PIEZOELECTRIC THIN FILM ELEMENT, AND PIEZOELECTRIC THIN FILM DEVICE

摘要

Disclosed are a piezoelectric thin film element and a piezoelectric thin film device which have improved piezoelectric properties and high performance and can be produced in improved yields. The piezoelectric thin film element (1) comprises: a substrate (10); and a piezoelectric thin film (40) which is arranged on the substrate (10), has at least one crystal structure represented by general formula (NaxKyLiz)NbO3 (0=x=1, 0=y=1, 0=z=0.2, x+y+z=1) and selected from the group consisting of a pseudo-cubic crystal, a hexagonal crystal and an orthorhombic crystal, and contains an inert gas element at a ratio of 80 ppm or less by mass.