Science China Information Sciences

, Volume 58, Issue 4, pp 1–6 | Cite as

Self-aligned offset gate poly-Si TFTs using photoresist trimming technology

  • LongYan Wang
  • Lei Sun
  • DeDong Han
  • Yi Wang
  • ManSun Chan
  • ShengDong ZhangEmail author
Research Paper


This paper reports a simple method of fabricating self-aligned offset gate (SAOG) polycrystalline silicon (poly-Si) thin film transistors (TFTs). The SAOG structure was formed by two key steps, i.e. an isotropic photoresist trimming and an additional gate fringe etching. The fabricated SAOG devices with this proposed method exhibit a significantly suppressed off-current increase with gate bias compared with the non-offset ones, and have identical bi-directional transfer characteristics under reversed source/drain biases. It is also shown that the performances of poly-Si TFTs with metal-induced lateral crystallization can be improved significantly by annealing in forming gas.


photoresist trimming offset polycrystalline silicon (poly-Si) thin film transistors (TFTs) 


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Copyright information

© Science China Press and Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • LongYan Wang
    • 1
    • 2
  • Lei Sun
    • 1
  • DeDong Han
    • 1
  • Yi Wang
    • 1
  • ManSun Chan
    • 3
  • ShengDong Zhang
    • 1
    • 4
    Email author
  1. 1.Institute of MicroelectronicsPeking UniversityBeijingChina
  2. 2.BOE Technology Co. Ltd.BeijingChina
  3. 3.Department of Electronic and Computer EngineeringHong Kong University of Science and TechnologyHong KongChina
  4. 4.School of Electronic and Computer EngineeringPeking UniversityShenzhenChina

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