Leakage current and ferroelectric memory in Nd and Sm substituted Bi4Ti3O12 films

✍ Scribed by M.S. Tomar; R.E. Melgarejo; S.P. Singh

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 384 KB
• Volume: 36
• Category: Article
• ISSN: 0026-2692
• DOI: 10.1016/j.mejo.2005.02.088

✦ Synopsis

Leakage current in ferroelectric devices is important because it affects the saturation. Rare earth substituted bismuth titanate (Bi 4 Ti 3 O 12 ) electroceramics has emerged as new material system for non-volatile ferroelectric memory. We synthesized Bi 4Kx M x Ti 3 O 12 (MZNd, Sm) for different compositions by sol-gel process and thin films were deposited by spin coating on Pt (Pt/TiO 2 /SiO 2 /Si) substrate. Room temperature leakage current and ferroelectric response was investigated on Pt/film/Pt capacitor structure. Ferroelectric response and leakage current density for different compositions are presented. Nd and Sm substituted thin films shows ferroelectric polarization (P r ) O50 and 18 mC/cm 2 , respectively, and leakage current densities about 10 K7 A/cm 2 . Large polarization in rare earth substituted Bi 4 Ti 3 O 12 layered perovskites is attributed to the dipole formation which tilts TiO 6 octahedra to Bi 2 O 2 interlayer of the unit cell.