oxide to a calcination treatment at 800 to 1700° C. in a reducing atmosphere.

Abstract: A two-layer structure composite material, by which it is possible to easily detect the occurrence of the cracks occurred in the structural material and to predict the possible destruction of the structural material before it actually occurs. To a structural material, a voltage generating material consisting of a ferroelectric material, a pyroelectric material or a piezoelectric material, is bonded to produce a two-layer structure material, and an electrode is provided for detecting voltage, which is generated owing to impact force.

Abstract: The present invention provides a new stress emission material that is different from the other known materials and that efficiently emits light when subjected to a mechanical external force such as a frictional force, a shear force, an impact, or a pressure. This stress emission material is configured by adding an emission center comprising one or more rare earths or transition metals that emit light when electrons excited by a mechanical force return to their normal state, to a base material comprising one or more of an oxide, a sulfide, a carbide, and a nitride each having an FeS.sub.2 structure. This material has an emission intensity that depends on stress.

Abstract: Provided by the invention is a novel synthetic inorganic triboluminescent material in the form of a powder, sintered block or thin film, of which the matrix phase is a piezoelectric crystalline material of a wurtzite structure such as zinc sulfide and the activator to serve as the center of luminescence is a transition metal element such as manganese, copper and rare earth elements in an amount of 0.01 to 10% by weight. The triboluminescent material is prepared by subjecting a powder blend of the matrix phase material and a thermally decomposable compound of the activator element first to a preparatory calcination treatment at 500 to 800.degree. C. and then, preferably in the form of a powder compact, to a second calcination treatment at 900 to 1700.degree. C., preferably, in vacuum under a sealed condition, when the material is liable to cause sublimation, or in an atmosphere of a reducing gas.