Development of heterostructured thin films towards artificial multiferroics

• Grant number: 14/18247-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2014
• Effective date (End): September 30, 2015
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Alexandre Zirpoli Simões
• Grantee: Pedro Paulo da Silva Ortega
• Host Institution: Faculdade de Engenharia (FEG). Universidade Estadual Paulista (UNESP). Campus de Guaratinguetá. Guaratinguetá , SP, Brazil
• Associated research grant: 13/07296-2 - CDMF - Center for the Development of Functional Materials, AP.CEPID

Abstract

The aim of this proposal is to contribute to the research that has been developed in the Department of Materials and Technology (DMT) of the Guaratinguetá Engineering Faculty. In this research, it was proposed the development of thin films with special magnetoelectric features funded by FAPESP in regular project 2013 /08141-2. With the rapid growth of portable electronic devices market, a demand for compact sources, lightweight power and, above all, low cost is required. Most of these integrated circuits using ferroelectric random access memories (FeRAMs). However, these memories are resistant to application due to phenomena of fatigue, retention and "imprint", decreasing the efficiency of the capacitor. Aiming to overcome these obstacles, the synthesis of multiferroic films has been investigated due to the phenomenon of magnetoelectric coupling. For the application of multiferroic materials in multiple states memories is to develop heterostructured thin films. Two multiferroic materials can be employed: the bismuth ferrite (BiFeO3) and lanthanum ferrite (LaFeO3). The idea is that during the coupling between different interfaces, new possibilities of storing data in memory elements may be created non-destructively. Our motivation is focused on the similar magnetic properties of these materials, allowing the introduction of stresses at the interfaces, generating the magnetoelectric coupling and improving their properties. This type of interaction will enhance the applicability of multi-state memory, in which information can be stored in the polarization and spontaneous magnetization states, improving the market with the increase in operation speed and storage capacity of information. This project proposes to study the magnetoelectric coupling in heterostrctured thin films of BiFeO3 and LaFeO3 from the polymeric precursor and deposited by the "spin-coating" method. The influence of the thickness and the effect of stress on the interface will be studied in order to improve the quality of such films for application in multiple states memories.