Patent ID: 9586401
Date: 2017-03-07
CPC Classifications: B41J,H01L,Y10T

Claim:
1. A piezoelectric thin film element, comprising: a substrate; a vibration plate provided on the substrate; a lower electrode provided on the vibration plate, the lower electrode including at least a platinum metal film or an iridium metal film; a piezoelectric film provided on the lower electrode, the piezoelectric film including a polycrystalline body; and an upper electrode provided on the piezoelectric film, the lower electrode being provided on an upper portion of a titanium oxide film formed on the vibration plate, the lower electrode including a platinum metal film or an iridium metal film formed on the titanium oxide film, and the platinum metal film or the iridium metal film being a precise film without having a hole that is in a crystal grain boundary of the platinum metal film or a crystal grain boundary of the iridium metal film and that permits Pb diffusion of Pb in the piezoelectric film into the platinum metal film or the iridium metal film, the precise film having a thickness of 150 nm or more and 250 nm or less and having an average particle diameter of crystal of 250 nm or more.