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We proposed a single-molecule magnetic junction (SMMJ), composed of a dissociated amine-ended benzene sandwiched between two Co tip-like nanowires. To better simulate the break junction technique for real SMMJs, the first-principles calculation associated with the hard-hard coupling between a amine-linker and Co tip-atom is carried out for SMMJs with mechanical strain and under an external bias. We predict an anomalous magnetoresistance (MR) effect, including strain-induced sign reversal and bias-induced enhancement of the MR value, which is in sharp contrast to the normal MR effect in conventional magnetic tunnel junctions. The underlying mechanism is the interplay between four spin-polarized currents in parallel and anti-parallel magnetic configurations, originated from the pronounced spin-up transmission feature in the parallel case and spiky transmission peaks in other three spin-polarized channels. These intriguing findings may open a new arena in which magnetotransport and hard-hard coupling are closely coupled in SMMJs and can be dually controlled either via mechanical strain or by an external bias. [ABSTRACT FROM AUTHOR]

Development of flip-chip-on-glass (FCOG) assembly technology using anisotropic conductive adhesive/film (ACA/ACF) is currently underway to achieve fine pitch interconnections between driver IC and fiat panel display. Conductive adhesives are characterized by fine-pitch capability and more environment compatibility. Anisotropic conductive adhesive/film (ACA/ACF) is composed of an adhesive resin and conductive particles, such as metallic or metal-coated polymer particles. In contrast to a solder type flip chip interconnection, the electric current passing through conductive particles becomes the dominant conduction paths. The interconnection between the particles and the conductive surfaces is constructed by the elastic/plastic deformation of conductive particles with contact pressure, which is maintained by tensile stress in the adhesive. Although loss of electric contact can occur when the adhesive expands or swells in the Z-axis direction, delamination and cracking can occur in the adhesive layer while the tensile stress is excessive. In addition to performing processing simulations as well as reliability modeling, this research investigates the contact force that is developed and relaxed within the interconnection during the process sequence by using nonlinear finite element simulations. Environmental effects, such as high temperature and thermal loading, are also discussed. Moreover, a parametric study is performed for process design. To improve performance and reliability, variables such as ACF materials, proper processing conditions are discussed as well. Furthermore, this study presents a novel method called equivalent spring method, capable of significantly reducing the analysis CPU time and make process modeling and contact analysis of the 3D ACA/ACF process possible.