Yen-Chun Liu

Failure Analysis of Anisotropic Conductive Film Packages With Misalignment Offsets

This paper utilizes the V-shaped curve method to analyze the failure probability of anisotropic conductive film (ACF) packages with various degrees of IC/substrate misalignment. In evaluating the failure probability of the ACF package, the probability of an opening failure in the vertical gap between the pads is determined in accordance with a Poisson function, while the probability of a bridging failure between the pads in the pitch direction is computed using a bridging model. In computing the opening and bridging probabilities, the Poisson function and bridging model are modified to take account of the effects of package misalignments on the effective conductive area between opposing pads and the bridging-path length between neighboring pairs of opposing pads, respectively. The opening and bridging probabilities are then combined using probability theory to establish an overall failure prediction model for the IC/substrate assembly. It is shown that, for any given value of the IC/substrate misalignment, the modified V-shaped curve method enables not only the failure probability of the ACF package to be reliably predicted but also an estimate to be made of the optimal ACF volume fraction. The results show that the semilogarithmic failure probability increases approximately linearly with the volume fraction for both uni- and bidirectional misalignments of the ACF package. The optimal volume fractions for ACF packages with misalignments not considered in this paper can be derived from the current results via a process of interpolation.

Effects of Fly Ash/Slag Ratio and Liquid/Binder Ratio on Strength of Alkali-Activated Fly Ash/Slag Mortars

The purpose of this study is to investigate the effects of fly ash/slag ratio and liquid/binder ratio on strength of alkali-activated fly ash/slag (AAFS) mortars. Three liquid/binder ratios of 0.35, 0.5 and 0.65 and three fly ash/slag ratios of 100/0, 50/50, and 0/100 were selected as variables to design and produce mixes of AAFS mortars. The compressive strength and flexural strength of alkali-activated fly ash/slag mortars were discussed and compared with reference mortars produced using ordinary Portland cement (OPC) mortars. Based on the results, both fly ash/slag ratio and the liquid/binder ratio are significant factors influencing the strengths of AAFS mortars. The strength of AAFS mortars except alkali-activated fly ash mortars is higher than that of OPC mortars. When the fly ash/slag ratio reaches 50/50, the AAFS mortars possesses the highest strength compared with the other mortars.

Failure Probability Estimation of Anisotropic Conductive Film Packages With Asymmetric Upper-to-Lower Pad Size and Misalignment Offsets

Anisotropic conductive films (ACFs) are widely used in the packaging of flat panel displays and liquid crystal displays and for attaching bare chips to both flexible and rigid substrates. This paper utilizes the V-shaped curve method to analyze the failure probability of ACF packages with an asymmetric upper/lower pad size and misalignment offsets. In the proposed method, the probability of opening failures is modeled using a Poisson function, modified to take into account the effects of the pad-width difference and misalignment offset on the effective conductive area between opposing pads. Meanwhile, the probability of bridging failures is evaluated using an enhanced bridging model based on the distance between the neighboring pad pairs in the array. The failure probability of the pad array is evaluated as a function of both the difference in width of the upper and lower pads and the degree of misalignment between the opposing pads in the array. The results show that the V-shaped curve method provides the means to predict the ACF volume fraction which minimizes the failure probability of the ACF assembly given a knowledge of the pad-width difference and the misalignment offset. In addition, it is shown that when the misalignment offset is greater than the pad-width difference, the minimum failure probability reduces as the pad-width difference increases due to the corresponding increase in the effective conductive area between opposing pads. Conversely, when the misalignment offset is less than the pad-width difference, the minimum failure probability increases with an increasing pad-width difference due to the corresponding reduction in the effective conductive area between the pads.

Optimal Charge and Discharge Capacity Effects of the Sintering Process on LiMn2O4 by the Solid-State Reaction Method

This study investigates the optimal charge and discharge capacity of the sintering process on the lithium battery spinel - LiMn2O4. Both Li2CO3 and Mn3O4 are utilized to synthesize the cathode material LiMn2O4 using the solid-state reaction. Cathode materials are processed to fabricate batteries at temperatures ranging from 800°C to 900°C. Test results reveal that the highest initial discharge capacity of 105.19 mAhg-1 (theoretically at 148 mAhg-1) has been obtained at the temperature of 850°C in the sintering process for synthesis of LiMn2O4. In addition, the initial discharge capacity can be increased to 140.51 mAhg-1 with both overdosing the amount of lithium by 2% and increasing the range of operating voltage. The increasing of the charge voltage ranges from 4.5V to 4.8V and reducing of the discharge voltage ranges from 3.0V to 2.8V.

Effect of the Doping Ni and Overdosing Lithium for Synthesis LiMn2O4 Cathode Material by the Solid State Reaction Method

The study with Li2CO3 and Mn3O4 through the solid state reaction makes cathode material for lithium battery spinel - LiMn2O4. According to past literature, under the solid-state reaction. The experiment carries out sintering at temperature of 850°C.. Cathode materials under these sintering temperatures are made to fabricate battery. For Ni doped LiMn2O4, the capacitance decreasing speed is slow and stable; after 15 times charging-discharging cycles, the attrition rates were 3.05 % or less. The result of experiment demonstrates that the best sintering temperature is at 850°C. Under the condition of 850°C, various contents for extra amount of lithium (1.02 mole-1.1 mole) are fabricated and range of working voltage is released. It is found a further increase of initial capacity to 140.51 mAh/g. LiMn2O4 further extends circulation and usage.

The use of waste SNCR catalysts to produce a nano-TiO2 photo-catalyst and to degrade wastewater from the dye making industry

This study recycles titanium dioxide (TiO2) that is contained in waste selective non-catalytic reduction (SNCR) catalysts using acid or alkali. The waste SNCR is then filtered, baked, ground and calcined to form a photo-catalytic powder. The nano-TiO2 photo-catalysts that are obtained using both processes are then tested and compared. The two TiO2 photo-catalysts that are produced from waste SNCR catalysts have a diameter of 30-40 nm. Energy dispersive spectrometry (EDS) and inductively coupled plasma (ICP) are used to determine the elemental composition of TiO2 and X-ray diffraction (XRD) is used to determine the crystalline phase. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to determine the surface morphology, the structure and the particle size. The effect of placing porous TiO2 in a suspension is also determined. This study demonstrates the production of a photo-catalyst from an SNCR catalyst and its effect in advanced oxidation processes (AOP). When everdirect supra turquoise blue (FBL) dye wastewater is degraded in the presence of ultraviolet (UV) /TiO2, more than 90% of the total oxidizable carbon (TOC) is removed.

The Study of Phenol Wastewater Treatment by Series-Membrane Bioreactor Combine Bio-Reagent

This present research mainly use bio-reagent process to degradation of medium to high strength phenol. To developing high efficiency process, the hollow fiber series-member bioreactor by Bacillus suctilis to treatment of phenol wastewater. The dependence of phenol degradation rate on biomass was studied, in which reciprocal hollow fiber series-member bioreactor. The result indicate the Bacillus suctilis biomass can efficiency of phenol degradation the initial concentration from 500 mg/L to 0 mg/L in bio reactor 75 hrs, and degradation rate is 6.67 mg phenol/L hr.