• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제34회 추계학술대회 개최
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• pp.179-185
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• 2001

High performance characteristics are required for rolling bearings and the various functions of bearing are greatly influenced by grease. Recently, higher performance is being demanded of rolling bearing greases for bearing lubrication. Four special greases with different composition such as lithium soap/ester oil, urea/ester oil, urea/ether oil and PTFE/fluorine oil were synthesized to compare the performance of these greases with that of the conventional lithium soap/mineral oil grease. The grease properties were investigated using a series of typical grease testing methods and grease life test. After the life test, the greases were charaterized by FTIR analysis and a microscope. And the iron amount in the greases was analyzed by AAS after ashing. The composition and manufacturing process determined the grease performance. The grease with a base oil of synthetic oil showed higher performance and the urea/ester oil and PTFE/fluorine oil showed about three times longer life as compared with conventional lithium grease.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권8호
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• pp.487-494
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• 2000

This paper describes the design, fabrication and experiments of surface-micromachined aluminum micromirror array with hidden pin-joints. Instead of the conventional elastic spring components as connection between mirror plate and supporting structure, we used pin-joint composed of pin and staples to support the mirror plate. The placement of pin-joint under the mirror plate makes large active surface area possible. These flexureless micromirrors are driven by electrostatic force. As the mirror plate has discrete deflection angles, the device can be ap;lied to adaptive optics and digitally-operating optical applications. Four-level metal structural layers and semi-cured photoresist sacrificial layers were used in the fabrication process and sacrificial layers were removed by oxygen plasma ashing. Static characteristics of fabricated samples were measured and compared with modeling results.

• 반도체디스플레이기술학회지
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• 제19권3호
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• pp.55-60
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• 2020

The hard mask photo-resist strip inspection system for the semiconductor wafer manufacturing process inspects the position of the circuit pattern formed on the wafer by measuring the distance from the edge of the wafer to the strip processing area. After that, it is an inspection system that enables you to check the process status in real time. Process defects can be significantly reduced by applying a tester that has not been applied to the existing wafer strip process, edge etching process, and wafer ashing process. In addition, it is a technology for localizing semiconductor process inspection equipment that can analyze the outer diameter of the wafer and the state of pattern formation, which can secure process stability and improve wafer edge yield.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.103-104
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• 2007

Nanometer-scaled polymer beads, such as polystyrene beads, were used as nanometer fabrication materials due to their some advantages such as self-assembled monolayer, nanometer scaled size and excellent compatibility with silicon based devices. Thus, the investigation on these properties of polymer beads was required. It is difficult to control the array of polystyrene beads on silicon substrate. In this study, we investigated the condition of selective array of polystyrene beads on nanometer-scaled hydrophilic surface which was obtained by APS coating. A tilting method was used to array the polystyrene beads selectively on the substrate. The polystyrene beads could be arrayed selectively by this method. From these results, we verified that there are possibilities to fabricate unique tools for the nanometer-scaled electrical devices.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2008년도 춘계학술발표논문집
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• pp.302-305
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• 2008

본 논문에서는 상압 플라즈마 방식이 적용된 반도체 에싱공정의 포토레지스트 에싱율을 향상시키기 위한 연구가 수행되었다. 웨이퍼 표면에 도포된 포토레지스트의 에싱율을 높이기 위하여 공정에 다구찌 기법을 적용하여 실험하였다. 유의한 인자를 파악하고 적합한 인자의 조합을 결정하여 에싱율 향상을 위한 효율적인 접근을 시도하였다. 이 연구는 상압플라즈마 방식이 적용된 에싱공정에서 개별 인자가 지니고 있는 시스템에 대한 기여율에 대하여 나타내었으며 또한 포토레지스트 에싱에 대한 플라즈마의 효용성을 보여준다.

• 한국식품과학회지
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• 제15권3호
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• pp.225-230
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• 1983

합리적(合理的)이고 경제적(經濟的)인 분해방법(分解方法)을 모색(摸索)하기 위해 고지방(高指肪) 함유식품(含有食品)인 생황석어(黃石魚)와 생멸치를 건조(乾燥)하여 분말(分末)로 한후 왕수처리법(王水處理法), 건식분해법(乾式分解法)과 $H_{2}SO_{4}-HNO_{3}$ 분해법(分解法)으로 전처리(前處理)하여 atomic absorption spectrophotometer를 통해 K, Na, Mg, Ca, Zn, Mn, Cu, Fe을 측정(測定)하였으며 그 결과는 다음과 같다. (1) 건식(乾式), 습식(濕式) 및 왕수처리법(王水處理法)에 의한 측정치(測定値) 중 황석어(黃石魚)에선 K, Na, Mn, Cu와 Fe의 함량(含量)이 분해법(分解法)에 따른 유의성(有意性)을 나타내지 않았고, 멸치에서는 K, Na, Mg, Cu의 함량(含量)이 세 분해법(分解法)에서 유의성(有意性)이 없었다. 반면에 Mg과 Zn(황석어)와 Mn과 Fe(멸치)는 분해법(分解法)에 따라 P< 5%의 유의성(有意性)을 보였고, Ca(황석어와 멸치)과 Zn(멸치)는 P< 1%의 높은 유의성(有意性)을 나타냈다. (2) 세 분해법(分解法)에 의한 측정치(測定直)의 유의적(有意的)인 차(差)를 근거로 모평균(母平均)을 추정(推定)한 결과(結果), 일반적으로 건식분해법(乾式分解法)에 의한 결과(結果)와 왕수처리법(王水處理法)에 의한 측정치(測定値)가 같은 수준효과(水準效果)를 나타냈고 재래식(在來式) 습식법(濕式法)은 모평균(母平均)이 가장 낮은 수준효과(水準效果)를 나타냈다. (3) 각(各) 측정치(測定値)와 표준편차(標準偏差)를 근거로 변이계수(變異係數) (coefficient of variation)을 구(求)해 본 결과(結果), 건식분해법(乾式分解法)이 가장 높은 변이계수(變異係數) 0.325였고, 왕수처리법(王水處理法)에 의한 측정치(測定値)가 습식법(濕式法)의 0.261보다도 낮은 0.195로 가장 낮은 변이계수(變異係數)를 보여 그 신뢰도(信賴度)를 높여 준다.

