Introdução à eletromigração controlada em materiais cerâmicos: uma revisão bibliográfica

Abstract

Electromigration became established in the early days of microelectronics as a failure mechanism in metallic interconnects, but electrically driven mass transport can also be employed to enable controlled post-fabrication modification of devices. This work presents a literature review of the historical development, physical foundations, and controlled use of electromigration, with emphasis on ceramic materials, particularly complex oxides, with a primary focus on YBa2Cu3O7−δ (YBCO). It is organized into four thematic areas: classical studies of metals, mass-flux and reliability models, fabrication and control techniques, and studies of oxygen migration in functional oxides. In metals, the discussion addresses how effective force, Joule heating, microstructure, flux divergence, and mechanical stresses lead to the formation of voids and hillocks, which are classical outcomes of electromigration. In ceramics, the analysis is extended through electrochemical potential and defect chemistry, since the displacement of ions and vacancies alters stoichiometry, oxidation states, and electronic properties. YBCO is adopted as the central case because oxygen occupancy and ordering in the CuO chains regulate hole doping in the CuO2 planes, allowing its resistance and superconducting critical temperature to be modified. The fabrication of constrictions and nanogaps, resistance- or conductance-based feedback, electropulsing, and polarity reversal are also examined as strategies for controlling electromigration. Taken together, the literature review and analyses conducted show that the same mass transport process that limits interconnect reliability can, when controlled, be employed as a nanofabrication technique for defect nanoengineering and the localized tuning of material and device properties.