Canon Kabushiki Kaisha

National Institute of Advanced Industrial Science and Technology

University of Yamanashi

Kyoto University

Tokyo Institute of Technology

Tokyo University of Science Educational Foundation Administrative Organization

Sophia University

Ngk Spark Plug Company, Limited

The Circle for the Promotion of Science and Engineering

Takashi Iijima

Hiroshi Funakubo

Nobuhiro Kumada

Satoshi Wada

Masaki Azuma

Makoto Kubota

Toshihiro Ifuku

Bong-Yeon Lee

Soichiro Okamura

Takayuki Watanabe

Kaoru Miura

Hiroshi Uchida

Jumpei Hayashi

Kenji Takashima

Keisuke Yamato

Takanori Matsuda

Yoshitaka Nakamura

Yuichi Shimakawa

Olga Alexandrovna Smirnova

Kenichi Takeda

Tatsuo Furuta

Zuyi Zhang

Takeshi Morita

Shintaro Yokoyama

Keisuke Yazawa

Hirofumi Matsuda

Kang Chen

Takasuke Irie

An ultrasonic generator includes an ultrasonic wave source and a converging portion. The converging portion includes a first reflecting portion which reflects the ultrasonic wave generated by the ultrasonic wave source on its first reflecting surface, a second reflecting portion which reflects the ultrasonic wave reflected by the first reflecting surface on its second reflecting surface, and a waveguide serving as a transmission path for the ultrasonic wave. The waveguide is disposed such that the ultrasonic wave reflected by the second reflecting surface is introduced through an introduction portion thereof. The focal point of the second reflecting surface and the focal point of the first reflecting surface are disposed such that the ultrasonic wave reflected by the second reflecting surface becomes a plane wave.

Ultrasonic generator

Provided is a piezoelectric material excellent in piezoelectricity. The piezoelectric material includes a perovskite-type complex oxide represented by the following General Formula (1).A(ZnTi)MO&#x2003;&#x2003;(1)wherein A represents at least one kind of element containing at least a Bi element and selected from a trivalent metal element; M represents at least one kind of element of Fe, Al, Sc, Mn, Y, Ga, and Yb; x represents a numerical value satisfying 0.4&#x2266;x&#x2266;0.6; and y represents a numerical value satisfying 0.1&#x2266;y&#x2266;0.9.

Metal oxide

Provided are a bismuth-based piezoelectric material whose insulation property is improved while its performance as a piezoelectric body is not impaired and a piezoelectric device using the piezoelectric material. The piezoelectric material includes a perovskite-type metal oxide represented by the following general formula (1):Bi(FeCo)O&#x2003;&#x2003;(1)where 0.95&#x2266;x&#x2266;1.25 and 0&#x2266;y&#x2266;0.30, and a root mean square roughness Rq (nm) of a surface of the piezoelectric material satisfies a relationship of 0&#x3c;Rq&#x2266;25y+2 (0&#x2266;y&#x2266;0.30).

Method of producing piezoelectric device using Be, Fe and Co under excess oxygen atmosphere

Provided is a piezoelectric material having a high Curie temperature and satisfactory piezoelectric characteristics, the piezoelectric material being represented by the following general formula (1):A(ZnTi)MO&#x2003;&#x2003;(1)where A represents a Bi element, M represents at least one element selected from Fe, Al, Sc, Mn, Y, Ga, and Yb; x represents a numerical value of 0.4&#x2266;x&#x2266;0.6; and y represents a numerical value of 0.17&#x2266;y&#x2266;0.60.

Piezoelectric material

Provided is a piezoelectric material which includes a compound free of lead and alkali metal and has a good piezoelectric property. The piezoelectric material where tungsten bronze structure oxides being free of lead and alkali metal and represented by ABOand A'B&#x2032;Oare combined to form a morphotropic phase boundary has good piezoelectric property. The ABOis b(BaBiNbO)+(1&#x2212;b)(BaAgNbO) (0&#x2266;b&#x2266;1 and 0&#x3c;&#x3b1;&#x2266;0.4), and the A&#x2032;B&#x2032;Ois c(SrNbO)+d(CaNbO)+e(BaNbO) (0&#x2266;c&#x2266;0.8, 0&#x2266;d&#x2266;0.4, 0.1&#x2266;e&#x2266;0.9, and c+d+e=1).

Provided is a piezoelectric material having good piezoelectric properties and a Curie temperature (Tc) of 150&#xb0; C. or higher, and a piezoelectric device using the piezoelectric material. The piezoelectric material includes a sintered body made of a perovskite-type metal oxide represented by the following general formula (1): xBi(MgTi)O-(1-x)BaTiO(1), where x satisfies 0.17&#x2266;x&#x2266;0.8, in which an average grain size of grains contained in the sintered body is 0.5 &#x3bc;m or larger to 10 &#x3bc;m or smaller, and the sintered body is polycrystalline. In addition, the piezoelectric device includes a piezoelectric material and a pair of electrodes disposed in contact with the piezoelectric material, in which the piezoelectric material is the above-mentioned piezoelectric material.

