• Title/Summary/Keyword: Annealing of amorphous

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Application of rapid thermal annealing process to the aluminum induced crystallization of amorphous silicon thin film (비정질 실리콘의 부분적 알루미늄 유도 결정화 공정에서의 급속 열처리 적용 가능성)

  • Hwang, Ji-Hyun;Yang, Su-Won;Kim, Young-Kwan
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.29 no.2
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    • pp.50-53
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    • 2019
  • In this study, polycrystalline silicon thin film useful for the solar cells was fabricated by AIC(Aluminum Induced Crystallization) process. A diffusing barrier for this process is prepared with $Al_2O_3$. For the maximization of the grain size of the polycrystalline silicon, a selective blasting of the $Al_2O_3$ diffusing barrier was conducted before annealing treatment. The heat treatment for the activation of the amorphous-Si (a-Si) layer was carried out with Rapid Thermal Annealing (RTA) process. Crystallization of the a-Si layer was analyzed with XRD. It was confirmed that a-Si was crystallized at $500^{\circ}C$ and the silicon crystal is observed to be formed and the grain size of the polycrystalline silicon was observed to be $15.9{\mu}m$.

The Influence of the Annealing of Corn Starch on the formation and Characteristics of Enzyme-resistant Starch

  • Yoon, Ji-Young;Lee, Young-Eun
    • Preventive Nutrition and Food Science
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    • v.4 no.4
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    • pp.215-220
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    • 1999
  • The Physical properties of corn starch were investigated by scanning electron microscopy, X-ray diffractometry and differential scanning calorimetry during the formation of enzyme-resistant starch(RS). Samples were studied in their native states and after annealing at 50, 55, 60 and 65℃ in excess water(starch : water=1:3) for 48hr. Starch granules became smaller and more rounded after annealing than in their native state. Annealing did not change the X-ray profile of native corn starch. After autoclaving-cooling cycles, native starch lost most of its crystallinity but annealed ones showed some of their crystallinity left as diffuse or poor B-type, which didn't relate to increasing Rs yields. During formation of RS, however, both native and annealed starches changed their X-ray profile from A-type to poor B-type of retrograded amylose. Annealing caused an increase in gelatinization temperature and enthalpy, but a narrowing of gelatinization temperature range. Only starch annealed at 65℃, however, showed a decrease in enthalpy even though its gelatinization temperature increased, which appeared to be due to the partial gelatinization in the amorphous region during annealing. Peak height index(PHI), the ratio of ΔH to Ti-To, increased by annealing. PHI values, therefore, showed the possibility as an indicator to predict RS yield which cannot be differentiated by differential scanning calorimetry and X-ray diffraction data.

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Study on Electrical Properties and Structures of SnO2 Thin Films Depending on the Annealing Temperature (SnO2 박막의 열처리온도에 따른 결정성과 전기적인 특성 연구)

  • Yeon, Su Ji;Lee, Sung Hee;Oh, Teresa
    • Industry Promotion Research
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    • v.1 no.2
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    • pp.7-11
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    • 2016
  • $SnO_2$ films were annealed in a vacuum atmosphere conditions to research the temperature dependency of current-voltage characteristics, crystal structure and chemical properties. The $SnO_2$ film annealed in a vacuum became an amorphous structure, but the degree of amorphous structure changed in accordance with the content of oxygen vacancy, which increased at film annealed at $100^{\circ}C$ and then decreased over the sample at annealed at $150^{\circ}C$. Because the crystallinity was affected the content of oxygen vacancy. The oxygen vacancy as carriers disappeared with increasing the annealing temperatures, and the depletion layer increased. Therefore the content of exiton as optical properties increased with becoming the amorphous structure. So the intensity of PL spectra increased with increasing the annealing temperature.

The physical properties and switching characteristics of amorphous $Ge_2Sb_2Te_5$ thin film (비정질 $Ge_2Sb_2Te_5$ 박막의 물리적 성질 및 스위칭 특성)

  • Lee, Jae-Min;Yang, Sung-Jun;Shin, Kyung;Chung, Hong-Bay
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.268-271
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    • 2004
  • The phase transition from amorphous to crystalline states, and vice versa, of $Ge_2Sb_2Te_5$ films by applying electrical pulses have been studied. This material can be used as nonvolatile memory. The reversible phase transition between the amorphous and crystalline states, which is accompanied by a considerable change in electrical resistivity, is exploited as means to store bits of information. The nonvolatile memory cells are composed of a simple sandwich (metal/chalcogenide/metal). It was formed that the threshold voltage depends on thickness, electrode distance, annealing time and temperature, respectively.

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