• 제목/요약/키워드: Polycrystalline structure

검색결과 388건 처리시간 0.035초

두 단계 열처리에 의해 제작된 다결정 실리콘 박막트랜지스터의 전기적 특성의 분석 (Analysis of electrical properties of two-step annealed polycrystalline silicon thin film transistors)

  • 최권영;한민구;김용상
    • 대한전기학회논문지
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    • 제45권4호
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    • pp.568-573
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    • 1996
  • The amorphous silicon films deposited by low pressure chemical vapor deposition are crystallized by the various annealing techniques including low-temperature furnace annealing and two-step annealing. Two-step annealing is the combination of furnace annealing at 600 [.deg. C] for 24 h and the sequential furnace annealing at 950 [.deg. C] 1h or the excimer laser annealing. It s found that two-step annealings reduce the in-grain defects significantly without changing the grain boundary structure. The performance of the poly-Si thin film transistors (TFTs) produced by employing the tow-step annealing has been improved significantly compared with those of one-step annealing. (author). 13 refs., 6 figs., 1 tab.

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채널에 단일 그레인 경계를 갖는 다결정 실리콘박막 트랜지스터 (An Excimer Laser Annealed Poly-Si Thin Film Transistor Designed for Reduction of Grainboundary Effect)

  • 전재홍
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제52권12호
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    • pp.559-561
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    • 2003
  • We report a new excimer laser annealing method which successfully results in a single grain boundary formation in the channel of polycrystalline silicon thin film transistor. The proposed method is based on lateral grain growth and employs aluminum patterns which act as selective beam mask and lateral heat sink. The maximum grain size obtained by the proposed method is about 1.6${\mu}{\textrm}{m}$ in the length. The grainboundaries should be arranged parallel with the direction of current flow for the best device performance, so we propose a new device fabrication method and a new poly-Si TFT structure. Poly-Si TFT fabricated by the proposed method exhibits considerably improved electrical characteristics, such as high field effect mobility exceeding 240 $cm^2$/Vsec.

Amorphous-$Si_xGe_y$을 seed layer로 이용한 Poly-Si TFT의 특성 (Characterization of Poly-Si TFT's using Amorphous-$Si_xGe_y$ for Seed Layer)

  • 정명호;정종완;조원주
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.125-126
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    • 2007
  • Polycrystalline silicon thin-film-transistors (Poly-Si TFT's) with a amorphous-$Si_xGe_y$ seed layer have been fabricated to improve the performance of TFT. The dependence of crystal structure and electrical characteristics on the the Ge fractions in $Si_xGe_y$ seed layer were investigated. As a result, the increase of grain size and enhancement of electrical characteristics were obtained from the poly-Si TFT's with amorphous-SixGey seed layer.

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RF 스퍼터링법에 의한 SBT박막의 분극특성 (Polarization Properties of SBT Thin Film by RF Sputtering)

  • 김태원;조춘남;김진사;유영각;김충혁;박용필;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.893-896
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    • 2000
  • The SrBi$_2$Ta$_2$O$\sub$9/(SBT) thin films are deposited on Pt-coated electrode(Pt/TiO$_2$/SiO$_2$/Si) using RF sputtering method. The SBT thin films deposited on substrate at 400-500[$^{\circ}C$]. SBT thin film deposited on Pt-coated electrodes have the cubic perovskite structure and polycrystalline state. With increasing annealing temperature from 600[$^{\circ}C$] to 850[$^{\circ}C$], flourite Phase was crystalized to 650[$^{\circ}C$] and Bi-layered perovskite phase was crystalized above 700[$^{\circ}C$]. The maximum remanent polarization is 11.73 ${\mu}$C/cm$^2$at 500[$^{\circ}C$] of substrate temperature and 750[$^{\circ}C$] annealing temperature for 30min.

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열처리 온도에 따른 SCT 박막의 미세구조 및 유전특성 (Microstructure and Dielectric Properties of SCT Thin Film with Annealing Temperature)

  • 김진사;조춘남;신철기;박건호;최운식;이성일;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.244-247
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    • 1999
  • The(Sr$\sub$0.85/Ca$\sub$0.15/) TiO$_3$(SCT) thin films are deposited on Pt-coated electrode(Pt/TiN/SiO$_2$/Si) using RF sputtering method. The composition of SCT thin films deposited on Si substrate at room temperature is close to stoichiometry(1.102 in A/B ratio). Also, SCT thin films deposited on Pt-coated electrodes have the cubic perovskite structure and polycrystalline state. The maximum dielectric constant of SCT thin films is obtained by annealing at 600[$^{\circ}C$].The dielectric constant changes almost linearly in temperature ranges of -80~+90[$^{\circ}C$].

