Microstructural Characterization and Charge Transport in Thin Films of Conjugated Polymers

The performance of semiconducting polymers has been steadily increasing in the last 20 years. Improved control over the microstructure of these materials and a deeper understanding of how the microstructure affects charge transport are partially responsible for such trend. The development and widespread use of techniques that allow to characterize the microstructure of semiconducting polymers is therefore instrumental for the advance of these materials. This article is a review of the characterization techniques that provide information used to enhance the understanding of structure/property relationships in semiconducting polymers. In particular, the applications of optical and X-ray spectroscopy, X-ray diffraction, and scanning probe techniques in this context are described.

[1]  A. Heeger,et al.  Diffraction Line-Shape Analysis of Poly(3-dodecylthiophene): A Study of Layer Disorder through the Liquid Crystalline Polymer Transition , 1999 .

[2]  Vivek Subramanian,et al.  Solution-Processable α,ω-Distyryl Oligothiophene Semiconductors with Enhanced Environmental Stability , 2009 .

[3]  F. Spano,et al.  Absorption and spontaneous emission in aggregates of conjugated polymers , 1998 .

[4]  E. Tadmor,et al.  Grain Orientation Mapping of Polycrystalline Organic Semiconductor Films by Transverse Shear Microscopy , 2008 .

[5]  Monroe,et al.  Hopping exponential band tails. , 1985, Physical review letters.

[6]  D. Fichou,et al.  Direct Observation of Alkyl Chain Interdigitation in Conjugated Polyquarterthiophene Self‐Organized on Graphite Surfaces , 2008 .

[7]  B. Doyle,et al.  Growth of pentacene on Ag(1 1 1) surface: A NEXAFS study , 2007 .

[8]  H. Bässler,et al.  Concentration dependence of carrier mobility and diffusivity in diluted hopping systems , 1995 .

[9]  R. Street,et al.  Transport in polycrystalline polymer thin-film transistors , 2005 .

[10]  M. Chabinyc,et al.  Gap states in organic semiconductors: Hydrogen- and oxygen-induced states in pentacene , 2003 .

[11]  K. Müllen,et al.  The Influence of Morphology on High‐Performance Polymer Field‐Effect Transistors , 2009 .

[12]  V. Podzorov,et al.  Organic single-crystal field-effect transistors , 2004 .

[13]  M. Casu,et al.  Nucleation in Organic Thin Film Growth: Perylene on Al2O3/Ni3Al(111) , 2009 .

[14]  R. Coehoorn,et al.  Charge-carrier concentration dependence of the hopping mobility in organic materials with Gaussian disorder , 2005 .

[15]  H. Sirringhaus,et al.  Effect of interchain interactions on the absorption and emission of poly(3-hexylthiophene) , 2003 .

[16]  O. Rubel,et al.  On the concentration and field dependences of the hopping mobility in disordered organic solids , 2006 .

[17]  Gilles Horowitz,et al.  Temperature and gate voltage dependence of hole mobility in polycrystalline oligothiophene thin film transistors , 2000 .

[18]  Jean M. J. Fréchet,et al.  Controlling the Field‐Effect Mobility of Regioregular Polythiophene by Changing the Molecular Weight , 2003 .

[19]  M. Toney,et al.  Correlating the microstructure of thin films of poly[5,5-bis(3-dodecyl-2-thienyl)-2,2-bithiophene] with charge transport : Effect of dielectric surface energy and thermal annealing , 2008 .

[20]  S. Yeates,et al.  Organic field effect transistors from ambient solution processed low molar mass semiconductor–insulator blends , 2008 .

[21]  S. Purushothaman,et al.  Liquid Crystal Alignment on Carbonaceous Surfaces with Orientational Order , 2001, Science.

[22]  H. Sirringhaus,et al.  Noncontact potentiometry of polymer field-effect transistors , 2002 .

[23]  Shashidhar,et al.  X-ray diffuse scattering study of static undulations in multilayer films of a liquid-crystalline polymer. , 1993, Physical review letters.

[24]  W. R. Salaneck,et al.  Thermochromism in poly(3‐hexylthiophene) in the solid state: A spectroscopic study of temperature‐dependent conformational defects , 1988 .

