Organic Thin Film Transistors with Polymer Brush Gate Dielectrics Synthesized by Atom Transfer Radical Polymerization

Low operating voltage is an important requirement that must be met for industrial adoption of organic field-effect transistors (OFETs). We report here solution fabricated polymer brush gate insulators with good uniformity, low surface roughness and high capacitance. These ultra thin polymer films, synthesized by atom transfer radical polymerization (ATRP), were used to fabricate low voltage OFETs with both evaporated pentacene and solution deposited poly(3-hexylthiophene). The semiconductor-dielectric interfaces in these systems were studied with a variety of methods including scanning force microscopy, grazing incidence X-ray diffraction and neutron reflectometry. These studies highlighted key differences between the surfaces of brush and spun cast polymethyl methacrylate (PMMA) films.

[1]  Yuan Taur,et al.  Device scaling limits of Si MOSFETs and their application dependencies , 2001, Proc. IEEE.

[2]  Zhenan Bao,et al.  Synthesis of polymer dielectric layers for organic thin film transistors via surface-initiated ring-opening metathesis polymerization. , 2004, Journal of the American Chemical Society.

[3]  Tobin J Marks,et al.  Gate dielectric chemical structure-organic field-effect transistor performance correlations for electron, hole, and ambipolar organic semiconductors. , 2006, Journal of the American Chemical Society.

[4]  Stephen M. Martin,et al.  Structural characterization of a pentacene monolayer on an amorphous SiO2 substrate with grazing incidence x-ray diffraction. , 2004, Journal of the American Chemical Society.

[5]  N. Peppas,et al.  Effect of the degree of crosslinking on penetrant transport in polystyrene , 1985 .

[6]  Romain Quidant,et al.  Pentacene thin-film transistors with polymeric gate dielectric , 2004 .

[7]  H. Sirringhaus,et al.  Observation of Field‐Effect Transistor Behavior at Self‐Organized Interfaces , 2004 .

[8]  Paul M. Solomon,et al.  Evaluations and Considerations for Self-Assembled Monolayer Field-Effect Transistors , 2003 .

[9]  Darren M. Jones,et al.  Controlled Surface‐Initiated Polymerizations in Aqueous Media , 2001 .

[10]  R. Wallace,et al.  Effect of poly (3-hexylthiophene) film thickness on organic thin film transistor properties , 2006 .

[11]  F. Boué,et al.  Reptation and interdiffusion in polystyrene networks , 2001 .

[12]  A. Karim,et al.  Interfacial segment density profiles of end-anchored polymers in a melt , 1992 .

[13]  Christos D. Dimitrakopoulos,et al.  Molecular beam deposited thin films of pentacene for organic field effect transistor applications , 1996 .

[14]  K. Matyjaszewski,et al.  ATOM TRANSFER RADICAL POLYMERIZATION AND THE SYNTHESIS OF POLYMERIC MATERIALS , 1998 .

[15]  Darren M. Jones,et al.  Surface-Initiated Polymerizations in Aqueous Media: Effect of Initiator Density , 2002 .

[16]  Ute Zschieschang,et al.  Low-voltage organic transistors with an amorphous molecular gate dielectric , 2004, Nature.

[17]  Electrical field analysis of nanoscale field effect transistors , 2003, Digest of Papers Microprocesses and Nanotechnology 2003. 2003 International Microprocesses and Nanotechnology Conference.

[18]  Alan H. Muhr,et al.  Diffusion in gels , 1982 .

[19]  Dago M. de Leeuw,et al.  Field-effect transistors made from solution-processed organic semiconductors , 1997 .

[20]  G. Baker,et al.  Functionalization of surfaces by water-accelerated atom-transfer radical polymerization of hydroxyethyl methacrylate and subsequent derivatization , 2002 .

[21]  M. Bruening,et al.  Surface-Initiated Thermal Radical Polymerization on Gold , 2001 .

[22]  D. Dyer,et al.  Patterning of Gold Substrates by Surface‐Initiated Polymerization , 2003 .

[23]  W. Huck,et al.  Polymer brushes via surface-initiated polymerizations. , 2004, Chemical Society reviews.

[24]  Tobin J Marks,et al.  Low-voltage organic field-effect transistors and inverters enabled by ultrathin cross-linked polymers as gate dielectrics. , 2005, Journal of the American Chemical Society.

[25]  R. Bruce Lennox,et al.  Insulating Properties of Self-Assembled Monolayers Monitored by Impedance Spectroscopy , 2000 .

[26]  J. Penfold,et al.  The application of the specular reflection of neutrons to the study of surfaces and interfaces , 1990 .

[27]  G. Scoles,et al.  Structure of pentacene thin films , 2004 .

[28]  W. Huck,et al.  Buckling in Quasi‐2D Polymers , 2006 .

[29]  D. Vuillaume,et al.  Octadecyltrichlorosilane monolayers as ultrathin gate insulating films in metal‐insulator‐semiconductor devices , 1993 .

[30]  H. Klauk,et al.  Ultralow-power organic complementary circuits , 2007, Nature.

[31]  Janos Veres,et al.  Gate Insulators in Organic Field-Effect Transistors , 2004 .

[32]  F. Rondelez,et al.  Evidence of a transition temperature for the optimum deposition of grafted monolayer coatings , 1992, Nature.