Abstract: There are provided a piezoelectric body of ytterbium-doped aluminum nitride, having a greater piezoelectric coefficient d33 or g33 than those not doped with ytterbium, and a MEMS device using the piezoelectric body. The piezoelectric body is represented by a chemical formula Al1-xYbxN where a value of x is more than 0 and less than 0.37 and having a lattice constant ratio c/a in a range of 1.53 or more and less than 1.6. The piezoelectric body with such a configuration has a greater piezoelectric coefficient d33 or g33 than those not doped with ytterbium.

Abstract: Provided is a scandium-doped aluminum nitride with nitrogen polarity. The nitride material is represented by the chemical formula ScXMYAl1-X-YN. M is at least one or more elements among C, Si, Ge, and Sn, X is greater than 0 and not greater than 0.4, Y is greater than 0 and not greater than 0.2, and X/Y is less than or equal to 5. The nitride material has piezoelectricity with a polarization direction of nitrogen polarity opposite to the direction of thin film growth.

Abstract: A gallium nitride structure that includes: a substrate; a gallium nitride layer opposed to the substrate and containing gallium nitride as a main component thereof; and a first electrode between the gallium nitride layer and the substrate. The first electrode includes at least one hafnium layer containing a single metal of hafnium as a main component thereof, and the at least one hafnium layer is in contact with the gallium nitride layer.

Abstract: Provide are a nitride piezoelectric body having a value indicating a performance index (at least any one of d33, g33, and K2) higher than that of aluminum nitride not doped with any element, and a MEMS device using the same. The nitride piezoelectric body is a piezoelectric body represented by chemical formula Al1-X-YMgXTaYN, wherein X+Y is less than 1, X is in a range of more than 0 and less than 1, and Y is in a range of more than 0 and less than 1, and Ta includes tetravalent tantalum.

Abstract: An object is to provide a piezoelectric body having a value indicating a higher performance index (d33, e33, C33, g33, and/or k2) than aluminum nitride not doped with any element. The piezoelectric body is represented by a chemical formula Al1-X-YMgXMYN where X+Y is less than 1, X is in a range of more than 0 and less than 1, and Y is in a range of more than 0 and less than 1.

Abstract: There are provided a piezoelectric body of ytterbium-doped aluminum nitride, having a greater piezoelectric coefficient d33 or g33 than those not doped with ytterbium, and a MEMS device using the piezoelectric body. The piezoelectric body is represented by a chemical formula Al1-xYbxN where a value of x is more than 0 and less than 0.37 and having a lattice constant ratio c/a in a range of 1.53 or more and less than 1.6. The piezoelectric body with such a configuration has a greater piezoelectric coefficient d33 or g33 than those not doped with ytterbium.

Abstract: A piezoelectric thin film composed of aluminum nitride and which contains magnesium and 31 to 120 atomic percent of niobium relative to 100 atomic percent of the magnesium, and the total content of the magnesium and the niobium relative to the total sum of contents of the magnesium, the niobium and the aluminum nitride falls within the range of 10 to 67 atomic percent.

Abstract: A germanium-containing aluminum nitride piezoelectric film and a method for manufacturing an aluminum nitride piezoelectric film in which a germanium-containing aluminum nitride piezoelectric film is grown on a substrate by sputtering.

Abstract: A gallium nitride structure that includes: a substrate; a gallium nitride layer opposed to the substrate and containing gallium nitride as a main component thereof; and a first electrode between the gallium nitride layer and the substrate. The first electrode includes at least one hafnium layer containing a single metal of hafnium as a main component thereof, and the at least one hafnium layer is in contact with the gallium nitride layer.

Abstract: A piezoelectric thin film comprising aluminum nitride containing magnesium and hafnium, wherein a content of the hafnium based on 100 atomic % of the magnesium is 8 atomic % or more and less than 100 atomic %, and a total content of the magnesium and hafnium based on a sum of a content of the magnesium, hafnium, and aluminum is in a range of 47 atomic % or less.

Abstract: A piezoelectric member that achieves a high sound speed includes a silicon-containing substrate and a piezoelectric layer. The piezoelectric layer is disposed on the silicon-containing substrate. At least a surface layer of the piezoelectric layer on a side opposite to the silicon-containing substrate is made of BxAl1-xN (0<x?0.2).

