Multi-layered unit including electrode and dielectric layer

摘要

A multi-layered unit according to the present invention includes a support substrate formed of platinum (Pt), a buffer layer formed on the support substrate and formed of a dielectric material containing a bismuth layer structured compound having an excellent orientation characteristic and a composition represented by Bi₄Ti₃O₁₂ and oriented in the c axis direction, and a dielectric layer formed on the buffer layer, formed of a dielectric material containing a bismuth layer structured compound having an excellent characteristic as a capacitor material and a composition represented by SrBi₄T₄O₁₅ and containing the bismuth layer structured compound 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 support substrate serving as an 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, large capacitance and an excellent dielectric characteristic.