• 제목/요약/키워드: Mechanical Engineers

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연마불균일도에 영향을 미치는 패드 표면특성에 관한 연구 (The Effect of Pad Surface Characteristics on Within Wafer Non-uniformity in CMP)

  • 박기현;박범영;정재우;이현섭;정석훈;정해도;김형재
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.38-39
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    • 2005
  • We have investigated the effect of the pad surface characteristics such as roughness, groove density and wear of pad on within wafer non-uniformity(WIWNU) in chemical mechanical polishing(CMP). We found that WIWNU increases as pad surface roughness($R_{pk}$; Reduced peak height) increases in an early stage of polishing. But after polishing time goes to a certain extent, WIWNU decreases as uniformity of pad surface roughness. Also, groove of pad has effect on relative pad stiffness although original mechanical properties of pad are unchanged by grooving. WIWNU decreases as relative pad stiffness decreases. In addition, conditioning process causes non-uniform wear of pad during in CMP. The profile of pad wear has a significant effect on WIWNU.

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MEMS CMP에서 모니터링 시스템을 이용한 슬러리 특성 (The Surry Characteristic Using Monitoring System in MEMS CMP)

  • 박성민;정석훈;박범영;이상직;정원덕;장원문;정해도
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.573-574
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    • 2006
  • The planarization technology of Chemical-mechanical polishing(CMP), used for the manufacturing of multi-layer various material interconnects for Large-scale Integrated Circuits (LSI), is also readily adaptable as an enabling technology in MicroElectroMechanical System (MEMS) fabrication, particularly polysilicon surface micromachining. However, general LSI device CMP has partly distinction aspects, the pattern scale and material sorts in comparison with MEMS CMP. This study performed preliminary CMP tests to identify slurry characteristic used in general IC device. The experiment result is possible to verify slurry characteristic in MEMS structure material.

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무기체계의 상세설계 단계에 적용을 위한 한국형 정비도 예측 S/W 개발 (Development of Korean Maintainability-Prediction Software for Application to the Detailed Design Stages of Weapon Systems)

  • 권재언;김수주;허장욱
    • 한국기계가공학회지
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    • 제20권10호
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    • pp.102-111
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    • 2021
  • Maintainability is a major design parameter that includes availability as well as reliability in a RAM (reliability, availability, maintainability) analysis, and is an index that must be considered when developing a system. There is a lack of awareness of the importance of predicting and analyzing maintainability; therefore, it is dependent on past-experience data. To improve the utilization rate, maintainability must be managed as a key indicator to meet the user's requirements for failure maintenance time and to reduce life-cycle costs. To improve the maintainability-prediction accuracy in the detailed design stage, we present a maintainability-prediction method that applies Method B of the Military Standardization Handbook (MIL-HDBK-472) Procedure V, as well as a Korean maintainability-prediction software package that reflects the system complexity.

클러스터링 알고리즘을 이용한 배관의 부식 상태 분류 (State Classification of the Corrosion of Pipes Using a Clustering Algorithm)

  • 천강민;신건호;허장욱
    • 한국기계가공학회지
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    • 제21권7호
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    • pp.91-97
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    • 2022
  • Pipes transport and supply fuel in various categories; however, corrosion occurs because of the external environment, impurities are mixed in the fuel, and substances leak to the outside, which can lead to serious accidents. Therefore, in this study, inspection equipment using a laser scanner was manufactured to classify conditions according to the degree of corrosion of the outer wall of the pipe, and the corrosion height and maximum value of the pipe were obtained from the surface information. Using the k-means method, it was classified into four states, and the standard of the average height and maximum height of corrosion for each state was derived.

