• 한국정밀공학회지
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• 제20권2호
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• pp.25-32
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• 2003

Molding properties of etched surface pattern are presented. Injection molding has given attention on improving dimensional accuracy and productivity. However, the molding of etched surface pattern on plastic parts is not researched relatively for its additional values, which can meet design function and customer's attraction. Specimens, whose surface patterns are made by print-type etching, are investigated. The molding properties of surface pattern are estimated with roughness deviation of surface pattern on part and mold. The etching properties are related to physical properties of plastic materials and surface roughness of etched pattern. Also, flow mark and gate location can give influence on surface pattern molding. The experimental result can contribute to good molding of surface pattern in injection molding.

• Korea-Australia Rheology Journal
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• 제19권3호
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• pp.165-169
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• 2007

The light guide plate (LGP) of LCD-BLU (Liquid Crystal Display-Back Light Unit) is usually manufactured by forming numerous dots by etching process. However, the surface of those etched dots of LGP is very rough due to the characteristics of etching process, so that its light loss is relatively high due to the dispersion of light. Accordingly, there is a limit in raising the luminance of LCD-BLU. In order to overcome the limit of current etched-dot patterned LGP, micro-lens pattern was tested to investigate the possibility of replacing etched pattern in the present study. The micro-lens pattern fabricated by the modified LiGA with thermal reflow process was applied to the optical design of LGP. The attention was paid to the effects of different optical pattern type (i.e. etched dot, micro-lens). Finally, the micro-lens patterned LGP showed better optical qualities than the one made by the etched-dot patterned LGP in luminance.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.583-586
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• 2002

Molding properties of etched surface pattern are presented. Specimens, whose surface patterns are made by print-type etching, are investigated. The molding properties of surface pattern are estimated with roughness deviation of surface pattern on part and mold. The etching properties are related to physical properties of plastic materials and surface roughness of etched pattern. Also, flow mark and gate location can give influence on surface pattern molding. The experimental result can contribute to good molding of surface pattern in injection molding.

• 대한치과보철학회지
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• 제23권1호
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• pp.83-95
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• 1985

The purpose of this study was to evaluate microstructures on the etched surface of 11 base metal alloys for dental restorations and to observe the relationship between the etching pattern and beryllium. For this purpose, the following experiments were done; 11 base metal alloys were etched in (1) 10% $H_2SO_4$, (2) 10% $H_2SO_4$, 9 parts+methanol 1 part (3) Conc. $HNO_3$ 25%+glacial acetic acid 25%+$H_2O$ 50% (4) Conc. $HNO_3$ 5% (5) 2% glacial acetic acid added to Conc. $HNO_3$ 1% solution, with their etching conditions varied. Etched surface of alloys were examined under the scanning electron microscope. Results were as follows; 1. Almost all of Ni-Cr-Be alloys showed gooed etchd surface in $H_2SO_4$, solution, while some of those alloys which contains no beryllium showed good etched surface in $HNO_3$ solution. 2. Main components of etching solution can vary etching pattern of alloys. 3. Gamma prime phase relief, which can be found in all Ni-Cr-Be alloys, can't be found in any alloy that contains no beryllium.

• 한국산학기술학회논문지
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• 제10권11호
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• pp.3280-3286
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• 2009

본 논문에서는 미세 무광부식 패턴을 갖는 HD Switch Panel 자동차 부품을 개발하는 것으로, 제품 디자인을 통해 금형을 설계, 제작하였다. 최적화된 금형 제작을 위하여 CAE(Computer Aided Engineering)해석을 통하여 사출성형 공정에서 나타날 수 있는 문제점과 부품의 수축 변형을 정량적으로 예측하였다. 그리고, 금형표면의 가열온도와 실제 금형온도를 비교함으로써 공정변수 조절을 통해 사출성형조건의 최적화도 달성할 수 있었다. 한편, 순간금형표면가열방식을 이용한 성형기술인 E-MOLD를 적용하여 자동차 내장부품용 HD Switch Panel 사출성형품을 제작하였고, 전자현미경과 원자현미경을 이용한 표면 평가 및 광택도 측정을 통하여 무광부식 패턴의 전사율 향상으로 인한 무광 특성이 향상됨(2.5이상$\to$1.5~1.7)을 확인하였다.

