• 제목/요약/키워드: 2-dimensional material

검색결과 1,204건 처리시간 0.024초

체커보드 형상을 가진 3차원 복합소재의 연결도와 전도율 (Connectivity and Conductivity of a Three-Dimensional Checkerboard-Shaped Composite Material)

  • 김인찬
    • 대한기계학회논문집B
    • /
    • 제28권2호
    • /
    • pp.189-198
    • /
    • 2004
  • We consider the problem of whether the three-dimensional checkerboard has the connectivity. For this purpose, we first consider the problem of determining the effective conductivity of a checkerboard-shaped composite material by the Brownian motion simulation method. Specifically, we use the efficient first-passage-time technique. Simulation results show that the effective conductivity of the three-dimensional checkerboard increases faster than the two-dimensional counterpart as the contrast between the phase conductivities increases. This implies that the three-dimensional checkerboard's connectivity is stronger than the two-dimensional checkerboard's and thus each phase material of the three-dimensional checkerboard is more likely to be connected than not to be connected.

1,2차 모델링을 이용한 Ar RF 플라즈마의 응답 특성 (The Properties of Ar RF Plasma Using 1- and 2-dimensional Model)

  • 박용섭;정해덕
    • 한국전기전자재료학회논문지
    • /
    • 제14권8호
    • /
    • pp.622-628
    • /
    • 2001
  • We developed 1- and 2-dimensional fluid model for the analysis of a capacitively coupled Ar RF(Radio Frequency) glow discharge. This discharge is in pure Ar gas at the pressure 100[mTorr], frequency 13.56[MHz] and voltage amplitude 120[V}. This model is based on the equations of continuity and electron energy conservation coupled with Poison equation. 2-dimensional model is simulated on the condition of GEC(Gaseous Electronic Conference cell). The geometry of the discharge chamber and the electrodes used in the model is cylindrically simmetric; tow cylinders for the electrodes are surrounded by the grounded chamber. It is shown that 1-dimensional model is very useful on the understanding of RF glow discharge property and of the movement of charged particles. 2-dimensional model predicts off-axis maximum structure as in the experiments and has the results in qualitatively and quantitatively good agreement with the experiments. Effects of dc self-bias voltage, guard ring and reactor geometry is discussed.

  • PDF

부분 가열된 무한 경사기능재료 판의 2차원 비정상 열응력 (Two-dimensional Unsteady Thermal Stresses in a partially heated infinite FGM Plate)

  • 김귀섭
    • 한국항공운항학회지
    • /
    • 제15권2호
    • /
    • pp.9-17
    • /
    • 2007
  • A Green's function approach based on the laminate theory is adopted for solving the two-dimensional unsteady temperature field and the associated thermal stresses in an infinite plate made of functionally graded material (FGM). All material properties are assumed to depend only on the coordinate x (perpendicular to the surface). The unsteady heat conduction equation is formulated into an eigenvalue problem by making use of the eigenfunction expansion theory and the laminate theory. The eigenvalues and the corresponding eigenfunctions obtained by solving an eigenvalue problem for each layer constitute the Green's function solution for analyzing the two-dimensional unsteady temperature. The associated thermoelastic field is analyzed by making use of the thermal stress function. Numerical analysis for a FGM plate is carried out and effects of material properties on unsteady thermoelastic behaviors are discussed.

  • PDF

전극형상을 고려한 수정진동자 해석 기법 연구 (FEM analysis of Quartz oscillator considering dimensions of electrode)

  • 박승배;김종정;이덕훈;김태성
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
    • /
    • pp.543-546
    • /
    • 2001
  • So far, the design methods of quartz crystal resonator have been developed. Recently, as the electronic package and semiconductor modules become smaller, the need to minimize the sizes of crystal components grows larger. but Minimizing crystal plate sizes has limitations because its temperature-frequency characteristics is worse and unwanted resonances occur. so appropriate design of electrode size and crystal plates is necessary. In this palter, Two-dimensional governing equations for electroded piezoelectric crystal plates with general symmetry have been solved from deduced equations from three-dimensional equations of linear piezoelectricity in most cases. In practice, electroded piezoelectric crystal plates have three-dimensional geometry, so simplified 2-dimensional equations and 2-D modeling are insufficient for explaining its resonance modes and characteristics. So, three-dimensional FEM(finite element method) analysis is done and its effectiveness is verified from analyzing practical crystal resonator model.

