Abstract: A ferroelectric thin film coated substrate is obtained by a producing method of forming a metal oxide buffer layer on a substrate, forming a first crystalline ferroelectric thin film thereon by means of a MOCVD method and forming a second ferroelectric thin film with a film thickness thicker than that of the first ferroelectric thin film thereon by means of the MOCVD method at a temperature lower than that of the first ferroelectric thin film. This producing method makes it possible to produce a ferroelectric thin film, where its surface is dense and even, a leakage current properties are excellent and sufficiently large remanent spontaneous polarization is shown, at a lower temperature.

Abstract: A ferroelectric thin film coated substrate is obtained by a producing method of forming a crystalline thin film on a substrate by means of a MOCVD method at a substrate temperature at which crystal grows and of forming a ferroelectric thin film on the crystalline thin film by means of the MOCVD method at a film forming temperature, which is lower than the film forming temperature of the crystalline thin film. This producing method makes it possible to produce a ferroelectric thin film, where a surface of the thin film is dense and even, leakage current properties are excellent and sufficiently large remanent spontaneous polarization is shown, at a lower temperature.

Abstract: A ferroelectrics thin-film coated substrate is manufactured in a low-temperature process by using a ferroelectrics having a dense and even surface and exhibiting a large residual spontaneous polarization. A ferroelectrics thin-film coated substrate has a structure with a buffer layer, a growth layer allowing a ferroelectrics thin-film to grow, and a ferroelectrics thin-film made of a ferroelectric material having a layered crystalline structure expressed in the chemical formula Bi.sub.2 A.sub.m-1 B.sub.m O.sub.3m+3 (A is selected from Na.sup.1+, K.sup.1+, Pb.sup.2+, Ca.sup.2+, Sr.sup.2+, Ba.sup.2+, Bi.sup.3+ and the like, B is selected from Fe.sup.3+, Ti.sup.4+, Nb.sup.5+, Ta.sup.5+, W.sup.6+ and Mo.sup.6+, and m is an integer not less than 1) formed in succession.

Abstract: A close a-axis orientating film having a smooth surface and excellent ferroelectric characteristics is manufactured at a low temperature with preferable reproducibility to apply ferroelectric Bi.sub.4 Ti.sub.3 O.sub.12 to development of various kinds of devices such as a ferroelectric non-volatile memory, a pyroelectric sensor, etc. A ferroelectric Bi.sub.4 Ti.sub.3 O.sub.12 thin film is formed on a substrate through a titanium oxide buffer layer so that closeness and surface smoothness of the Bi.sub.4 Ti.sub.3 O.sub.12 thin film manufactured on the titanium oxide buffer layer can be improved.

Abstract: A ferroelectric thin film coated substrate is obtained by a producing method of forming a crystalline thin film on a substrate by means of a MOCVD method at a substrate temperature at which crystal grows and of forming a ferroelectric thin film on the crystalline thin film by means of the MOCVD method at a film forming temperature, which is lower than the film forming temperature of the crystalline thin film. This producing method makes it possible to produce a ferroelectric thin film, where a surface of the thin film is dense and even, leakage current properties are excellent and sufficiently large remanent spontaneous polarization is shown, at a lower temperature.

Abstract: The present invention provides a substrate providing a ferroelectric crystal thin film which includes an electrode formed on a semiconductor single crystal substrate and a ferroelectric crystal thin film of Bi.sub.4 Ti.sub.3 O.sub.12 formed on the electrode through the intermediary of a buffer layer.