• Journal of the Microelectronics and Packaging Society
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• v.25 no.3
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• pp.7-12
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• 2018

The effects of Ru deposition temperature and post-annealing conditions on the interfacial adhesion energies of atomic layer deposited (ALD) Ru diffusion barrier layer and Cu thin films for the advanced Cu interconnects applications were systematically investigated. The initial interfacial adhesion energies were 8.55, 9.37, $8.96J/m^2$ for the sample deposited at 225, 270, and $310^{\circ}C$, respectively, which are closely related to the similar microstructures and resistivities of Ru films for ALD Ru deposition temperature variations. And the interfacial adhesion energies showed the relatively stable high values over $7.59J/m^2$ until 250h during post-annealing at $200^{\circ}C$, while dramatically decreased to $1.40J/m^2$ after 500 h. The X-ray photoelectron spectroscopy Cu 2p peak separation analysis showed that there exists good correlation between the interfacial adhesion energy and the interfacial CuO formation. Therefore, ALD Ru seems to be a promising diffusion barrier candidate with reliable interfacial reliability for advanced Cu interconnects.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.796-805
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• 2000

A 30GHz band low noise amplifier module, which has linear gain of 30dB and noise figure of 2.6dB, for 30GHz satellite communication transponder was developed by use of MMIC and thin film MIC technologies. Two kinds of MMIC circuits were used for the low noise amplifier module, the first one is ultra low noise MMIC circuit and the other is wideband and high gain MMIC circuit. The pHEMT technology with 0.15$mu extrm{m}$ of gate length was applied for MMIC fabrication. Thin film microstrip lines on alumina substrate were used to interconnect two MMIC chips, and the thick film bias circuit board were developed to provide the stabilized DC bias. The input interface of the low noise amplifier module was designed with waveguide type to receive the signal from antenna directly, and the output port was adopted with K-type coaxial connector for interface with the frequency converter module behind the low noise amplifier module. Space qualified manufacturing processes were applied to manufacture and assemble the low noise amplifier module, and space qualification level of environment tests including thermal and vibration test were performed for it. The developed low noise amplifier was measured to show 30dB of minimum gain, $\pm$0.3dB of gain flatness, and 2.6dB of maximum noise figure over the desired operating frequency range from 30 to 31 GHz.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.62-75
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• 2017

This study analyzes the multiple effects of the following three aspects of waterscape facilities within apartment complexes: planning/designing, maintenance/management, and use of the facilities and suggests primary documents that will be fundamental for the methods to accelerate the implementation of waterscape facilities. A survey and analysis was conducted among a few of the most representative private apartment complexes in Seoul in accordance with the management and operation of waterscape facilities. The analysis used frequency analysis, descriptive statistics, reliability test, t-test, and PLS regression analysis. The research findings are as follows: first, the degree of use of waterscape facilities was found to be low regardless of the levels of operation, but residents' preference for the facilities was shown to be high, thus indicating there are still high expectations on the part of residents. Second, regardless of whether the facilities are being operated efficiently, the two items of location and display method under the section of planning and designing and the two items of aptitude and convenience under the section of use were found to positively affect the operation and use of waterscape facilities. Particularly, the item of freshness, cleanliness was shown to be directly and indirectly correlated with obsolescence, administration costs, and noise, which negatively affect the operation. Third, it was found that the administration costs itself that had been shown as the most negative factor of operating landscaping facilities in previous research did not cause problems in the residential area where the facilities are not operated efficiently. The finding suggests that the administration costs do not matter but that in the case of experience- and entertainment-typed facilities that residents want, they are linked to problems that do not introduce the desired facilities. Fourth, it was found that various aspects of planning, designing, maintaining, and using facilities interconnect and affect one another in the process of operating and using waterscape facilities resulting in the need to have a comprehensive approach to these three factors of planning, design, maintenance, management, and utilization. This study proposes that the needs and values of residents should be reflected to activate the introduction of landscaping facilities in the apartment complexes.