• Title/Summary/Keyword: TEM Journal

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반도체시료의 TEM 박편제작기술에 대한 연구

  • Baek, Mun-Cheol;Cha, Joo-Yeon;Cho, Kyung-Ik;Kwon, Oh-Joon
    • ETRI Journal
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    • v.10 no.3
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    • pp.212-220
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    • 1988
  • 투과전자현미경(TEM)의 관찰을 위한 반도체 시료의 박편제작기술에 대하여 언급하였다. 전자선을 투과할 수 있는 얇은 두께의 시편을 제작하는 일은 금속이나 생물학적인 재료에 비하여 반도체의 경우 많은 어려움이 따르며 특히 잘 부서지기 쉬운 특성 때문에 취급에 많은 주의를 요한다. 반도체를 대상으로 하여 일반적으로 사용되는 박편 제작기술에 대해 그 특성과 장단점 등을 조사하였다.

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Input impedance analysis of the coaxial to W/G type devices (동축전송선로에 연결된 도파관형 소자의 입력 임피던스 해석)

  • 이평화;천창율;신판석
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.11
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    • pp.9-19
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    • 1997
  • By noticing that most waveguide devices were connected to power source through coaxial line, three dimentional finite element analysis using TEM mode incident was tried. When tEM mode was used, being dissimilar to TE$_{10}$ mode incident, analysis model of TEM mode incident has almost the same geometry with real products. Therefore, the degree of trust about analysis result is improved. Reflection coefficients of coaxial line, W/G adaptor, magnetron obtained by simulation was compared with experimental results.

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An Investigation of the Transformation Sequence from Pyropyllite to Mullite by EF-TEM (EF-TEM을 이용한 납석-뮬라이트의 상변이 특성)

  • 이수정;김윤중;문희수
    • Journal of the Korean Ceramic Society
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    • v.38 no.2
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    • pp.199-206
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    • 2001
  • 납석-뮬라이트의 상변이 과정을 주로 에너지여과 투과전자현미경을 이용하여 연구하였다. 납석은 (OH)를 읽고 pyrophyllite dehydroxylate로 된 후 뮬라이트와 크리스토발라이트로 상변이한다. Pyrophyllite dehydroxylate의 장주기 질서는 105$0^{\circ}C$에서도 유지된다. 생성 초기단계에서 뮬라이트는 pyrophyllite dehydroxylate에 대해 topotaxy를 보이며, elongation direction이 c*인 침상 결정으로 자라기 때문에 textured ED pattern을 나타낸다. Pyrophyllite dehydroxylate는 120$0^{\circ}C$에서 완전히 분해되어 뮬라이트의 결정 성장과 비정질 실리카로부터 크리스토발라이트의 생성이 이루어진다.

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High-Resolution TEM Study on TiAs Precipitate Formation Between $TiSi_2$ and As Doped in Poly-Silicon ($TiSi_2$와 다결정 실리콘에 이온주입된 As 계에서 TiAs 침전물형성에 관한 고분해능 TEM 연구)

  • 박형호;이정용;조경익;이중환;권오준;남기수
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.28A no.5
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    • pp.375-379
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    • 1991
  • Formation of TiAs precipitate through the reaction between TiSi2 with C54 structure and heavily doped arsenic ion in poly-silicon, and influence of TiSAs and silicon distribution resulted from the reaction TiSi2+As ->2Si on the morphology degradation have been studied.

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Microstructure analyses of aluminum nitride (AlN) using transmission electron microscopy (TEM) and electron back-scattered diffraction (EBSD) (투과전자현미경과 전자후방산란회절을 이용한 AlN의 미세구조 분석)

  • Joo, Young Jun;Park, Cheong Ho;Jeong, Joo Jin;Kang, Seung Min;Ryu, Gil Yeol;Kang, Sung;Kim, Cheol Jin
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.25 no.4
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    • pp.127-134
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    • 2015
  • Aluminum nitride (AlN) single crystals have attracted much attention for a next-generation semiconductor application because of wide bandgap (6.2 eV), high thermal conductivity ($285W/m{\cdot}K$), high electrical resistivity (${\geq}10^{14}{\Omega}{\cdot}cm$), and high mechanical strength. The bulk AlN single crystals or thin film templates have been mainly grown by PVT (sublimation) method, flux method, solution growth method, and hydride vapor phase epitaxy (HVPE) method. Since AlN suffers difficulty in commercialization due to the defects that occur during single crystal growth, crystalline quality improvement via defects analyses is necessary. Etch pit density (EPD) analysis showed that the growth misorientations and the defects in the AlN surface exist. Transmission electron microscopy (TEM) and electron back-scattered diffraction (EBSD) analyses were employed to investigate the overall crystalline quality and various kinds of defects. TEM studies show that the morphology of the AlN is clearly influenced by stacking fault, dislocation, second phase, etc. In addition EBSD analysis also showed that the zinc blende polymorph of AlN exists as a growth defects resulting in dislocation initiator.

