Poly and Nano-crystalline High Electron Mobility Thin Film Transistors on Plastic Substrates for Large Area Applications


Thin-film transistors (TFT) of poly and nano crystalline silicon have been made at temperature as low as 170°C on flexible PET (polyethylene terephthalate) substrates.The crystallization of the silicon film has been achieved using external mechanical stress assisted by a plasma hydrogenation technique. The formation of TFT is possible by means of a lateral crystallization of amorphous silicon under the channel region. High mobility TFTs with an electron mobility of 25cm2/Vs and an on/off ratio of 2000 have been obtained. Scanning electron microscopy, X-ray diffraction analysis and optical microscopy have been used to examine the crystallinity of the layer. In addition we report the deposition of high quality low-temperature silicon-oxide layers on PET substrates using an RF-plasma enhanced chemical vapor deposition unit with direct introduction of oxygen gas into the chamber and its reaction with Silane. Infrared spectroscopy was used to examine the quality of the oxide layer.

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  1. 1.

    K. Long, A. Z. Kattamis, I. C. Cheng, H. Gleskova, S. Wagner, J. C. Sturm; “Active-matrix amorphous-silicon TFT arrays at 180°C on clear plastic and glass substrate for organic light-emitting displays” IEEE Trans. Electron Devices. 53 (2006) 8.10.1109/TED.2006.878028

    Google Scholar 

  2. 2.

    J.P. Conde, P. Alpuim, V. Chu. “Thin-film transistor on PET at 100°C” Mat. Res. Soc. Symp. Proc. 715 (2002).10.1557/PROC-715-A3.1

  3. 3.

    Zhiguo. Meng, Shuyun. Zhao, Chunya. Wu, Bo. Zhang, Man. Wong, Hoi-Sing. Kwok “Polycrystalline silicon films and thin-film transistors using solution-based metal-induced crystallization” IEEE Journal of Display. 2 (2006) 3.

    Article  Google Scholar 

  4. 4.

    Wei-Chieh. Hsueh, Si-Chen. Lee “The fabrication of polysilicon thin film transistors by copper-induced lateral crystallization” IEEE Trans. Electron Devices. 5 (2003) 3.

    Google Scholar 

  5. 5.

    B. Hekmatshoar, S. Mohajerzadeh, D. Shahrjerdi, and M.D. Robertson, “Thin-film tunneling transistors on flexible plastic substrates based on stress-assisted lateral growth of polycrystalline germanium”, Applied Physics Letters, 85 (2004) 1054–1056.10.1063/1.1779946

    CAS  Article  Google Scholar 

  6. 6.

    H. Gleskova, I-Chun. Cheng, S. Wagner, J. C. Sturm. “Mechanics of thin-film transistors and solar cells on flexible substrate” Journal of Solar energy. 80 (2006) 687–693.10.1016/j.solener.2005.10.010

    CAS  Article  Google Scholar 

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Correspondence to Sara Paydavosi.

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Paydavosi, S., Tamaddon, AH., Mohajerzadeh, S. et al. Poly and Nano-crystalline High Electron Mobility Thin Film Transistors on Plastic Substrates for Large Area Applications. MRS Online Proceedings Library 1030, 707 (2007). https://doi.org/10.1557/PROC-1030-G07-07

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