Experimental and numerical analysis of channel-length-dependent electrical properties in bottom-gate, bottom-contact organic thin-film transistors with Schottky contact

Kei Noda, Yasuo Wada, Toru Toyabe

Research output: Contribution to journalArticle

8 Citations (Scopus)


Channel length dependence of field-effect mobility and source/drain parasitic resistance in pentacene thin-film transistors with a bottom-gate, bottom-contact configuration was investigated. Schottky barrier effect such as nonlinear behaviors in transistor output characteristics appeared and became more prominent for shorter channel length less than 10 μm, raising some concerns for a simple utilization of conventional parameter extraction methods. Therefore the gate-voltage-dependent hole mobility and the source/drain parasitic resistance in the pentacene transistors were evaluated with the aid of device simulation accounting for Schottky contact with a thermionic field emission model. The hole mobility in the channel region shows smaller values with shorter channel length even after removing the influence of Schottky barrier, suggesting that some disordered semiconductor layers with low carrier mobility exist near the contact electrode. This experimental data analysis with the simulation enables us to discuss and understand in detail the operation mechanism of bottom-gate, bottom-contact transistors by considering properly each process of charge carrier injection, carrier flow near the contact region, and actual channel transport.

Original languageEnglish
Pages (from-to)3681-3687
Number of pages7
JournalOrganic Electronics
Issue number12
Publication statusPublished - 2014 Dec



  • Bottom-gate, bottom-contact configuration
  • Device simulation
  • Organic thin-film transistors
  • Schottky barrier
  • Thermionic field emission

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Chemistry(all)
  • Condensed Matter Physics
  • Materials Chemistry
  • Electrical and Electronic Engineering

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