PROBLEM TO BE SOLVED: To provide a piezoelectric thin film with excellent characteristics and a method for manufacturing the same.SOLUTION: An ultrasonic probe comprises an element chip. The element chip comprises a flexible film, a lower electrode provided on the flexible film, a piezoelectric film, and an upper electrode. The piezoelectric film has a film thickness of not less than 0.5 μm and not more than 20 μm, is composed of crystal grains having an average grain diameter of not less than 0.005 μm and not more than 0.2 μm, and does not have a layered discontinuous surface on the cross-sectional surface thereof. The piezoelectric film is also composed of a three-component system piezoelectric material represented by xPb(Mg1/3 Nb2/3)O3-yPbZrO3-zPbTiO3 (x, y, abd z represent a molar ratio, and x+y+z=1), and includes a composition in a range of the following four points of A, B, C, and D in a three-component system composition diagram of this formula:A(x=0.05,y=0.40,z=0.55)B(x=0.05,y=0.60,z=0.35)C(x=0.25,y=0.30,z=0.45)D(x=0.25,y=0.50,z=0.25)SELECTED DRAWING: Figure 14COPYRIGHT: (C)2016,JPO&INPIT【課題】良好な特性の圧電体薄膜及びその製造法を提供する。【解決手段】超音波プローブは素子チップを備え、素子チップは、可撓膜と、可撓膜上に設けられた下部電極と、圧電体膜と、上部電極と、を備え、圧電体膜は、膜厚が0.5μm以上20μm以下であり、平均粒径が0.005μm以上0.2μm以下の結晶粒からなり、かつ断面に層状の不連続面を有さず、xPb(Mg1/3Nb2/3)O3-yPbZrO3-zPbTiO3(x,y,zはモル比を表し、x+y+z=1である)で表される三成分系圧電材料からなり、かつ、この式の三成分系組成図において以下のA、B、C、及びDの四点の範囲内にある組成を有する。A(x=0.05,y=0.40,z=0.55)B(x=0.05,y=0.60,z=0.35)C(x=0.25,y=0.30,z=0.45)D(x=0.25,y=0.50,z=0.25)【選択図】図14