• 한국재료학회지
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• 제27권8호
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• pp.397-402
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• 2017

We used an etching process to control the line-width of screen printed Ag paste patterns. Ag paste was printed on anodized Al substrate to produce a high power LED. In general, Ag paste spreads or diffuses on anodized Al substrate in the process of screen printing; therefore, the line-width of the printed Ag paste pattern increases in contrast with the ideal line-width of the pattern. Smudges of Ag paste on anodized Al substrate were removed by neutral etching process without surface damage of the anodized Al substrate. Accordingly, the line-width of the printed Ag paste pattern was controlled as close as possible to the ideal line-width. When the etched Ag paste pattern was used as a seed layer for electroless Ni plating, the line width of the plated Ni film was similar to the line-width of the etched Ag paste pattern. Finally, in pattern formation by Ag paste screen printing, we found that the accuracy of the line-width of the pattern can be effectively improved by using an etching process before electroless Ni plating.

• 대한소아치과학회지
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• 제10권1호
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• pp.85-93
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• 1983

In one group that tested for the effects of grinding and etching on the deciduous teeth, S.E.M. examination on the ground or unground labial surface of deciduous maxillary central incisors were made after etching procedure with 40% phosphoric acid for 60 secs., 120 secs., 180 sees. each. In another group that tested for the degree of resin penetration to the ground and etched deciduous teeth, composite resin application was done to the ground deciduous maxillary central incisors that had been acid-etched for 30 secs., 60 secs., 90 sees., 120 sees., 180 secs. each. The tooth-resin specimens were cut at the middle 1/3 of the crown by 2mm thickness, and the adjacent tooth materials were demineralized by 10% hydrochloric acid, the author observed the tags of the resin replica with S.E.M.. Following results were obtained. 1. After 40% phosphoric acid etching, the unground deciduous enamel surface showed various types of etching pattern. 2. For the formation of regular micropores on deciduous enamel surface by acid etching with 40% phosphoric acid, the time over 120 secs. should be requested. 3. After 40% phosphoric acid etching, the ground deciduous enamel surface showed the same etching pattern that has been a preferential removal of prism peripheries despite different etching time. 4. On the ground group that etched over 60 secs. to 180 secs., the length of tags was $5{\mu}m$ to $8{\mu}m$, with a mean of $7{\mu}m$.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.398-400
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• 1998

In this paper, the etching studies for n-GaN were carried out using the wet chemical, the photo-enhanced-chemical, and the electro-chemical etching methods. The experimental results show that n-GaN is etched in diluted NaOH solution at room temperture and the etched thickness of NaOH and electron concentrations. Te etching rate of n-GaN samples with n.simeq.1*10$^{19}$ cm$^{-3}$ were used to compare the photo-enhanced-chemical etching with the electrochemical etching methods. The removed thickness was 680.angs./25min by the electrochemical etching methods. The removed thickness was 680 .angs./25min by the electrochemical etching method ad 784.angs./25min by the photoenhanced-chemical etching method. The patterns are 100.mu.m*100.mu.m rectangulars covered with SiO$_{2}$film. It is shown that the profile of etched side-wall of the pattern is vertical without dependance of the n-GaN orientations.

• 한국전기전자재료학회논문지
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• 제22권8호
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• pp.654-658
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• 2009

For investigation of surface leakage currrent of AlGaN/GaN heterostructures through etched GaN buffer surface and mesa wall, three kind of surface-leakage-test-patterns were fabricated. and we measured the surface leakage current of each patterns. In result of our work, the surface leakage current of pattern of which Schottky contact is formed on etched mesa wall is the largest. the leakage current through schottky contact on etched mesa wall is predominant in AlGaN/GaN heterostructures.

• 정보통신설비학회논문지
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• 제2권1호
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• pp.52-62
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• 2003

본 논문에서는 그라운드 판에 주기적으로 에칭된 원으로 구성된 Photonic Bandgap(PBG) 여파기가 광대역 하모닉 성분을 제거할 수 있음을 보인다. FDTD법과 제작, 실험을 통해 얻은 결과를 이용하여 PBG 구조의 특성을 분석해 보았고, FDTD법은 다양한 3차원 구조를 시뮬레이션을 할 수 있고 광대역의 주파수 응답을 볼 수 있다. 분석 결과는 에칭된 원들을 2차원으로 배열한 경우와 일렬로 배열한 경우 모두 똑같은 결과가 나오는 것을 나타냈다. 그리고 에칭된 원과 원 사이의 공진기의 특성을 필드패턴을 통해서 알아 보았고, 에칭된 원들의 수 n, 에칭된 원의 반지름 r과 주기 a의 변화에 따른 주파수의 특성을 보았다.