Propriedades magnéticas e magnetorresistência em filmes finos de Ni81Fe19

• Ano de defesa: 2013
• Autor(a) principal: Nascimento Júnior, Cristovão Porciano do
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Física; Física da Matéria Condensada; Astrofísica e Cosmologia; Física da Ionosfera
• Palavras-chave em Português: Filmes finos. Permalloy. Materiais ferromagnéticos. Magnetorresistência anisotrópica; Thin films. Permalloy. Ferromagnetic materials. Hysteresis. Anisotropic magnetoresistance; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
• Link de acesso: https://repositorio.ufrn.br/jspui/handle/123456789/18605

The ferromagnetic materials play an important role in the development of various electronic devices and, have great importance insofar as they may determine the efficiency, cost and, size of the devices. For this reason, many scientific researches is currently focused on the study of materials at ever smaller scales, in order to understand and better control the properties of nanoscale systems, i.e. with dimensions of the order of nanometers, such as thin film ferromagnetic. In this work, we analyze the structural and magnetic properties and magnetoresistance effect in Permalloy-ferromagnetic thin films produced by magnetron sputtering. In this case, since the magnetoresistance effect dependent interfaces of thin films, this work is devoted to the study of the magnetoresistance in samples of Permalloy in nominal settings of: Ta[4nm]/Py[16nm]/Ta[4nm], Ta[4nm]/Py[16nm]/O2/Ta[4nm], Ta[4nm]/O2/Py[16nm]/Ta[4nm], Ta[4nm]/O2/Py[16n m]/O2/Ta[4nm], as made and subjected to heat treatment at temperatures of 160ºC, 360ºC e 460ºC, in order to verify the influence of the insertion of the oxygen in the layer structure of samples and thermal treatments carried out after production of the samples. Results are interpreted in terms of the structure of the samples, residual stresses stored during deposition, stresses induced by heat treatments and magnetic anisotropies