• JSTS:Journal of Semiconductor Technology and Science
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• 제6권3호
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• pp.169-174
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• 2006

In this work, we demonstrate a novel compact mechanical beam steering transmitter based on a direct vertical integration of a 2-D MEMS-based mechanical beam steering antenna with a VCO on a single silicon platform. By eliminating the long feed lines and waveguide metal blocks, the radiation pattern has been improved vastly, resulting in an almost ideal pattern at every scan angle. The losses incurred by the feed lines and phase shifters are also eliminated, which allows the transmitter to be implemented using only a single VCO. The system complexity has been greatly reduced with a total module size of only 1.5 cm ${\times}$ 1.5 cm ${\times}$ 0.4 cm. This work demonstrates that RF MEMS can be a key enabling technology for high-level integration.

• 전자공학회논문지D
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• 제34D권12호
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• pp.76-82
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• 1997

Chemical mechanical polishing (CMP) has become widely accepted for the planarization of multi-interconnect structures in semiconductor manufacturing. However, perfect planarization is not so easily ahieved because it depends on the pattern sensitivity, the large number of controllable process parameters, and the absence of a reliable process model, etc. In this paper, we realized the planarization of deposited oxide layers followed by metal (W) polishing as a replacement for tungsten etch-back process for via formation. Atomic force microscope (AFM) is used for the evaluation of pattern topography during CMP. As a result, AFM evaluation is very attractive compared to conventional methods for the measurment of planarity. mOreover, it will contribute to analyze planarization characteristics and establish CMP model.

• 건축역사연구
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• 제27권1호
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• pp.7-16
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• 2018

Meoricho of Dancheong is a pattern that placed at the end of each elements. We call Dancheong which has Meoricho Moro-dancheong. Meorico is the pattern comes from the metal ornaments of ancient architecture. The most primitive forms of Meoricho is Saw-toothed Design. Since the influence of Buddhism in the Northern Wei dynasties Saw-toothed Design have changed Tied lotus Design. Tied lotus Design of the Unified Silla it becames Gak-yeop Design and Yeo-ui-doo Design Meoricho in Goryeo Dynasty. Since Goryeo Dynasty there's been great and small variations in the internal composition of Meoricho, but the outline has maintained as it was. Therefore the completed form of the outline of Meoricho could be regarded as the one that was formed in Goryeo Dynasty.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.167-171
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• 1996

Chemical mechanical polishing (CMP) has become widely accepted for the planarization of multi-interconnect structures in semiconductor manufacturing. However, perfect planarization is not so easily achieved because it depends on the pattern sensitivity, the large number of controllable process parameters, and the absence of a reliable process model, etc. In this paper, we realized the planarization of deposited oxide layers followed by metal (W) polishing as a replacement for tungsten etchback process for via formation. Atomic force microscope (AFM) is used for the evaluation of pattern topography during CMP. As a result, AFM evaluation is very attractive compared to conventional methods for the measurement of planarity. Moreover, it will contribute to analyze planarization characteristics and establish CMP model.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.181-184
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• 2014

Loose Parts Monitoring System(LPMS) monitors loosened or detached parts and foreign parts inside the pressure boundary of a reactor coolant system (RCS). It is difficult to discriminate valid signal from LPMS alarms at full power since the signal pattern by thermal shocks and structure friction are similar to those by loose metal impacts. In addition, It is more difficult to discriminate the impact signals induced by the rod driving, sensor hard-line movement and loosened component since they have similar frequency characteristics with valid signals. This paper classifies the signal patterns by analyzing actual LPMS signal captured during nuclear power plant operation.

• Preventive Nutrition and Food Science
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• 제11권3호
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• pp.237-242
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• 2006

The pattern of volatile emissions from white ginseng powders (WGP) that were treated with selected preservatives was investigated during 5-months of storage (at -10 and $25^{\circ}C$) by an electronic nose system equipped with 12 metal-oxide sensors. WGP were treated with gamma radiation at 5 kGy, commercial methyl bromide (MeBr), and phosphine fumigations. Electronic nose differentiated the volatile patterns of the WGP with each different preservative treatment. In addition, each volatile pattern was affected by both storage time (1, 2 and 5 months) and temperature (-10 and $25^{\circ}C$). After 5-months of storage, the least change of volatile patterns was observed from WGP fumigated with phosphine at $-10^{\circ}C$. The result also showed that volatile changes in WGP were much more affected by storage time than by storage temperature.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권5호
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• pp.199-204
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• 2002

In order to recognize the deterioration of insulation system by partial discharge (PD), the characteristics of PD patterns which are occurring at the interface between epoxy and rubber materials in extra high voltage cable joints, have been investigated. The artificial defects such as voids, metal particles, insulation fiber and water impregnated insulation fiber are planted between the interfaces. A high frequency partial discharge detection system was used for measuring PD signals. An analysis of the PD patterns is focused on the shape of PD pattern, phase, width and time-dependence for each artificial defect. The PD Patterns in each defect show the different behaviors and it is suggested that the precise discrimination of PD patterns could be used for the diagnosis of deterioration in the insulation systems.

• Journal of information and communication convergence engineering
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• 제3권1호
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• pp.28-32
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• 2005

In this paper, we propose a novel test method to effectively detect hard and soft faults in CMOS 2-stage op-amps. The proposed method uses a very high frequency sinusoidal signal that exceeds unit gain bandwidth to maximize the fault effects. Since the proposed test method doesn't require any complex algorithms to generate the test pattern and uses only a single test pattern to detect all target faults, therefore test costs can be much reduced. The area overhead is also very small because the CUT is converted to a unit gain amplifier. Using HSPICE simulation, the results indicated a high degree of fault coverage for hard and soft faults in CMOS 2-stage op-amps. To verify this proposed method, we fabricated a CMOS op-amp that contained various short and open faults through the Hyundai 0.65-um 2-poly 2-metal CMOS process. Experimental results for the fabricated chip have shown that the proposed test method can effectively detect hard and soft faults in CMOS op-amps.

• 한국정밀공학회지
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• 제23권8호
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• pp.203-210
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• 2006

This paper focuses on the development of RT technology suitable for manufacturing a small quantity of metal prototype of a precise part from an RP master. Dimensional accuracy and surface roughness are evaluated from Thermojet part of a 3D printer, and effective post-processing method is introduced. Investment casting is done using a prototype built from 3D printer as a wax pattern. Ceramic shell investment casting technique is developed to build a prototype with materials mostly wanted. Also, experimental result shows this research is very useful in manufacturing of a small quantity of functional part or a test part of a specific material.

• 한국표면공학회지
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• 제32권3호
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• pp.244-248
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• 1999

Photoelectrodeposition of copper on semiconductive B-doped diamond films was investigated. There are cleasr morphology differences between photodeposited copper and electrodeposited copper. Photoelecrodeposition proceeded as uniform 2-dimensional growth. On the other hand electrodeposition proceeded as scarce random deposition. By applying this effect we have succeeded in forming a conductive pattern on semiconductive B-doped diamond with the aid of a photo-mask. And it was suggested that the surface reforming caused by photoelectrochemical process could be easily detected by the following metal (copper) deosition method, which is demonstrated as 'Diamond photographic phenomenon'.