  • PDF

CMOS 공정을 이용한 2차원 SSIMT의 특성 (Characteristics of the 2-D SSIMT using a CMOS Process)

  • 송윤귀;류지구
    • 한국전기전자재료학회논문지
    • /
    • 제20권8호
    • /
    • pp.697-700
    • /
    • 2007
  • A novel 2-Dimensional Suppressed Sidewall Injection Magnetotransistor (SSIMT) with high linearity has been fabricated on the standard CMOS technology and experimentally verified. The novel 2-Dimensional SSIMT overcomes the restriction of the standard CMOS technology. Experimental results of the fabricated 2-Dimensional SSIMT show that the variation of each collector output currents are extremely linear as a function of magnetic field from -200mT to 200mT at $I_B = 1 mA,\;V_{CE} = 5 V\;and\;V_{SE} = 5 V$. The relative sensitivity shows up to 13 %/T. The measured nonlinearity of the fabricated device is about 0.9%.

이차원 반도체 소재를 이용한 투명 태양전지 특성에 관한 연구 (Transparent Photovoltaic Device using Two-dimensional Transition-metal Dichalcogenides)

  • 좌태헌;현철민;김민식;이혁주;안지훈
    • 한국표면공학회지
    • /
    • 제49권2호
    • /
    • pp.186-190
    • /
    • 2016
  • In this study, we fabricated the transparent photovoltaic device using 2-dimensional transition-metal dichalcogenides and investigated the transparency and photovoltaic characteristics. P-n heterojunction was formed by mechanical exfoliation and aligned transfer method on the transparent sheet using n-type $MoS_2$ and p-type $WSe_2$. Our transparent photovoltaic device exhibited the open-circuit voltage of ~ 0.15 V and the short-circuit current of 0.48 nA under illumination of white light.

열산화 공정 시뮬레이션을 위한 3차원 적응 메쉬 생성기 제작에 관한 연구 (Three Dimensional Adaptive Mesh Generator for Thermal Oxidation Simulation)

  • 윤상호;이제희;윤광섭;원태영
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
    • /
    • pp.48-51
    • /
    • 1995
  • We have developed the three dimensional mesh generator for three dimensional process simulation using the FEM(Finite Element Method). Tetrahedron element construct the presented three dimensional mesh, which is suitable for the simulation of three dimensional behavior of the LOCOS. The simulation of thermal oxidation is one of the problem in scale downed semiconductor processes. As three dimensional simulators use the huge size of the memory, we use the efficient method that generates the new nodes inside the growing oxide and removes the nodes nearby the SiO2/Si interface in silicon. The resented three dimensional mesh generator was designed to be used in various process simulations, for instance thermal oxidation, silicidation, nitridation, ion implantation, diffusion, and so on.

  • PDF

2차원적(次元的)인 직격자(直格子)와 역격자간(逆格子間)의 상호관계(相互關係) (Interrelation between Two-Dimensional Direct and Reciprocal Lattices)

  • 김영상;고재중;강상욱;한원식;서일환;김진규;김윤중
    • 한국결정학회지
    • /
    • 제17권1호
    • /
    • pp.1-5
    • /
    • 2006
  • 2차원적(二次元的)인 직격자(直格子)와 역격자(逆格子)의 기본(基本) vectors를 정의(定義)하고 이들 간(間)에 존재(存在)하는 여러 가지 상호관계(相互關係)를 유도(誘導)한 후(後) $\vec{d^*}(hk)//direction\;of\;(hk),\;d(hk)=1/d^*(hk),\;[uv]$ 방향(方向)에 속(屬)한 (hk)면(面)들, 그리고 이차원적(二次元的)인 4가지 격자(格子)들의 면적(面積) 및 면간건리등(面間距離等)의 계산법(計算法)을 제시(提示)하였다.

액정박막에서의 2차원 상전이 (Two dimensional Phase Transition of Liquid Crystal Film)

  • 정치섭;;김만원
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1993년도 춘계학술대회 논문집
    • /
    • pp.119-121
    • /
    • 1993
  • Two dimensional phase transition and three dimensional propagation of layer structures of liquid crystal film are investigated by using surface second harmonic generation method. We have found a distinctive first order phase transition between a monolayer phase and a stable 3-layer phase of 8CB liquid crystal film.

  • PDF