[25]  Milos Nesladek,et al.  Fourier-Transform Photocurrent Spectroscopy for a fast and highly sensitive spectral characterization of organic and hybrid solar cells , 2008 .

[26]  R. Friend,et al.  Photoluminescence of poly(p-phenylenevinylene)–silica nanocomposites: Evidence for dual emission by Franck–Condon analysis , 2001 .

[27]  Zhenan Bao,et al.  Soluble and processable regioregular poly(3‐hexylthiophene) for thin film field‐effect transistor applications with high mobility , 1996 .

[28]  C. McNeill,et al.  X-Ray Microscopy of Photovoltaic Polyfluorene Blends: Relating Nanomorphology to Device Performance , 2007 .

[29]  H. Bässler,et al.  Charge Carrier Transport in Disordered Organic Materials in the Presence of Traps , 2005 .

[30]  J. Brédas,et al.  Shallow trap states in pentacene thin films from molecular sliding , 2005 .

[31]  G. Leising,et al.  Charge-carrier transport in disordered organic solids , 2000 .

[32]  M. Toney,et al.  Grazing incidence x-ray scattering studies of thin films of an aromatic polyimide , 1993 .

[33]  Guangming Wang,et al.  Increased mobility from regioregular poly(3-hexylthiophene) field-effect transistors , 2003 .

[34]  Milan Vanecek,et al.  Fourier-transform photocurrent spectroscopy of microcrystalline silicon for solar cells , 2002 .

[35]  Richard H. Friend,et al.  Formation of the accumulation layer in polymer field-effect transistors , 2003 .

[36]  William R. Silveira,et al.  Microscopic view of charge injection in an organic semiconductor. , 2004, Physical review letters.

[37]  H. Sirringhaus,et al.  Effects of packing structure on the optoelectronic and charge transport properties in poly(9,9-di-n-octylfluorene-alt-benzothiadiazole). , 2005, Journal of the American Chemical Society.

[38]  A. Facchetti,et al.  A high-mobility electron-transporting polymer for printed transistors , 2009, Nature.

[39]  A. Kanjilal,et al.  Interaction strength and molecular orientation of a single layer of pentacene in organic-metal interface and organic-organic heterostructures , 2008 .

[40]  M. Torkkeli,et al.  Towards General Guidelines for Aligned, Nanoscale Assemblies of Hairy‐Rod Polyfluorene , 2006 .

[41]  Bo Li,et al.  Nanostructure dependence of field-effect mobility in regioregular poly(3-hexylthiophene) thin film field effect transistors. , 2006, Journal of the American Chemical Society.

[42]  M. Torkkeli,et al.  X-ray Diffraction Studies of Multiple Orientation in Poly(9,9-bis(2-ethylhexyl)fluorene-2,7-diyl) Thin Films , 2003 .

[43]  R. Friend,et al.  Conformational defects in Durham polyacetylene: photo-induced IR absorption , 1987 .

[44]  M. Cölle,et al.  Scanning Kelvin probe microscopy on organic field-effect transistors during gate bias stress , 2007 .

[45]  K. Haenen,et al.  Absorption phenomena in organic thin films for solar cell applications investigated by photothermal deflection spectroscopy , 2005 .

[46]  R. Street,et al.  Effects of molecular oxygen and ozone on polythiophene-based thin-film transistors , 2007 .

[47]  Martijn Kemerink,et al.  Real versus measured surface potentials in scanning Kelvin probe microscopy. , 2008, ACS nano.

[48]  F. Himpsel,et al.  Polarized optical absorption spectroscopy, NEXAFS, and GIXRD measurements of chain alignment in polyfluorene thin films , 2008 .

[49]  Lin-Wang Wang,et al.  Electronic structure of disordered conjugated polymers: polythiophenes. , 2008, The journal of physical chemistry. B.

[50]  Henning Sirringhaus,et al.  Enhanced Mobility of Poly(3-hexylthiophene) Transistors by Spin-Coating from High-Boiling-Point Solvents , 2004 .

[51]  D. Kumaki,et al.  Surface-energy-dependent field-effect mobilities up to 1 cm2/V s for polymer thin-film transistor , 2009 .