Abstract: A piezoelectric thin film is formed through sputtering and consists essentially of scandium aluminum nitride. The carbon atomic content is 2.5 at % or less. When producing the piezoelectric thin film, scandium and aluminum are sputtered simultaneously on a substrate from a scandium aluminum alloy target material having a carbon atomic content of 5 at % or less in an atmosphere where at least nitrogen gas exists. The sputtering may be conducted also by applying an ion beam on an opposing surface of the alloy target material at an oblique angle. Moreover, aluminum and scandium may be also sputtered simultaneously on the substrate from an Sc target material and an Al target material. As a result, a piezoelectric thin film which exhibits excellent piezoelectric properties and a method for the same can be provided.

Abstract: Provided is a photochromic substance that has lower toxicity, exhibits good sensitivity in a visible light region, changes color deeply, has slow speed of color fading, has chemical and thermal stability, and has good durability. The photochromic substance has a composition represented by the formula: Ba(a-b)CabMgcSidOe:FefMgM?h where 1.8?a?2.2, 0?b?0.1, 1.4?c?3.5, 1.8?d?2.2, e=(a+c+2d), 0.0001?f, 0.0001?g, 0?h, M is at least one of Al and Eu, and M? is at least one element selected from the group consisting of Na, K, Nd, Li, S, C, Ti, V, Mn, Cr, Cu, Ni, Co, Ge, Zn, Ga, Zr, Y, Nb, In, Ag, Mo, Sn, Sb, Bi, Ta, W, La, Ce, Pr, Nd, Sm, Gd, Er, Ho, Tb, Tm, Yb, Lu, P, Cd, and Pb.

Abstract: A germanium-containing aluminum nitride piezoelectric film and a method for manufacturing an aluminum nitride piezoelectric film in which a germanium-containing aluminum nitride piezoelectric film is grown on a substrate by sputtering.

Abstract: A piezoelectric thin film composed of aluminum nitride and which contains magnesium and 31 to 120 atomic percent of niobium relative to 100 atomic percent of the magnesium, and the total content of the magnesium and the niobium relative to the total sum of contents of the magnesium, the niobium and the aluminum nitride falls within the range of 10 to 67 atomic percent.

Abstract: A piezoelectric thin film is formed through sputtering and consists essentially of scandium aluminum nitride. The carbon atomic content is 2.5 at % or less. When producing the piezoelectric thin film, scandium and aluminum are sputtered simultaneously on a substrate from a scandium aluminum alloy target material having a carbon atomic content of 5 at % or less in an atmosphere where at least nitrogen gas exists. The sputtering may be conducted also by applying an ion beam on an opposing surface of the alloy target material at an oblique angle. Moreover, aluminum and scandium may be also sputtered simultaneously on the substrate from an Sc target material and an Al target material. As a result, a piezoelectric thin film which exhibits excellent piezoelectric properties and a method for the same can be provided.

Abstract: A method for manufacturing a piezoelectric thin film including an aluminum nitride thin film containing scandium on a substrate, the method includes: sputtering step for sputtering aluminum and scandium under an atmosphere containing at least a nitrogen gas. In the sputtering step in the method according to the present invention, a scandium content rate falls within the range from 0.5% by atom to 50% by atom when a temperature of the substrate falls within the range from 5° C. to 450° C. during the sputtering step.

Abstract: A piezoelectric thin film comprising aluminum nitride containing magnesium and hafnium, wherein a content of the hafnium based on 100 atomic % of the magnesium is 8 atomic % or more and less than 100 atomic %, and a total content of the magnesium and hafnium based on a sum of a content of the magnesium, hafnium, and aluminum is in a range of 47 atomic % or less.

Abstract: A piezoelectric member that achieves a high sound speed includes a silicon-containing substrate and a piezoelectric layer. The piezoelectric layer is disposed on the silicon-containing substrate. At least a surface layer of the piezoelectric layer on a side opposite to the silicon-containing substrate is made of BxAl1-xN (0<x?0.2).

Abstract: Provided is a photochromic substance that has lower toxicity, exhibits good sensitivity in a visible light region, changes color deeply, has slow speed of color fading, has chemical and thermal stability, and has good durability. The photochromic substance has a composition represented by the formula: Ba(a-b)CabMgcSidOe:FefMgM?h where 1.8?a?2.2, 0?b?0.1, 1.4?c?3.5, 1.8?d?2.2, e=(a+c+2d), 0.0001?f, 0.0001?g, 0?h, M is at least one of Al and Eu, and M? is at least one element selected from the group consisting of Na, K, Nd, Li, S, C, Ti, V, Mn, Cr, Cu, Ni, Co, Ge, Zn, Ga, Zr, Y, Nb, In, Ag, Mo, Sn, Sb, Bi, Ta, W, La, Ce, Pr, Nd, Sm, Gd, Er, Ho, Tb, Tm, Yb, Lu, P, Cd, and Pb.