TEM Study of Micropores Developed on Pitch-based Carbon Fiber

  • Ryu, Seung-Kon;Lu, Ji Gui
    • Carbon letters
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    • v.7 no.2
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    • pp.114-118
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    • 2006
  • Isotropic pitch-based carbon fiber has been activated by steam diluted in nitrogen in order to characterize the microporosity. Especially, 40 wt% burn-off ACFs were prepared from different conditions to compare the pore structure and size. The ACFs were thinly sliced to investigate the inside pores by TEM and image analyzer. As expected, the adsorption characteristics of these ACFs were quite different from one another because of different pore structure and size. Most pores are not slit-shaped but rather round. Small round micropores become broad and irregular as increasing the activation time and temperature.

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Fourier Transformations (TEM 관련 이론해설 (2): Fourier 변환)

  • Lee, Hwack-Joo
    • Applied Microscopy
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    • v.32 no.3
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    • pp.195-204
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    • 2002
  • In this review, the fundamental concepts of delta function, convolution integral and Fourier transformation are discussed. The applications of Fourier transformation to slit function, two very narrow slits, two slits of appreciable width, periodic array of narrow slits, arbitary periodic function, diffraction gratings and gaussian functions are also introduced.

Microstructure and Third Order Optical Nonlinearities of Ion-Implanted and Thermally Annealed $Cu-SiO_2$ Thin Films

  • 채이;이민영;김현경;문대원
    • Bulletin of the Korean Chemical Society
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    • v.18 no.8
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    • pp.886-889
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    • 1997
  • The crystal structure and optical properties of copper nanoparticles, prepared in fused silica by ion-implantation and subsequent heat-treatment, were characterized by X-ray, TEM, linear absorption, and degenerate four-wave mixing (DFWM) technique. The X-ray data show fcc lattice structure of the nanocrystals and their size was measured as 8-20 nanometer by high resolution TEM. Using DFWM, the third-order nonlinear optical coefficient of the Cu-SiO2 thin films was measured as 0.4-1.1×10-8 esu in the surface plasmon resonance absorption region (540-570 nm).

Intergrowth and Interlayering of Muscovite, Chlorite, and Biotite in a Garnet Zone Metamorphic Rock of the Ogcheon Belt, South Korea (옥천대의 석류석데 변성암에서 산출되는 백운모, 녹니석 및 흑운모의 Intergrowth와 Interlayering)

  • Yeong Boo Lee;Jung Hoo Lee;Chang Whan Oh
    • Journal of the Mineralogical Society of Korea
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    • v.15 no.2
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    • pp.122-131
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    • 2002
  • Muscovite, chlorite and biotite in metapelites of the Ogcheon Hetamorphic Belt are studied using electron probe microanalysis (EPMA), backscattered electron images (BEI) of scanning electron microscopy (SEM) and lattice fringe images of transmission electron microscopy (TEM). These minerals are observed to be intergrown under a polarized light microscope and are apparently interlayered below EPMA resolution; EPMA data often indicate mixtures of phyllosilicates such as muscovite/chlorite (M/C), biotite/chlorite (B/C), muscovite/pyrophyllite/chlorite (M/P/C). biotite/pyrophyllite/chlorite (B/P/C) or biotite/muscovite/chlorite (B/M/C). BEI observations show that the three minerals (muscovite, chlorite and biotite) are mixed at various scales in a grain through the garnet zone, and the interlayering of the three minerals are observed from TEM lattice fringe images and selected area electron diffraction patterns. The result of TEM observations reveals that 7-$\AA$ layers (serpentine, precursor of chlorite) are interlayered within 10-$\AA$ layers (muscovite) at 100~200 $\AA$ scale as well as M/C in the chlorite zone. The 7-$\AA$ layers become smaller in size and less frequent in the biotite tone, and 10-$\AA$ layers are interlayered with chlorite (14 $\AA$) at an individual layer scale. The 7-$\AA$ layers are no longer observed in the garnet zone, and 10-$\AA$ layers (biotite) are interlayered with chlorite (B/C) at 50~100 $\AA$ scale. Relatively large scale (1000~2000 $\AA$) of intergrowth is also frequently observed from the garnet zone samples. However, rocks from all three metamorphic zones show interlayering of a few units of 7-, 10- and 14-$\AA$ layers with each other at TEM observations. The result of this study implies that metamorphic minerals such as muscovite, chlorite and biotite form through disequilibrum mineral reactions resulting in inhomogenious phases.