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고분자 기판 상에 제작된 극저온 다결정 실리콘 박막 트랜지스터에 관한 연구 (Fabrication of Ultra Low Temperature Poly crystalline Silicon Thin-Film Transistors on a Plastic Substrate)

  • 김영훈;김원근;문대규;한정인
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.445-446
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    • 2005
  • This letter reports the fabrication of polycrystalline silicon thin-film transistors (poly-Si TFT) on flexible plastic substrates using amorphous silicon (a-Si) precursor films by sputter deposition. The a-Si films were deposited with mixture gas of argon and helium to minimize the argon incorporation into the film. The precursor films were then laser crystallized using XeCl excimer laser irradiation and a four-mask-processed poly-Si TFTs were fabricated with fully self-aligned top gate structure.

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분위기 소결한 PZT 후막의 구조적 특성 (Structural Properties of PZT Thick Films Fabricated by the Atmospheric Sintering)

  • 이성갑;심영재;이영희;배선기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.313-314
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    • 2005
  • $PbTiO_3$ and PZT(52/48) powders, prepared by the sol-gel method, were mixed with an organic vehicle and the PT/PZT(52/40) heterolayered thick films were fabricated by the screen-printing method on Pt/$Al_2O_3$ substrates. The structural properties such as DTA, X-ray diffraction and microstructure, were examined as a amount of the PbO-$PbF_2$ flux. In the X-ray diffraction analysis, PZT(52/48) thick films showed a perovskite polycrystalline structure without a pyrochlore phase.

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엑시머 레이저를 이용한 저온 다결정 실리콘 박막 트랜지스터의 특성 (Characteristics of low temperature poly-Si thin film transistor using excimer laser annealing)

  • 강수희;김영훈;한진우;서대식;한정인
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.430-431
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    • 2006
  • This letter reports the fabrication of polycrystalline silicon thin-film transistors (poly-Si TFT) on flexible plastic substrates using amorphous silicon (a-Si) precursor films by sputter deposition. The a-Si films were deposited with mixture gas of argon and helium to minimize the argon incorporation into the film. The precursor films were then laser crystallized using XeCl excimer laser irradiation and a four-mask-processed poly-Si TFTs were fabricated with fully self-aligned top gate structure.

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Substrate Temperature Effects on Structural and Optical Properties of RF Sputtered CdS Thin Films

  • 황동현;최정규;손영국
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.218.2-218.2
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    • 2013
  • In this study, CdS thin films were deposited onto glass substrates by radio frequency magnetron sputtering. The films were grown at various substrate temperatures in the range of 100 to $250^{\circ}C$. The effects of substrate temperatures on the structural and optical properties were examined. The XRD analysis revealed that CdS films were polycrystalline and retained the mixed structure of hexagonal wurtzite and cubic phase. The percentages of hexagonal structured crystallites in the films were seen to be increased by increasing substrate temperatures. The film grown at $250^{\circ}C$ showed a relatively high transmittance of 80% in the visible region, with an energy band gap of 2.45 eV. The transmittance date analysis indicated that the optical band gap was closely related to the substrate temperatures.

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$300^{\circ}C$$500^{\circ}C$사이에서 산회된 304, 316 스테인리스강의 표면특성 (A Surface Study of 304 and 316 Stainless Steel Oxidized between $300^{\circ}C$ and $500^{\circ}C$)

  • 김경록;이경구;강창석;최답천;이도재
    • 한국표면공학회지
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    • 제32권1호
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    • pp.43-48
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    • 1999
  • Oxidation behavior of 304 and 316 stainless steels was studied. After solution heat treatment, specimens were polished up to 1$mu \textrm{m}$ using $Al_2O_3$ powder and then subjected to oxidation between $300^{\circ}C$ and 50$0^{\circ}C$ in dry air. TEM and EDS were used for analyzing the components and structure of oxide film. TEM analysis of oxide film revealed that thin amorphous Fe oxide ($Fe_2O_3$) was formed on the top of surface while polycrystalline (Cr, $Fe_2O_3$ was formed below the amorphous Fe oxide layer. The specimens oxidized at $500^{\circ}C$ showed that 316 stainless steel had higher oxidation resistance than 304 stainless steel. These results suggest that Mo component of 316 stainless steel suppresses the formation of Cr carbide which may result in a local Cr depleted area.

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