Plastic Ball Grid Array Encapsulation Process Simulation on Rheology Effect

The integrated circuit should be encapsulated for protection from their intended environment. This paper presents the flow visualization of the plastic ball grid array (PBGA) chip encapsulation process considering of the rheology effect. In the molding process, encapsulant flow behavior is modeled by Castro-Macosko viscosity model with considering curing effect and volume of fluid technique is applied for melt front tracking. The viscosity model is written into C language and compiled using User-Defined Functions into the FLUENT analysis. Three types of Epoxy Molding Compound namely case 1, 2, and 3 were utilized for the study of fluid flow inside the mold cavity. The melt front profiles and viscosity versus shear rate for all cases are analyzed and presented. The numerical results are compared with the previous experimental results and found in good conformity. In the present study, case 1 with greater viscosity shows the higher air trap and higher pressure distributions.

Customer’s acceptance, usage and M-satisfaction of Mobile Hotel Reservation Apps (MHRA) / Mohd Noor Ismawi Ismail...[et al.]

This conceptual paper aims to explore the relationship between customer acceptance and the usage of Mobile Hotel Reservation Apps (MHRA) on Mobile satisfaction (M-satisfaction). The MHRA booking is the latest booking channel offered by the hoteliers in favor of mobility and service failures exposed by the traditional method of room booking. Nonetheless, the actual usage and the success of this app have not been explored yet. The Unified Theory of Acceptance and Use of Technology (UTAUT2) was adopted as the underpinning theory of this study. The UTAUT2 framework was modified by incorporating Msatisfaction as the dependent variable. Seven propositions were suggested based on the literature review

Reliability Assessment Of Self-Alignment Assemblies Of Chip Component After Reflow Soldering Process

Reliability of surface mount components and interconnect are significant issues in electronic manufacturing. Although the reliability of devices has been broadly studied,here we are focusing on the reliability of the solder joint after the self-alignment phenomena during reflow soldering.In this study,the quality of the self-alignment assemblies was analyzed relate to the joint shear strength according to the JIS Z3 198-7 standard and the inspection according to IPC-A-610E standard.The results from reliability study indicate that the shear strength of the misalignment component of solder joints indeed depends on the degree of chip component misalignment.For shift mode configuration in the range of 0-300µm,the resulted chip assembly inspection after the reflow process was in line with the IPC-A-610E standard

Effect of ceramic coating in combustion and cogeneration performance of Al2O3 porous medium

In this work, the effect of SiC-, Ni-, and Cr-based coating on the performance of porous medium burner are evaluated. A dip-coating technique was used to coat SiC, Ni, and Cr powders on a pre-sintered porous Al2O3 substrate. The morphological properties of the sintered Al2O3 plain substrates and coating layer were observed using a light microscope and scanning electron microscopy. The combustion analyzer has been calibrated and used to measure the emissions during the experiment. Thermoelectric cells were used in the cogeneration system to generate electricity from the porous medium burner. The results show a significant improvement in the maximum surface flame temperature and combustion emissions over the plain substrate. The highest recorded surface flame temperature at flow rate of 0.25 L/min was 750°C for SiC-coated, 741°C for Cr-coated, 739°C for Ni-coated and plain substrate registered a temperature of only 634 °C. An 18% increase in flame temperature was recorded for SiC-coated substrate when compared to the plain substrate. Moreover, the coated substrate reduced the emissions CO, COu and NOx. It was also found that; SiC-coated substrate reported the best overall power output when compared to the plain substrate