• Korean Chemical Engineering Research
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• 제43권1호
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• pp.27-32
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• 2005

본 연구에서는 다양한 공용매로 변형된 초임계 이산화탄소를 이용하여 웨이퍼 표면에 존재하는 이온주입 포토레지스트(IIP, ion-implanted photoresist) 및 잔류 불순물의 제거 공정을 97, 148, $200^{\circ}C$의 온도와 200, 300, 400 bar의 압력조건에서 수행하였다. 이온주입 포토레지스트는 순수 초임계 이산화탄소에 의해 제거되지 않았으나 팽윤(swelling)되는 것을 확인할 수 있었다. 또한, 단일 공용매 및 비양성자성 용매들의 혼합 공용매로 변형된 초임계 이산화탄소 시스템은 이온주입 포토레지스트를 팽윤시키나, 제거에 효과적이지 못하였다. 그러나 DMSO에 DIW가 혼합된 혼합 공용매(5%, v/v)로 변형된 초임계 이산화탄소 시스템은 $97^{\circ}C$, 200 bar의 온도, 압력 조건에서 30분 동안 세정 실험을 수행한 결과 이온 주입 포토레지스트의 제거에 효과적이었다(약 80%). 본 연구에서 사용된 혼합 공용매로 변형된 초임계 이산화탄소 시스템은 플라즈마 애싱(ashing) 및 산과 용매가 기본이 되는 습식 세정 방법의 대안으로서 화학액의 사용과 폐수를 감소시킬 수 있다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제1권2호
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• pp.132-139
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• 2001

We considered the uniformity of fabricated micromirror arrays by characterizing the fabrication process and calculating the appropriate driving voltages of micromirrors used as virtual photomask in maskless photolithography. The uniformity of the micromirror array in terms of driving voltage and optical characteristics is adversely affected by factors, such as the air gap between the bottom electrode and the mirror plate, the spring shape and the deformation of the mirror plate or torsion spring. The thickness deviation of the photoresist sacrificial layer, the misalignment between mirror plate and bottom electrode, the aluminum deposition condition used to produce the spring and the mirror plate, and initial mirror deflection were identified as key factors. Their importance lies in the fact that they are related to air gap deviations under the mirror plate, asymmetric driving voltages in left and right mirror directions, and the deformation of the Al sring or mirror plate after removal of the sacrificial layer. The plasma ashing conditions used for removing the sacrificial layer also contributed to the deformation of the mirror plate and spring. Driving voltages were calculated for the pixel operation of the micromirror array, and the non-uniform characteristics of fabricated micromirrors were taken into consideration to improve driving performance reliability.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권10호
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• pp.546-550
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• 2004

Two fabrication approaches are proposed to planarize the sacrificial layer over hollow structures. One is the photoresist filling method that makes use of photolithography, thermal curing and plasma ashing. The other is the lamination method that is applying pressure and temperature to the organic film over the hollow structures. The fabrication results are compared with those of CMP process. Trenches and cavities with various dimensions have been made for the porposed process. Upon measuring the planarization levels, they are dependent on planarization methods and the geometrical size of hollow structures. The photoresist filling method is so strongly dependent on the width and depth of trenches that we have problems to use it for large dimensional trenches. To the contrary, the flatness of sacrificial layer over the trenches was found to be almost independent of trench dimensions for the lamination method. A CMP process shows the most excellent results, but the fabrication is complicated and the access to it is not so easy. It is important to choose the proper planarization method by considering the required flatness levels, materials to be planarized, and connection between the planarization step and the previous or the following process of it.

• 한국진공학회지
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• 제5권2호
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• pp.113-118
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• 1996

Aligning a cathode tip at the center of a gate hole is important in gated filed emission devices. We have fabricated a silicon field emitter using a following process so that a cathode and a gate hole are automatically aligned . After forming silicon tips on a silicon wafer, the wafer was covered with the $SiO_2$, gate metal, and photoresistive(PR) films. Because of the viscosity of the PR films, a spot where cathode tips were located protruded above the surface. By ashing the surface of the PR film, the gate metal above the tip apex was exposed when other area was still covered with the PR film. The exposed gate metal and subsequenlty the $SiO_2$ layer were selectively etched. The result produced a field emitter in which the gate film was in volcano shape and the cathode tip was located at the center of the gate hole. Computer simulation showed that the volcano shape and the cathode tip was located at the center of the gat hole. Computer simulation showed that the volcano shape emitter higher current and the electron beam which was focused better than the emitter for which the gate film was flat.