• 제목/요약/키워드: Single-crystalline

검색결과 681건 처리시간 0.028초

$Al_2O_3$성장을 위한 DC-MOTOR의 위치 제어 구현 (Implementation of Position Control DC-Motor for $Al1_2O_3$ Growth)

  • 이형충;박종국;조현섭
    • 한국산학기술학회:학술대회논문집
    • /
    • 한국산학기술학회 2004년도 춘계학술대회
    • /
    • pp.213-216
    • /
    • 2004
  • It is a quite quality concerning to control temperature of single crystalline growth as it does when you get most of heat treating products. It is also important factor to control temperature when you make the $A1_2O_3$(single crystalline) used to artificial jewels, glass of watches, heat resistant transparent glasses. Thus, it is a major interest to get the proper temperature in accordance with the time process while you are making mixture of oxygen and hydrogen to have the right temperature. In this paper, we will study of electrical valve positioning system for the gas mixture to improve the quality of products.

  • PDF

산소 플라즈마에서의 분자살 적층성장에 의한 $CeO_2$ 박막의 성장과 구조 (Growth and structure of $CeO_2$ films by oxygen-plasma-assisted molecular beam epitaxy)

  • 김용주
    • 한국진공학회지
    • /
    • 제9권1호
    • /
    • pp.16-23
    • /
    • 2000
  • The epitaxial growth of $CeO_2$ films has been investigated on three different substrates-Si(111), $SrTiO_3$(001), and MgO(001)-over wide range of growth parameters using oxygen-plasma-assisted molecular beam epitaxy. Pure-phase, single-crystalline epitaxial films of $CeO_2$ (001) have been grown only on $SrTiO_3$(001). We discuss the growth conditions in conjunction with the choice of substrates required to synthe-size this oxide, as well as the associated characterization by menas of x-ray diffraction, reflection high-energy electron diffraction, low-energy electron diffraction, and x-ray photoelectron spectroscopy and diffraction. Successful growth of single crystalline $CeO_2$ depends critically on the choice of substrate and is rather insensitive to the growth conditions studied in this investigation. $CeO_2$(001) films on $SrTiO_3$exhibit the sturcture of bulk $CeO_2$ without surface reconstructions. Ti outdiffusion is observed on the films grown temperatures above $650^{\circ}C$.

  • PDF

Enhanced upper critical fields in low energy iron-irradiated single-crystalline MgB2 thin films

  • Pham, Duong;Jung, Soon-Gil;Tran, Duc H.;Park, Tuson;Kang, Won Nam
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제21권3호
    • /
    • pp.18-21
    • /
    • 2019
  • We studied the effect of Fe ion irradiation on the upper critical field ($H_{c2}$) of 410 nm single-crystalline $MgB_2$ thin films. The irradiation energy was fixed at 140 keV when we increased the irradiation doses from $1{\times}10^{14}ion/cm^2$ to $4{\times}10^{14}ion/cm^2$. We found that $H_{c2}$ significantly increase with increasing irradiation dose, despite the low irradiation energy. The enhancement of $H_{c2}$ could be explained by the reduction of electron mean free path caused by defects induced from irradiation, leading to a decrease of coherence length (${\xi}$). We also discussed the effect of irradiation on temperature-dependent resistivity in details.

MOD 공정으로 제조된 고임계전류 YBCO 후막 (High-Ic YBCO thick film fabricated by the MOD process)

  • 신거명;송규정;문승현;유상임
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제10권1호
    • /
    • pp.6-9
    • /
    • 2008
  • We have investigated the MOD process successfully for the fabrication of the YBCO thick film on the $LaAlO_3$(001) single crystalline substrate. The cracking problem in YBCO thick film, a serious problem in the conventional TFA-MOD method, could be overcome with a careful control of precursor materials. Thus coating solution was prepared for the YBCO thick film by using fluorine-free precursor material. The precursor solutions were coated on the LAO(001) single crystalline substrate using the dip coating method, calcined at the temperature up to $500^{\circ}C$, and fired at various high temperatures for 2 h in a reduced oxygen atmosphere. Optimally processed YBCO thick film exhibited high critical current($I_c$) over 200 A/cm-width at 77K in self-field.

X-X: Single-Crystalline Si TFTs Fabricated with ${\mu}-Czochralski$ (grain-filter) process

  • Ishihara, R.;Dijk, B.D.van;Wilt, P.Ch. van der;Metselaar, J.W.;Beenakker, C.I.M.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
    • /
    • pp.159-162
    • /
    • 2002
  • This paper reviews an advanced excimer-laser crystallization technique enabling precise location-control of the individual grains. With the developed ${\mu}$-Czochralski (grain-filter) process, the large grains having a diameter of 6 ${\mu}m$ can be set precisely at predetermined positions. We will also discuss the performance of the single-crystalline Si TFTs that are formed within the location-controlled Si grains. The field-effect mobility for electrons is 430 $cm^2/Vs$ on average, which is well comparable to that of TFTs made with silicon-on-insulator wafers.

  • PDF