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A new 2D titanium carbide (Ti3C2), a low dimensional material of the MXene family has attracted remarkable interest in several electronic applications, but its unique structure and novel properties are still less explored in piezoelectric energy harvesters. Herein, a systematic study has been conducted to examine the role of Ti3C2 multilayers when it is incorporated in the piezoelectric polymer host. The 0.03 g/L of Ti3C2 has been identified as the most appropriate concentration to ensure the optimum performance of the fabricated device with a generated output voltage of about 6.0 V. The probable reasons might be due to the uniformity of nanofiller distribution in the polyvinylidene difluoride (PVDF) and the incorporation of Ti3C2 in a polymer matrix is found to enhance the β-phase of PVDF and diminish the undesired α-phase configuration. Low tapping frequency and force were demonstrated to scavenge electrical energy from abundant mechanical energy resources particularly human motion and environmental stimuli. The fabricated device attained a power density of 14 µW.cm−2 at 10.8 MΩ of load resistor which is considerably high among 2D material-based piezoelectric nanogenerators. The device has also shown stable electrical performance for up to 4 weeks and is practically able to store energy in a capacitor and light up a LED. Hence, the Ti3C2-based piezoelectric nanogenerator suggests the potential to realize the energy harvesting application for low-power electronic devices. [ABSTRACT FROM AUTHOR]

We compare solvent treatments using fluorinated alcohol (2,2,3,3,4,4,5,5-octafluoro- 1-pentanol) and ethanol in improving the efficiency of a polymer organic light-emitting diode (OLED) by spin coating the solvent on top of the emissive layer. The presence of fluorinated alcohol is confirmed using x-ray photoelectron spectroscopy. The electron current is found to be significantly enhanced following solvent treatment while the hole current remains the same. The solvent treatment by fluorinated alcohol on top of a ‘super-yellow’ poly-(p-phenylenevinylene) (SY-PPV) based OLED results in efficiency as high as 19.2 lm W−1 (20.9 cd A−1) at a brightness of 1000 cd m−2. The improvement of device efficiency through the use of fluorinated alcohol treatment can be attributed to its large dipole, which lowers the electron injection barrier. This work also suggests that fluorinated alcohol might be a better trap passivator for electrons than ethanol. [ABSTRACT FROM AUTHOR]

Purpose – This paper aims to discuss the effects of ionic contaminations on the die surface of high lead flip chip ball grid array (FCBGA) package. Ionic contaminations from the flux residue, formed during the die attachment process, could affect the package long-term performance. Design/methodology/approach – Thus, the flux-cleaning process was implemented and the cleanliness effect was evaluated. Cleaning experiments using a new water-based solvent were carried out to investigate the flux-cleaning efficiency. The test packages were then evaluated via ion chromatography (IC). Findings – Ion chromatograms show that there are high levels of ionic elements detected prior to the cleaning process. After the cleaning process, the contamination levels reduced significantly. Originality/value – The value of the work here is testing of the new environmental friendly water-based MPC® cleaning efficiency. The reduction of ionic contamination is thus reported. [ABSTRACT FROM AUTHOR]

Purpose – The increased use recently of area-array technology in electronic packaging has similarly increased the importance of predicting the thermal distribution of area-array solder interconnection. As the interconnection technology for flip chip package is getting finer and smaller, it is extremely difficult to obtain the accurate values of thermal stresses by direct experimental measurements. Different types of solder bumps used for interconnection would also influence the thermal distribution within the package. Because the solder balls are too small for direct measurement of their stresses, finite element method (FEM) was used for obtaining the stresses instead. Design/methodology/approach – This paper will discuss the results of the thermal stress distribution using numerical method via ABAQUS software. The variation of the thermal stress distribution with the temperature gradient model was evaluated to study the effects of the different material thermal conductivity of solder bumps used. A detailed 2D finite element model was constructed to perform 2D plain strain elastoplastic analysis to predict areas of high stress. Findings – It is found that thermal distribution of solder bumps starts to propagate from the top region to the bottom region of the solder balls. Other than that, thermal stress effect increases in parallel with the increasing of the temperature. The simulation results shows that leaded solder balls, SnPb have higher maximum thermal stress level compared to lead-free SAC solder balls. Originality/value – The paper describes combination of stress with thermal loading correlation on a flip chip model. The work also shows how the different thermal conductivity on solder balls influences the thermal induced stress on the flip chip package. [ABSTRACT FROM AUTHOR]

Over the past 20 years, rapid technological advancement in the field of microfluidics has produced a wide array of microfluidic point-of-care (POC) diagnostic devices for the healthcare industry. However, potential microfluidic applications in the field of nutrition, specifically to diagnose iron deficiency anemia (IDA) detection, remain scarce. Iron deficiency anemia is the most common form of anemia, which affects billions of people globally, especially the elderly, women, and children. This review comprehensively analyzes the current diagnosis technologies that address anemia-related IDA-POC microfluidic devices in the future. This review briefly highlights various microfluidics devices that have the potential to detect IDA and discusses some commercially available devices for blood plasma separation mechanisms. Reagent deposition and integration into microfluidic devices are also explored. Finally, we discuss the challenges of insights into potential portable microfluidic systems, especially for remote IDA detection. [ABSTRACT FROM AUTHOR]