Percolation behaviour in high mobility p-channel polymer/small-molecule blend organic field-effect transistors

Jeremy Smith, Martin Heeney, Iain McCulloch, Jennifer Nekuda Malik, Natalie Stingelin, Donal D.C. Bradley, Thomas D. Anthopoulos

Research output: Contribution to journalArticlepeer-review

44 Scopus citations


Organic transistors based on blends of 2,8-difluoro-5,11- bis(triethylsilylethynyl) anthradithiophene (diF-TES ADT) and poly(triarylamine) [PTAA] are strong candidates for application in future large-volume organic electronics because of their record breaking carrier mobility and environmental stability. Here we report on the dependence of hole transport on the composition of diF-TES ADT:PTAA blends. Maximum mobility is obtained only for blends containing ≥39 wt.% diF-TES ADT. At compositions below this threshold the hole mobility is drastically reduced and is found to be equal to that of the neat polymer matrix, i.e. PTAA (∼10-3 cm2/V s). Scanning atomic force and polarised light microscopy, combined with differential scanning calorimetry, show that this threshold corresponds to the appearance of crystalline, acene-rich regions in such blend films, and the formation of high mobility conduction pathways between the source and drain electrodes. The dependence of hole mobility on diF-TES ADT concentration can be modelled using a simple percolation model. The present results provide important insights into the microstructure evolution in this high performance semiconducting blend and could prove valuable for the development of the next generation organic transistors.

Original languageEnglish (US)
Pages (from-to)143-147
Number of pages5
JournalOrganic Electronics
Issue number1
StatePublished - Jan 2011
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • General Chemistry
  • Biomaterials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering
  • Materials Chemistry


  • Blend organic semiconductors
  • Electronic percolation
  • Organic field-effect transistors


Dive into the research topics of 'Percolation behaviour in high mobility p-channel polymer/small-molecule blend organic field-effect transistors'. Together they form a unique fingerprint.

Cite this