Pbnzt ferroelectric film, sol-gel solution, film forming method and method for producing ferroelectric film

Abstract

To provide a PBNZT ferroelectric film capable of preventing sufficiently oxygen ion deficiency. The PBNZT ferroelectric film according to an embodiment of the present invention is a ferroelectric film including a perovskite-structured ferroelectric substance represented by ABO3, wherein the perovskite-structured ferroelectric substance is a PZT-based ferroelectric substance containing Pb2+ as A-site ions and containing Zr4+ and Ti4+ as B-site ions, and the A-site contains Bi3+ as A-site compensation ions and the B-site contains Nb5+ as B-site compensation ions.

1 . A method for producing a ferroelectric film comprising the steps of:
 preparing a sol-gel solution including a raw material solution including: a hydrolysis condensation polymerization of an alkoxide raw material including Pb, Bi, Nb, Zr and Ti and heteropolyacid; and polar solvents and unsaturated fatty acids;   coating said sol-gel solution on a substrate to form a coated film on said substrate;   subjecting said coated film to temporary burning at a temperature of 25 to 450° C. to form a ferroelectric material film on said substrate; and   heat-treating said ferroelectric material film at a temperature of 450 to 800° C. to produce a ferroelectric film including a perovskite-structured ferroelectric substance obtained by crystallizing said ferroelectric material film.   
     
     
         2 . The method for producing a ferroelectric film according to  claim 1 , wherein said ferroelectric film is a PBNZT ferroelectric film comprising a perovskite-structured ferroelectric substance represented by (Pb 1-X Bi X )((TiZr) 1-Y Nb Y )O 3 , wherein:
 X is 0.05 to 0.1; and   Y is 0.05 to 0.1.   
     
     
         3 . The method for producing a ferroelectric film according to  claim 1 , wherein said ferroelectric film has a relative permittivity of 400 or more. 
     
     
         4 . A ferroelectric film being formed by the method for producing a ferroelectric film according to  claim 3  and having a relative permittivity of 400 or more.