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Thermal change of organic light-emitting ALQ3 thin films

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Abstract

A series of Alq3 thin films with the thicknesses of 50, 100, and 200 nm was deposited on Si substrates at room temperature using the thermal evaporation method. The thermal crystallization process of Alq3 thin films, especially 50 nm thick films, was successfully examined using high-temperature X-ray diffraction (HT-XRD) with the in-plane scan mode. Film thickness, density, and changes in surface roughness while heating were determined using X-ray reflectometry (XRR). The decreased density and increased surface roughness, which were accompanied by sublimation, indicate the instability of the Alq3 film. Thus, thermal instability is a major factor for device failure.

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Acknowledgements

The authors thank the Ministry of Education, Culture, Sports, Science and Technology (MEXT) for financial support for our High-Tech Research Center Project entitled Development of Flexible Transparent Light Emitting Display Devices.

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Authors and Affiliations

  1. Center for Hyper Media Research, Tokyo Polytechnic University, 1583 Iiyama, Atsugi, Kanagawa, 243-0297, Japan

    Mei-Han Wang, Masahiro Yahata, Yutaka Sawada, Takayuki Uchida, Hao Lei & Yoichi Hoshi

  2. Rigaku Corporation, 3-9-12 Matsubara, Akishima, Tokyo, 196-8666, Japan

    Takayuki Konya & Akira Kishi

  3. Materials and Thermochemistry Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, 116023, China

    Li-Xian Sun

  4. Department of Industrial Chemistry, Graduate School of Engineering, Tokyo Polytechnic University, 1583 Iiyama, Atsugi, Kanagawa, 243-0297, Japan

    Yutaka Sawada

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  1. Mei-Han Wang
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  2. Takayuki Konya
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  3. Masahiro Yahata
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  6. Takayuki Uchida
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  7. Hao Lei
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  8. Yoichi Hoshi
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Correspondence to Yutaka Sawada.

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Wang, MH., Konya, T., Yahata, M. et al. Thermal change of organic light-emitting ALQ3 thin films. J Therm Anal Calorim 99, 117–122 (2010). https://doi.org/10.1007/s10973-009-0486-5

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  • DOI: https://doi.org/10.1007/s10973-009-0486-5

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