Abstract: A semiconductor ceramic composition which is a BaTiO3 based semiconductor ceramic composition, wherein, part of Ba is replaced by at least A (at least one alkali metal element selected from Na and K), Bi and RE (at least one element selected from rare earth elements including Y), and part of Ti is replaced by at least TM (at least one element selected from the group including of V, Nb and Ta), the relationships of 0.7?{(the content of Bi)/(the content of A)}?1.43, 0.017?{(the content of Bi)+(the content of A)}?0.25, and 0<{(the content of RE)+(the content of TM)}?0.01 are satisfied when the total content of Ti and TM is set as 1 mol, the grain sizes have a maximum peak in a grain size distribution in a range of 1.1 ?m to 4.0 ?m or less, and the distribution frequency of the peak is 20% or more.

Abstract: A semiconductor ceramic composition represented by formula (1), (BavBixAyREw)m(TiuTMz)O3??(1), wherein, A represents at least one element selected from Na and K, RE represents at least one element selected from Y, La, Ce, Pr, Nd, Sm, Gd, Dy and Er; 0.750y?x?1.50y??(2), 0.007?y?0.125??(3), 0?(w+z)?0.010??(4), v+x+y+w=1??(5), u+z=1??(6), 0.950?m?1.050??(7), 0.001 to 0.055 mol of Ca is contained, and 0.0005 to 0.005 mol of at least one selected from Mg, Al, Fe, Co, Cu and Zn is contained.

Abstract: An object of the present invention is to provide a method for producing an electromagnetic wave absorbing sheet with properties thereof further improved. A treated powder P0 pulverized and flaked in a pulverizing step is placed in a centrifugal gas-flow classifier 50. The treated powder is classified into a flaky soft magnetic metal powder P1 and a non-flaky powder P2 on the basis of the difference between the centrifugal force and the drag acting on each of these powders in a gas flow circling in a chamber 51. The non-flaky powder P2 is eliminated and the flaky soft magnetic metal powder P1 is used to form an electromagnetic wave absorbing sheet, the performances of the electromagnetic wave absorbing sheet being thereby improved. The classified non-flaky powder P2 is preferably recycled as the raw material powder used in the pulverizing step.

Abstract: A magnetic garnet single crystal film formation substrate for growing a magnetic garnet single crystal film by liquid phase epitaxial growth is provided. This substrate comprises a base substrate composed of a garnet-based single crystal which is unstable with a flux used for the liquid phase epitaxial growth and a buffer layer composed of a garnet-based single crystal thin film formed on the base substrate and being stable with said flux. A high-quality magnetic garnet single crystal film can be produced by using the substrate. The magnetic garnet single crystal film is used as an optical element, such as a Faraday element, used in an optical isolator, optical circulator and magneto-optical sensor, etc.

Abstract: A compact and wide band surface acoustic wave device for intermediate-frequency is disclosed. A piezoelectric substrate for use in a surface acoustic wave device having high electromechanical coupling factor and low SAW velocity is also disclosed. The surface acoustic wave device is constituted of a piezoelectric substrate 1 and inter-digital electrodes 2, 2 formed on the piezoelectric substrate 1. The piezoelectric substrate 1 has a crystal structure of Ca3Ga2Ge4O14 and is represented by the chemical formula, Ca3TaGa3Si2O14. A cut angle of the piezoelectric substrate 1 cut out of the single crystal and a direction of propagation of surface acoustic waves on the piezoelectric substrate represented in terms of Euler's angles (&phgr;, &thgr;, &psgr;) are found in an area represented by −2.5°≦&phgr;≦2.5°, 30°≦&thgr;≦90°, and −65°≦&psgr;≦65°.

Abstract: The surface acoustic wave device comprises a piezoelectric substrate (1) and a pair of interdigitated electrodes (2) provided on one main surface of the piezoelectric substrate (1). As the material of the piezoelectric substrate (1), a single crystal belonging to the point group 32, having a crystal structure of Ca3Ga2Ge4O14 type, containing Ca, Nb, Ga, Si and O as main components, and being represented by the chemical formula Ca3NbGa3Si2O14 is used. The cut angle of the substrate (1) and the propagation direction can be selected as appropriate to thereby realize the substrate (1) which has a large electromechanical coupling coefficient that is effective to achieve a wider passband and a low SAW velocity that is effective to reduce the size of a surface acoustic wave device.

Abstract: A compact and wide band surface acoustic wave device for intermediate-frequency is disclosed. A piezoelectric substrate for use in a surface acoustic wave device having high electromechanical coupling factor and low SAW velocity is also disclosed.

Abstract: An object of the invention is to achieve a wider passband and reduction in size of a surface acoustic wave device.

Abstract: A compact and wide band surface acoustic wave device for intermediate-frequency is disclosed. A piezoelectric substrate for use in a surface acoustic wave device having high electromechanical coupling factor and low SAW velocity is also disclosed. The surface acoustic wave device is constituted of a piezoelectric substrate 1 and inter-digital electrodes 2, 2 formed on the piezoelectric substrate 1. The piezoelectric substrate 1 has a crystal structure of Ca3Ga2Ge4O14 and is represented by the chemical formula, Sr3NbGa3Si2O14.

Abstract: A surface acoustic wave device includes a substrate and an inter-digital electrode on a surface of the substrate, wherein the substrate is formed by cutting out of a single crystal represented by a chemical formula, La&agr;Ta&bgr;Ga&ggr;O&dgr;(2.9≦&agr;≦3.1, 0.48≦&bgr;≦0.52, 5.4≦&ggr;≦5.

Abstract: The present invention provides a piezoelectric substrate for a surface acoustic wave device which has high electromechanical coupling coefficient and low SAW velocity, and a surface acoustic wave device using the same. The present invention applies a single crystal comprising belonging to a point group 32 and having Ca3Ga2Ge4O14 type crystal structure. The basic component of the single crystal is comprised of La, Sr, Ta, Ga and O and is represented by the chemical formula: La3−xSrxTa0.5+0.5xGa5.5−0.5xO14. The composition ratio of Sr is preferably in the range of 0 x≦0.15, and more preferably in the range of 0.07 x≦0.08. The present invention also provides a surface acoustic wave device using that in which an interdigital finger electrode is formed in one main surface of the aforementioned piezoelectric substrate.

Abstract: A compact and wide band surface acoustic wave device for intermediate-frequency is disclosed. A piezoelectric substrate for use in a surface acoustic wave device having high electromechanical coupling factor and low SAW velocity is also disclosed.

Abstract: A surface acoustic wave device has a piezoelectric substrate whose properties include electromechanical coupling coefficient advantageous to widening passband width and SAW velocity advantageous to achieving a compact surface acoustic wave device. The piezoelectric substrate is composed of the single crystal represented by chemical formula Sr3TaGa3Si2O14 belonging to point group 32. For example, cut angle of the single crystal and propagation direction of the surface acoustic wave are in region 1-1, wherein said region 1-1 represented by Euler angles (&phgr;, &thgr;, &psgr;) satisfies &phgr;=25° ˜35°, &thgr;=20° ˜90°, &psgr;=−40° ˜40°. These angles may be in range 1-2, wherein said range 1-2 satisfies &phgr;=25° ˜35°, &thgr;=20° ˜90°, &psgr;=−25° ˜25°.