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Abstract: Air-oxidation behavior of a Zr50Cu43Al7 bulk metallic glass (ZCA7-BMG) was studied over the temperature range of 400–500°C. The oxidation kinetics of the ZCA7-BMG generally followed a multiple-stage parabolic-rate law with its steady-state parabolic-rate constants (k p values) decreasing with increasing temperature, indicative of the occurrence of kinetics inversion. The scales formed on the ZCA7-BMG were strongly dependent on temperature, consisting mostly of tetragonal ZrO2 and CuO, and minor amounts of monoclinic ZrO2 and Cu2O at 400°C, while Cu2O was completely absent at T ⩾450°C. In addition, a minor amount of Al2O3 was further observed after the oxidation at 500°C, whose formation is responsible for the lowest oxidation rate, as compared to those at T ⩽450°C. [Copyright &y& Elsevier]

Process capability indices CPU and CPL have been widely used in the microelectronics manufacturing industry as capability measures for processes with one-sided specification limits. In this paper, the theory of statistical hypothesis testing is implemented for normal processes, using the uniformly minimum variance unbiased estimators of CPU and CPL. Efficient SAS computer programs are provided to calculate the critical values and the p-values required for making decisions. Useful critical values for some commonly used capability requirements are tabulated. Based on the test a simple but practical step-by-step procedure is developed for in-plant applications. An example on the voltage level translator manufacturing process is given to illustrate how the proposed procedure may be applied to test whether the process meets the preset capability requirement. [Copyright &y& Elsevier]

Abstract: The effect of Si addition on the oxidation of (Cu43Zr43Al7Ag7)99.5Si0.5 bulk metallic glass (CZ43S-BMG) was investigated over the temperature range of 375–500°C in dry air. The results generally showed that the oxidation rates of the CZ43S-BMG followed a multi-stage parabolic-rate law, and the oxidation rate constants (k p values) fluctuated with increasing temperature. It was found that the k p values of the CZ43S-BMG were slightly slower than those of the Si-free glassy alloy (Cu43Zr43Al7Ag7, named as CZ43-BMG). The scales formed on the CZ43S-BMG strongly depend on temperature, consisting of 3 different modifications of ZrO2 and CuO, and minor amounts of Cu2O (formed at T ≥425°C) and Al2O3 (only detected at 500°C). In addition, the glassy substrate remained amorphous nature at T ≤400°C, while it transferred to the crystalline phases of Cu10Zr7, ZrAl, and ZrSi2 after the oxidation at higher temperatures. [ABSTRACT FROM AUTHOR]

This paper aims to measure and simulate the warpages of 3D through-silicon via (TSV) die-stacked dynamic-random-access-memory (DRAM) packages during the manufacturing process. The related die stresses and keep-out zone (KOZ) for the stacked dies in the packages at room temperature are further calculated with the validated simulation model. The out-of-plane deformations (or warpages) of the packages from the full-field shadow moiré are documented under temperature loading and found consistent with those from finite-element method (FEM). The results of the stresses and KOZs at the proximity of a single TSV for each die in the package at room temperature are presented. It is found that the sizes of KOZs in four-die stacked DRAM packages with and without epoxy molding compound (EMC) at room temperature are dominated by the horizontal pMOS transistors and more than double the size in wafer-level die. The sizes of KOZs at each die are similar in this four-die stacked DRAM package, even though the stresses at each die are apparently different. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: This study aimed to further investigate the effects of agmatine on brain edema in the rats with middle cerebral artery occlusion (MCAO) injury using magnetic resonance imaging (MRI) monitoring and biochemical and histopathologic evaluation. Materials and methods: Following surgical induction of MCAO for 90min, agmatine was injected 5min after beginning of reperfusion and again once daily for the next 3 post-operative days. The events during ischemia and reperfusion were investigated by T2-weighted images (T2WI), serial diffusion-weighted images (DWI), calculated apparent diffusion coefficient (ADC) maps and contrast-enhanced T1-weighted images (CE-T1WI) during 3h–72h in a 1.5T Siemens MAGNETON Avanto Scanner. Lesion volumes were analyzed in a blinded and randomized manner. Triphenyltetrazolium chloride (TTC), Nissl, and Evans Blue stainings were performed at the corresponding sections. Results: Increased lesion volumes derived from T2WI, DWI, ADC, CE-T1WI, and TTC all were noted at 3h and peaked at 24h–48h after MCAO injury. TTC-derived infarct volumes were not significantly different from the T2WI, DWI-, and CE-T1WI-derived lesion volumes at the last imaging time (72h) point except for significantly smaller ADC lesions in the MCAO model (P<0.05). Volumetric calculation based on TTC-derived infarct also correlated significantly stronger to volumetric calculation based on last imaging time point derived on T2WI, DWI or CE-T1WI than ADC (P<0.05). At the last imaging time point, a significant increase in Evans Blue extravasation and a significant decrease in Nissl-positive cells numbers were noted in the vehicle-treated MCAO injured animals. The lesion volumes derived from T2WI, DWI, CE-T1WI, and Evans blue extravasation as well as the reduced numbers of Nissl-positive cells were all significantly attenuated in the agmatine-treated rats compared with the control ischemia rats (P<0.05). Conclusion: Our results suggest that agmatine has neuroprotective effects against brain edema on a reperfusion model after transient cerebral ischemia. [Copyright &y& Elsevier]