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The warpage of glass substrate in chip-on-glass (COG) assemblies were believed to be the main cause of the so-called "Mura" phenomenon in thin-film transistor liquid crystal display (TFT-LCD) panels. The main objective of the study is to characterize the process-induced deformations of an anisotropic conductive film (ACF) type of COG assembly during the ACF bonding process. For effectively modeling the process-dependent thermal-mechanical behaviors of the ACF assembly, a process-dependent simulation methodology that integrates both thermal and thermal-mechanical finite element (FE) analyses and a "death-birth" meshing scheme is proposed. In the investigation, two various types of mirobump bonding technologies, i.e., the Au alloy and composite bumps, are explored. To substantiate the validity of the proposed methodology, the modeled results are extensively compared against experimental data. Moreover, the alternative goal of the study is to provide a design guideline through the exploration of the individual or combined effect of some essential parameters on the process-induced deformations.Both the modeled and experimental results reveal that in addition to the coefficient of thermal expansion (CTE) mismatch between the die and substrate, the process-induced temperature gradient appears to be the key factor causing the deformation of the assembly, and the deformed shape of the substrate is totally opposed to that obtained from isothermal modeling. Evidence also suggests that a preheated substrate could effectively ease the maximum process-induced warpage of the substrate, while the ACF fillet would unfortunately enlarge it. Besides, it is not surprising to find that an increase of the die length would enhance the maximum process-induced warpage of the substrate, but what surprises many is that an increase of the die width would diminish it.Index Terms-Anisotropic conductive film (ACF) bonding technology, death-birth meshing scheme, finite element (FE) modeling, parametric study, process-induced warpage, response surface methods (RSMs).

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Titanium disilicide ͑TiSi 2 ͒ is a high-melting compound with excellent conductivity, which appears to have potential applications in field-emission. In the present article, TiSi 2 thin film was successfully synthesized on a silicon wafer through an in situ chloride-generated strategy by atmospheric-pressure chemical-vapor deposition. The required titanium chloride-precursor vapor was in situ produced at an elevated temperature by preloading NiCl 2 ·6H 2 O onto Ti powder with anhydrous ethanol. This synthetic strategy avoided inconvenience with the direct usage of titanium halide or titanium powder as delivering gaseous precursors. The field-emission behavior of the sample shows a turn-on field of 7.2 V / m and agrees well with the conventional Fowler-Nordheim theory. No obvious degradation was observed in a life-stability experiment period for over 100 min. The convenient and low-cost preparation of the TiSi 2 thin film and its fine field-emission performance suggest that it can serve as a good candidate for a field emitter.