COMPOSITION FOR FORMING BI-BASED FERROELECTRIC THIN FILM, FORMATION OF THIN FILM AND BI-BASED FERROELECTRIC THIN FILM

摘要

PROBLEM TO BE SOLVED: To obtain a Bi-based ferroelectric thin film having a great remanence value and no film fatigue without passing through a high-temperature process. SOLUTION: This composition for forming a Bi-based ferroelectric thin film is obtained by mixing metallic compounds so as to provide the metallic compositional ratio of (Sr1-m Rm ):Bi:(Ta and/or Nb)=X:Y:Z [R is one or more of La, Ce, Pr, Nd, Eu, Sm, Tb, Gd and Er; 0(m)=0.1; 0.4=X1.0; 1.5=Y=3.5 and Z=2] in an organic solvent. The resultant composition is applied onto a substrate, dried, calcined and then baked to crystallize the formed thin film. The ferroelectric film having a great remanence and slight film fatigue can be obtained by regulating the composition of the (Sr+R) to 0.4=X1.0. A part of the Sr is replaced with a rare earth element to increase the remanence.