Multi-layered unit including electrode and dielectric layer

Abstract

A multi-layered unit according to the present invention includes a support substrate formed of fused quartz, a buffer layer formed on the support substrate and formed of a dielectric material containing a bismuth layer structured compound oriented in the c axis direction, an electrode layer formed by epitaxially growing crystals of a conductive material on the buffer layer and oriented in the c axis direction, and a dielectric layer formed by epitaxially growing a dielectric material containing a bismuth layer structured compound on the electrode layer and oriented in the c axis direction. Since the thus constituted multi-layered unit includes the dielectric layer containing the bismuth layer structured compound oriented in the c axis direction, in the case of, for example, providing an upper electrode on the dielectric layer to form a thin film capacitor and applying a voltage between the electrode layer and the upper electrode, the direction of the electric field substantially coincides with the c axis of the bismuth layer structured compound contained in the dielectric layer. As a result, since the ferroelectric property of the bismuth layer structured compound contained in the dielectric layer can be suppressed and the paraelectric property thereof can be fully exhibited, it is possible to fabricate a thin film capacitor having a small size and large capacitance.

Dependencies are inferred from the claim text.