Lower electrode for piezoelectric element, and piezoelectric element provided with lower electrode

摘要

In the present invention, a half-value width of a rocking curve, an average roughness of a surface, and an average grain diameter are all specified at one time with respect to a Pt layer that constitutes a lower electrode for a piezoelectric element, thereby stably film-forming the Pt layer having excellent characteristics, and stably forming, on the Pt layer, a piezoelectric thin film having excellent characteristics.

主权项

1. A lower electrode for a piezoelectric element, which acts as a lower electrode underlying a piezoelectric thin film formed over a substrate, comprising:
a Pt layer, wherein with respect to the Pt layer, a full width at half maximum of a rocking curve in X-ray diffraction of a (111) plane of Pt is not more than 2.2°, a surface roughness thereof satisfies at least one of following: a root-mean-square roughness RMS of not more than 1.0 nm, and an arithmetic mean roughness Ra of not more than 0.8 nm, and an average grain size of Pt is not less than 200 nm.