Texture investigation of copper interconnects with a different line width

To understand the effect of line width on textural and microstructural evolution of Cu damascene interconnect, three Cu interconnects samples with different line widths are investigated. According to x-ray diffraction (XRD) results, the (111) texture is developed in all investigated lines. Scattered {111}〈112〉 and {111}〈110〉 texture components are present in 0.18-μm-width interconnect lines, and the {111}〈110〉 texture was developed in 2-μm-width interconnect lines. The directional changes of the (111) plane orientation with increased line width were investigated by XRD. In addition, microstructure and grain-boundary character distribution (GBCD) of Cu interconnect were measured using electron backscattered diffraction (EBSD) techniques. This measurement demonstrated that a bamboo-like microstructure is developed in the narrow line, and a polygranular structure is developed in the wider line. The fraction of ∑3 boundaries is increased as the line width increases but is decreased in the blanket film. A new interpretation of textural evolution in damascene interconnect lines after annealing is suggested, based on the state of stress and growth mechanisms of Cu deposits.     

Color analysis of natural colorant‐dyed fabrics

Colors from naturally dyed fabrics recently have attracted both consumers and manufacturers in fashion markets. Even though color attributes of the fabrics have been partially observed in some literature, a data base of colors for natural colorants in fabrics needs to be established and the colors to be characterized according to systematic color notations and tones in order to relate the traditional natural colors to contemporary color communication systems. Therefore, a study was performed to investigate color characteristics for a given large set of natural colorants‐dyed fabrics based on the Munsell color notations, to analyze their tones with relation to the notation such as hue, value, and chroma, and finally to identify the effects of mordanting, an important coloring auxiliary, on the colorimetric properties of the fabrics. As a result, the dominant hue for a total of 350 naturally dyed fabrics was yellowish families followed by reddish and purplish ones in the Munsell notation owing to the use of leaves and plant as usual natural dyestuff, which confirms the limit of color hues of the fabrics. Color value for most of naturally dyed fabrics was generally higher whereas the chroma was lower, which means that most of colors for naturally dyed fabrics tended to be bright and weak shaded. Grayish, light grayish, and soft tones were the main tones of natural colorant‐dyed fabrics. All of hue, value, and chroma were found as being influenced by mordanting in that more particularly; iron mordanting was likely to cause the decrease of both value and chroma for most of naturally dyed fabrics. These results could provide a systematic color data for naturally dyed fashion fabrics and suggest a future direction of color development for them. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 148–157, 2008     

Effect of bamboo oil on antioxidative activity and nitrite scavenging activity

The purposes of this study were to investigate the effects of the bamboo oil on antioxidative activity and nitrite scavenging activity in vitro and in vivo. When the bamboo oil concentration was increased from 10 to 90 μL/mL, the DPPH scavenging rate increased from 15.6 to 98.2%. However, at bamboo oil concentrations above 110 μL/mL, it was not increased. The superoxide anion radical scavenging rate increased from 54.8 to 89.1% when the bamboo oil concentration increased from 110 to 150 μL/mL. When the bamboo oil was incubated for 20 h, the linoleic acid scavenging rate was approximately 91.2%, similar to that of ascorbic acid. The glutathione production using bamboo oil in vivo was 59.0 μM/g of liver, which was about 6.5-fold higher than that of the control. In the case of the activities of glutathione peroxidase and catalase, they were 16.8 U/mg of protein and 295 KU/mg of protein, respectively, approximately 5.6-fold higher and 3.0-fold higher than that of the control. The nitrite scavenging activity was increased from 60.1 to 93.9% at pH of 1.2 when the saturation time was increased from 2 months to 8 months. However, at more than 10 months of saturation, this level was not increased. These results suggest that the bamboo oil of Phyllostachys nigra var. henonis can be used in bioactive and functional materials.     

Efficient Load Balancing Algorithms for a Resilient Packet Ring

The resilient packet ring (RPR) is a data optimized ring network, where one of the key issues is on load balancing for competing streams of elastic traffic. This paper suggests three efficient traffic loading algorithms on the RPR. For the algorithms, we evaluate their efficiency via analysis or simulation.     

On Improving the Performance of an FIR ADM Digital Filter

In this paper we investigate methods of improving the performance of a finite impulse response (FIR) adaptive delta modulation digital filter (ADMDF). These include modification of the ADM step size adaptation algorithm, coefficient optimization, and the reduction of computational complexity. Compared to the FIR ADMDF of Sunwoo and Un [1], the improved filter yields better performance by approximately 4 dB and requires significantly less computation time.     

Temperature-compensation circuit techniques for high-density CMOSDRAMs

Temperature-compensation circuit techniques are presented for the CMOS DRAM internal voltage converter, the RC-delay circuit, and the back-bias generator, which do not need any additional process steps. The above-mentioned circuits have been designed and evaluated through a 16-Mb CMOS DRAM process. These circuits have shown an internal voltage converter (IVC) with an internal voltage temperature coefficient of 185 ppm/°C, and an RC-delay circuit with a delay time temperature coefficient of 0.03%/°C. As a result, a 6.5-ns faster RAS access time and improved latchup immunity have been achieved, compared with conventional circuit techniques     

Adhesion improvement of copper/epoxy joints

Copper oxides have been formed to improve the adhesive strength of copper/epoxy joints. Initial adhesive strength and durability of copper/epoxy joints were compared depending upon the type of oxides, black or red oxide. Although the initial adhesive strength of black oxide treated joints was worse than that of red oxide treated joints, the durability in acidic environment was better. In order to improve the durability of red oxide treated joints, 5-amino-indazole was applied to inhibit the corrosion of oxide layer in acidic medium. With the treatment of 5-amino-indazole, initial adhesive strength was increased by 50%, and durability was improved. The loci of failure for oxide treated joints were investigated with scanning electron microscope and X-ray photoelectron spectroscopy.