摘要:
A multi-component material is represented by the general formula (I): Ba(1−y−y)PbyMxTiO3 (I) in which: M is Sr or Cd; x is the decimal fraction molar concentration of MTiO3, where x has a value equal to or greater than about 0.20 and less than or equal to about 0.75; and y is the decimal fraction molar concentration of PbTiO3, where y has a value greater than zero and less than or equal to about 0.40, and x+y is less than 1.0. In addition, a method of graphically estimating the composition of the multi-component material represented by the general formula (I) is disclosed herein. In a preferred embodiment, x has a value between about 0.28 and 0.66, and y has value greater than zero and less than or equal to about 0.34, while said material has a Curie point temperature of about 25° C. or room temperature. These room temperature Curie point materials are useful in uncooled thermal imaging applications.
摘要:
A thermally stable, piezoelectric and pyroelectric polymeric substrate was prepared. This thermally stable, piezoelectric and pyroelectric polymeric substrate may be used to prepare electromechanical transducers, thermomechanical transducers, accelerometers, acoustic sensors, infrared sensors, pressure sensors, vibration sensors, impact sensors, in-situ temperature sensors, in-situ stress/strain sensors, micro actuators, switches, adjustable fresnel lenses, speakers, tactile sensors, weather sensors, micro positioners, ultrasonic devices, power generators, tunable reflectors, microphones, and hydrophones. The process for preparing these polymeric substrates includes: providing a polymeric substrate having a softening temperature greater than 100° C.; depositing a metal electrode material onto the polymer film; attaching a plurality of electrical leads to the metal electrode coated polymeric substrate; heating the metal electrode coated polymeric substrate in a low dielectric medium; applying a voltage to the heated metal electrode coated polymeric substrate to induce polarization; and cooling the polarized metal electrode coated polymeric electrode while maintaining a constant voltage.
摘要:
A ferroelectric thin film includes lead titanate including La and at least an element which forms a six-coordinate bond with oxygen atoms and which is selected from the group consisting of Mg and Mn. The ferroelectric thin film is imparted with a high c-axis orientation while the film is formed without a polarization process. The ferroelectric thin film is manufactured by the steps of: positioning a MgO single crystal substrate disposed in advance with a foundation platinum electrode by a sputtering method on the surface of a substrate heater, exhausting a chamber, heating the substrate by a substrate heater, letting in sputtering gases Ar and O.sub.2 through a nozzle into the chamber, and maintaining a high degree of vacuum. Then, high frequency electric power is input to a target from a high frequency electric power source to generate plasma, and a film is formed on the substrate. In this way, a ferroelectric thin film containing, for example, �(1-x).multidot.Pb.sub.1-y La.sub.y Ti.sub.1-y/4 O.sub.3 +x.multidot.MgO!, where x=0.01.about.0.10 and y=0.05.about.0.25 can be manufactured.
摘要:
A method whereby perovskite type oxide dielectric thin films with ABO.sub.3 structure are able to be formed with such features as good stability, uniformity, reproducibility, or the like, with high through-put by having a deposition process, wherein the thin films are deposited on a substrate, and a stabilization process, where no deposition of the thin films takes place, repeated alternatingly while the substrate temperature being kept near the temperature at which perovskite type oxide dielectric thin films are formed. Also, by employing (i) a processing method wherein a decomposing excitation of a reactive gas due to plasma takes place on or near the deposition surface in a gaseous atmosphere comprising a gas that reacts with the elements composing the thin films, (ii) a processing method wherein an oxidation reaction takes place on the deposition surface in a gaseous atmosphere comprising at least ozone (O.sub.3), and (iii) a processing method wherein light of short wave length is irradiated on the deposition surface in a gaseous atmosphere comprising at least reactive elements in the non-deposition process, the oxygen concentration in the deposited thin films is adjusted and dielectric thin films of good quality and an extremely low defect content are realized.
摘要:
A radiation detector having a radiation detection element of a pyroelectric ceramic material on the basis of lead titanate, the composition of which corresponds to the formula Pb.sub.1-(x+0.5(x-y)) RE.sub.x (Ti.sub.1-y Mn.sub.y)O.sub.3, where RE is at least one rare earth metal and 0.04.ltoreq.x.ltoreq.0.20 and 0.01.ltoreq.y.ltoreq.0.04. The element is disposed within a windowed housing.
摘要:
For applying ferroelectrics to electronic devices, the poling treatment of the ferroelectrics has been necessary in order to uniform directions of spontaneous polarizations, Ps, in each ferroelectric. This treatment brings about (1) low yields of the devices, (2) difficulties in the fabrication of array devices, and (3) difficulties in the formation of ferroelectric films on semiconductor devices. Now it has been found that a self-polarized film in which spontaneous polarizations, Ps, are unidirectional can be formed by sputtering a ferroelectric materials containing lead under such conditions that the orientation of Ps will be controlled without poling treatment and a high-performance ferroelectric device can be obtained in a high yield by using this film, and thus a process for producing such devices has been found.
摘要:
This invention relates to a method for electric field orientation of liquid crystal polymers and oriented materials of liquid crystal polymers obtained by the method. This electric field orientation method comprises applying a pulsating electric field which is predominantly unidirectional and whose magnitude is varying periodically or non-periodically to a liquid crystal polymer capable of forming an optically anisotropic melt phase. The oriented material of liquid crystal polymer thus obtained has been unidirectionally oriented and polarized. This oriented, polarized material of liquid crystal polymer can be utilized as a piezoelectric material, pyroelectric material, electret material, non-linear optical element or the like.
摘要:
Langmuir-Blodgett(LB) films of ABAB structure in which the compounds A and B are different and contain complementary groups which result in non-centrosymmetry of the layer plane. Three types of structures are described: (1) in which A and B have similar backbones with complementary chromophore groups, (2) in which A and B have similar backbones with complementary functional groups, and (3) in which A and B have related functional groups but complementary backbones.
摘要:
A polymer pyroelectric infrared sensor having an improved sensitivity and an improved heat resistance is formed by disposing a pyroelectric film having electrodes for taking out a pyroelectric output on both sides so as to face a window for introducing infrared rays. The pyroelectric film comprises a pyroelectric film of vinylidene fluoride copolymer having a crystallinity of 60% or more and a relative dielectric constant of 10 or below at 25.degree. C. and in a low frequency region of 0.1-10 Hz.
摘要:
A pyroelectric and isotropic piezoelectric polymeric film, the film being formed from a blend of polyvinylidene fluoride and at least one polymer miscible therewith at a temperature above the melting point of the polyvinylidene fluoride, and a process for preparing the film comprising forming the film, heating it to a temperature sufficient to render the film substantially amorphous, cooling at a rate and to a temperature sufficient to prevent crystallization, and polarizing the film to render same pyroelectric and isotropically piezoelectric.