Control of carrier density by self-assembled monolayers in organic field-effect transistors

Nat Mater. 2004 May;3(5):317-22. doi: 10.1038/nmat1105. Epub 2004 Apr 4.


Organic thin-film transistors are attracting a great deal of attention due to the relatively high field-effect mobility in several organic materials. In these organic semiconductors, however, researchers have not established a reliable method of doping at a very low density level, although this has been crucial for the technological development of inorganic semiconductors. In the field-effect device structures, the conduction channel exists at the interface between organic thin films and SiO(2) gate insulators. Here, we discuss a new technique that enables us to control the charge density in the channel by using organosilane self-assembled monolayers (SAMs) on SiO(2) gate insulators. SAMs with fluorine and amino groups have been shown to accumulate holes and electrons, respectively, in the transistor channel: these properties are understood in terms of the effects of electric dipoles of the SAMs molecules, and weak charge transfer between organic films and SAMs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Computer Simulation
  • Crystallization / methods*
  • Electric Conductivity
  • Electron Transport
  • Equipment Design
  • Equipment Failure Analysis
  • Models, Molecular*
  • Molecular Conformation
  • Nanotechnology / instrumentation*
  • Nanotechnology / methods*
  • Organic Chemicals / chemistry*
  • Silanes / chemistry*
  • Silicon Dioxide / chemistry*
  • Transistors, Electronic*


  • Organic Chemicals
  • Silanes
  • Silicon Dioxide