Organic field-effect transistors with molecularly doped polymer gate buffer layer

Yuji Yamagishi, Kei Noda, Hirofumi Yamada, Kazumi Matsushige

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Organic field-effect transistors (OFETs) with molecularly doped poly(methylmethacrylate) (PMMA) gate buffer layer were newly investigated. Acceptor doped PMMA buffer layers with a thickness of 8 nm were deposited onto SiO 2 gate insulator by spin-coating methylethylketone solution containing both PMMA and molecular dopants such as tetrafluorotetracyanoquinodimethane (F4TCNQ). Gate threshold voltage shifts in positive direction were commonly observed for both p-channel and n-channel transistors with F4TCNQ doped PMMA gate buffer layer. In p-channel pentacene thin-film transistors, higher dopant ratio led to the increase in the effective hole mobility due to hole doping caused by charge transfer between pentacene and F4TCNQ molecules. In n-channel transistors based on 1,4,5,8- naphthalenetetracarboxylicdianhydride (NTCDA) and copper hexadecafluorophthalocyanine (F16CuPc), F4TCNQ molecules doped into the PMMA layer behave as electron traps and NTCDA transistors are more susceptible to acceptor dopants than F16CuPc ones. This phenomenon in the n-channel transistors can be explained by energetic differences between unoccupied molecular orbital (LUMO) levels of host organic semiconductor and dopant molecules.

Original languageEnglish
Pages (from-to)1887-1893
Number of pages7
JournalSynthetic Metals
Volume162
Issue number21-22
DOIs
Publication statusPublished - 2012 Dec 1
Externally publishedYes

    Fingerprint

Keywords

  • Electron trap
  • Hole doping
  • Molecularly doped gate buffer layer
  • Organic field-effect transistor
  • Threshold voltage shift

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

Cite this