Piezoelectric material, method of manufacturing the same, and piezoelectric device

Provided are a bismuth-based piezoelectric material whose insulation property is improved while its performance as a piezoelectric body is not impaired, and a piezoelectric device using the piezoelectric material. The piezoelectric material includes a perovskite-type metal oxide represented by the following general formula (1):Bi(FeCo)O&#x2003;&#x2003;(1)where 0.95&#x2266;x&#x2266;1.25 and 0&#x2266;y&#x2266;0.30, and a root mean square roughness Rq (nm) of a surface of the piezoelectric material satisfies a relationship of 0&#x3c;Rq&#x2266;25y+2 (0&#x2266;y&#x2266;0.30).

Piezoelectric material, piezoelectric device, and method of producing the piezoelectric device

Provided is a piezoelectric material having good piezoelectric properties and a Curie temperature (Tc) of 150&#xb0; C. or higher, and a piezoelectric device using the piezoelectric material. The piezoelectric material includes a sintered body made of a perovskite-type metal oxide represented by the following general formula (1):Bi(MgTi)O-(1-)BaTiO&#x2003;&#x2003;(1),where x satisfies 0.17&#x2266;x&#x2266;0.8, in which an average grain size of grains contained in the sintered body is 0.5 &#x3bc;m or larger to 10 &#x3bc;m or smaller, and the sintered body is polycrystalline. In addition, the piezoelectric device includes a piezoelectric material and a pair of electrodes disposed in contact with the piezoelectric material, in which the piezoelectric material is the above-mentioned piezoelectric material.

Provided is a piezoelectric material including a lead-free perovskite-type composite oxide which is excellent in piezoelectric characteristics and temperature characteristics and is represented by the general formula (1):ABO-A'BO-A&#x2033;B&#x2032;Oin which A is a Bi element; A&#x2032; is a rare earth element including La; B is at least one element selected from Ti, Zn, Sn and Zr; A&#x2033; is at least one element selected from Ba, Sr and Ca; B&#x2032; is at least one element selected from divalent, trivalent, pentavalent, tetravalent, and hexavalent elements; and x is a value of 0.10 or more and 0.95 or less, y is a value of 0 or more and 0.5 or less, and z is a value of 0 or more and 0.7 or less, provided that x+y+z=1.

An oxynitride piezoelectric material, which exhibits ferroelectricity and has good piezoelectric properties, and a method of producing the oxynitride piezoelectric material. The oxynitride piezoelectric material includes a tetragonal perovskite-type oxynitride represented by the following general formula (1):ABiBB'ON&#x2003;&#x2003;(1),where A represents a divalent element, B and B&#x2032; each represent a tetravalent element, x represents a numerical value of 0.35 or more to 0.6 or less, y represents a numerical value of 0.35 or more to 0.6 or less, z represents a numerical value of 0.35 or more to 0.6 or less, and &#x3b4;1 and &#x3b4;2 each represent a numerical value of &#x2212;0.2 or more to 0.2 or less, in which the A includes at least one kind selected from Ba, Sr, and Ca and the B and the B&#x2032; each include at least one kind selected from Ti, Zr, Hf, Si, Ge, and Sn.

Oxynitride piezoelectric material and method of producing the same

Provided are a piezoelectric material without using lead or an alkali metal, the piezoelectric material having a stable crystal structure in a wide temperature range, high insulation property, and high piezoelectric property, and a piezoelectric element using the piezoelectric material, in which the piezoelectric material is made of a metal oxide having a tetragonal crystal structure and expressed by Ba(SiGeTi)O(here, 0&#x2266;x&#x2266;1, 0&#x2266;y&#x2266;1, and 0&#x2266;z&#x2266;0.5), the piezoelectric element includes the piezoelectric material and a pair of electrodes sandwiching the piezoelectric material, and at least one of the pair of electrodes is made of SrRuOor Ni.

Metal oxide, piezoelectric material and piezoelectric element

A lead zirconate titanate-based thin film is an epitaxial crystal thin film and has a chemical composition represented by the general formula PbLnZrTiO(wherein Ln represents any one selected from the group consisting of lanthanum, lanthanoid elements, niobium, calcium, barium, strontium, iron, manganese and tin; and 0&#x2266;x&#x3c;1, 0.43&#x2266;y&#x2266;0.65) and whose orientation is {111} (including orientations whose tilt angle from the direction perpendicular to the substrate surface is within 15&#xb0;).

Growing community of inventors

Tsukuba, Japan

Takashi Iijima