Abstract: This ScAlN laminate includes a substrate, an intermediate layer formed on the substrate and a ScAlN thin film formed on the intermediate layer, and a nearest neighbor distance, which is a distance between atoms closest to each other in a lattice plane parallel to a surface of the intermediate layer, is shorter than the a-axis length of the ScAlN thin film.

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: 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: 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.