내수성 및 기계적 물성이 향상된 열처리된 폴리비닐알코올/셀룰로오스 나노결정 필름 (Heat-Treated Polyvinyl Alcohol/Cellulose Nanocrystal Film with Improved Mechanical Properties and Water Resistance)

  • ;이봉기
    • 한국기계가공학회지
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    • 제20권11호
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    • pp.1-8
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    • 2021
  • In this study, the water resistance and mechanical properties of heat-treated polyvinyl alcohol (PVA)/cellulose nanocrystal (CNC) films were investigated. PVA is the most commonly used synthetic biodegradable polymers owing to its excellent properties. However, the water/moisture sensitivity and relatively poor mechanical properties of PVA limits its applications. Although heat treatment is a conventionally used method to improve the mechanical strength and water resistance of PVA, the effectiveness of this method is insufficient. Therefore, CNC was used to further improve the mechanical properties and water resistance of the heat-treated PVA film. PVA/CNC nanocomposites containing CNC contents of 0, 1, 3, 5, and 10 wt% were fabricated using solvent casting and subsequent heat treatment. The mechanical properties and water resistance of PVA/CNC films were significantly improved. The tensile strength and wet strength of the PVA/CNC film with a CNC content of 5 wt% (PVA/CNC 5%) were 184.5% and 136.0% higher than those of the untreated PVA, respectively. In addition, the water absorption and solubility of PVA/CNC 5% were 56.6% and 68.2% lower than those of the untreated PVA.

레이저 변위 센서를 활용한 배관 표면 상태분류 (Classification of the Rusting State of Pipe Using a Laser Displacement Sensor)

  • 천강민;신백천;신건호;고정일;이준혁;허장욱
    • 한국기계가공학회지
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    • 제21권5호
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    • pp.46-52
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    • 2022
  • Although pipe performs various functions in industrial sites and residential spaces, if it is damaged due to corrosion caused by the external environment, it may cause equipment failure or a major accident. For this reason, various studies for safety management are being conducted, but studies on detecting corrosion or cracks on the pipe surface using a laser displacement sensor have hardly been conducted. Therefore, in this study, the corrosion degree of the pipe surface was compared and classified into 4 corrosion conditions, and inspection equipment using a laser scanner was manufactured. The corrosion height was calculated from the four surface data obtained from the measuring equipment and applied to various CNN algorithms, and 91% accuracy was obtained during training using the Modified VGGNet16 code with reduced number of parameters.

정밀도 성능평가를 위한 3차원 측정기 수치모델 개발 (Development of Numerical CCM in Pursuit of Accuracy Assessment for Coordinate Measuring Machines)

  • 박희재
    • 대한기계학회논문집A
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    • 제20권3호
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    • pp.945-959
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    • 1996
  • In this paper, a comprehensive computer model is described which can be used to generate the volumetric error map combining the machine parametric errors and the measurement prove error, for most types of CMMs and axis configurations currently in use.

Bending Strain Effect on the Critical Current of Jointed BSCCO Tapes

  • Shin, Hyung-Seop;Dedicatoria, Marlon
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
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    • pp.217-217
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    • 2009
  • In this study, the effect of bending strain on the transport property and critical current of lap and butt-jointed BSCCO tapes have been investigated. The samples were joined using a mechanically controlled jointing procedure. In order to ensure a uniform pressure application at the joint part, a single point contact has been devised and also to achieve a uniform thickness at the joint interface.

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크랙의 부분 또는 완정닫힘에 관한 열 및 기계적 응력해석 (Thermo-Mechanical stress analysis for partial or entire crack closure)

  • ;이강용
    • 대한기계학회논문집
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    • 제5권3호
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    • pp.193-198
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    • 1981
  • Muskhelishvili 의 복소수방법에 의해 일반적 하중 즉 열 및 기계적 하중을 받는 무한 탄성체내에 공동을 가정하고 그 주위의 응력 및 변위를 유도하였다. 선형트랙(line rack)이 부분적으로 또는 완정히 닫힐 임계하중조건과 그때의 응력세기 계수 (stress intensity factor)를 McClintork와 Walsh 의 크랙닫힘에 관한 결정에 기초를 두고 해석학적으로 유도하였다.

실시간 시뮬레이션을 위한 병렬적분 (Parallel Integration for Real-Time Simulation)

  • 이운성
    • 한국자동차공학회논문집
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    • 제2권1호
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    • pp.106-115
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    • 1994
  • A parallel integration approach is proposed for real-time simulation of controlled mechanical systems. The proposed approach, which employs the dual-rate integration method in a parallel computing environment, is developed to deal with stiffness and high frequency characteristics of the controlled mechanical systems effectively. Numerical experiments are performed to demonstrate the effectiveness of the approach in shared memory multiprocessors, Alliant FX/8 and Alliant FX/80.

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