Risk Assessment of Wave Energy Converter At Kuantan Port, Pahang

Harvesting energy from ocean waves remains an untapped resource, and it is considered a new methodology in renewable energy, especially in Malaysia. This research is based on a project at Kuantan Port that used Wave Energy Converter (WEC) as a platform to generate energy from waves and convert it into electricity. The purpose of this research is to conduct a risk assessment before the execution of the project by referring to the International Organization for Standardization (ISO) 31000 and Risk Management Guidelines: Companion to AS/NZS 4360:2004. It started from risk identification and planned a mitigation way to reduce the grade of risk. These mitigations will be monitored throughout the project to avoid any accidents or harm during construction and installation in the future. The assessment will be using a qualitative analysis method that will gather all the possible risks that impact the project and propose the actions to mitigate the risk. The assessment will also consider the likelihood, seriousness, and weightage to determine the risk level. The risk assessment is divided into six clusters: project management, hydrography, mechanical, electrical, civil, and safety and security. After analysis, each cluster has given their feedback on the risk assessment and their cluster-s risk grade. This research has found that the risk grade is at grade C, which needs the risk assessment of this project to reduce the likelihood, seriousness, and required mitigation actions. Eventually, after the mitigation plan is applied to each risk, the grade of risk is reduced to N

Characteristic airflow patterns during inspiration and expiration: experimental and numerical investigation

A simplified experimental nasal model was designed and an experimental setup was developed to facilitate both inspiratory and expiratory flow measurements. Particle image velocimetry (PIV) and resistance measurements were conducted. The purpose of this work was primarily to demonstrate a simple way of carrying out experiments for a replica human nose in order to validate numerical studies. The characteristic recirculatory patterns observed explicitly as a consequence of inspiration and expiration were investigated. The resistance study showed similar patterns of resistance for both experimental and numerical results for various flow rates. The PIV results showed that inspiratory and expiratory flows had characteristic flow patterns that can be distinguished based on their recirculatory flow patterns

Pengawalan pertumbuhan sebatian antara logam sambungan pateri-papan litar bercetak menggunakan salutan nikel

Bahan aloi pateri dalam kumpulan Sn-Ag-Cu (SAC) merupakan bahan pematerian yang bebas plumbum digunakan secara meluas dalam industri elektronik. Antarasambungan pateri bertindak untuk menghubungkan komponen elektronik pada papan litar bercetak (PCB). PCB memainkan peranan yang penting dalam tindak balas pematerian dan mikrostruktur antarasambungan pateri-substrat seterusnya mempengaruhi kebolehharapan suatu sambungan pateri. Pes pateri Sn0.3Ag0.7Cu (SAC0307) dipaterikan pada tiga jenis PCB iaitu PCB tanpa salutan (PCB/Cu) sebagai sampel kawalan, PCB dengan salutan timah (PCB/Sn) dan PCB dengan salutan nikel (PCB/Ni). Kajian ini bertujuan untuk mengkaji kesan salutan permukaan PCB ke atas pertumbuhan sebatian antara logam (IMC) selepas uji kaji penuaan sesuhu yang berbeza selama 1000 jam. Keputusan menunjukkan purata ketebalan lapisan IMC ~ 5.7 μm serta kadar pertumbuhan lapisan IMC yang paling rendah adalah selari dengan tenaga pengaktifan tertinggi dengan salutan Ni iaitu 41 kJ/mol berbanding PCB/Cu dan PCB/Sn. Ini bermakna salutan Ni pada PCB mampu mengawal pertumbuhan IMC sehingga lebih kurang 40% berbanding salutan Sn dan tanpa salutan

Soldering Characteristics And Thermomechanical Properties Of Pb-Free Solder Paste For Reflow Soldering

A deep understanding in thermal characteristics of lead-free solder paste grades is one of the most crucial factors when dealing with reflow soldering process. These temperatures are critical parameters for proper settings of the real reflow process. This report is devoted to discussing the findings obtained during utilization of differential scanning calorimetry (DSC) and calculation using MATLAB to identify the latent heat, solidus and liquidus temperature, and surface tension applicable to numerically simulate the real process of reflow soldering. It can be stated that the equilibrium solidus and liquidus temperatures during solidification process are not a reversal of the melting process, with the solid phase equilibrium occurred at a lower temperature due to the difficulty of ß-Sn nucleation. Amount of heat energy released during solidification differs less than 10% for SAC405 and less than 1% for SAC105 with the latent heat of fusion during the melting process