[52]  M. Salmeron,et al.  Scratching the Surface: Fundamental Investigations of Tribology with Atomic Force Microscopy. , 1997, Chemical reviews.

[53]  R. J. Kline,et al.  X-ray scattering study of thin films of poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene). , 2007, Journal of the American Chemical Society.

[54]  Harald Ade,et al.  Near-edge X-ray absorption fine-structure microscopy of organic and magnetic materials. , 2009, Nature materials.

[55]  Jean-Luc Brédas,et al.  Charge transport in organic semiconductors. , 2007, Chemical reviews.

[56]  Wen-li Wu,et al.  Polymer chain relaxation: Surface outpaces bulk , 2001 .

[57]  Ping Liu,et al.  Unique Polymorphism of Oligothiophenes , 2007 .

[58]  N. Tessler,et al.  Charge transport in conjugated polymers -- The influence of charge concentration , 2003 .

[59]  Bradley,et al.  Optical spectroscopy of field-induced charge in poly(3-hexyl thienylene) metal-insulator-semiconductor structures: Evidence for polarons. , 1991, Physical review letters.

[60]  Wi Hyoung Lee,et al.  Versatile Use of Vertical‐Phase‐Separation‐Induced Bilayer Structures in Organic Thin‐Film Transistors , 2008 .

[61]  A. Heeger,et al.  X-ray structural studies of poly(3-alkylthiophenes): an example of an inverse comb , 1992 .

[62]  Ullrich Scherf,et al.  Organic semiconductors for solution-processable field-effect transistors (OFETs). , 2008, Angewandte Chemie.

[63]  D. Jiang,et al.  Structure of tetracene films on hydrogen-passivated Si(001) studied via STM, AFM and NEXAFS , 2006 .

[64]  H. Ringsdorf,et al.  Structure and Defects in Sanidic Liquid Crystalline Polymers. 1 , 1995 .

[65]  Martin Heeney,et al.  Undoped polythiophene field-effect transistors with mobility of 1cm2V−1s−1 , 2007 .

[66]  Effective-medium theory of hopping charge-carrier transport in weakly disordered organic solids , 2002 .

[67]  R. D. Mccullough,et al.  Evidence of a Novel Side Chain Structure in Regioregular Poly(3-alkylthiophenes) , 1996 .

[68]  H. Chan,et al.  Solvent effects and multiple aggregate states in high-mobility organic field-effect transistors based on poly(bithiophene-alt-thienothiophene) , 2008 .

[69]  J. Marohn,et al.  Microscopic Evidence for Spatially Inhomogeneous Charge Trapping in Pentacene , 2005, Advanced materials.

[70]  S. Mannsfeld,et al.  Thin film structure of tetraceno[2,3-b]thiophene characterized by grazing incidence X-ray scattering and near-edge X-ray absorption fine structure analysis. , 2008, Journal of the American Chemical Society.

[71]  A. Salleo,et al.  Connecting Electrical and Molecular Properties of Semiconducting Polymers for Thin-Film Transistors , 2008 .

[72]  Youngsuk Jung,et al.  Influence of Dielectric Surface Chemistry on the Microstructure and Carrier Mobility of an n‐Type Organic Semiconductor , 2009 .

[73]  Alexander Hexemer,et al.  Interfacial widths of conjugated polymer bilayers. , 2009, Journal of the American Chemical Society.

[74]  T. Russell,et al.  X-ray and neutron reflectivity for the investigation of polymers , 1990 .

[75]  Jean M. J. Fréchet,et al.  Dependence of Regioregular Poly(3-hexylthiophene) Film Morphology and Field-Effect Mobility on Molecular Weight , 2005 .

[76]  Brandon M. Vogel,et al.  Variations in semiconducting polymer microstructure and hole mobility with spin-coating speed , 2005 .

[77]  Henning Sirringhaus,et al.  Device Physics of Solution‐Processed Organic Field‐Effect Transistors , 2005 .

[78]  G. Wegner,et al.  Effect of Molecular Weight on the Structure and Crystallinity of Poly(3-hexylthiophene) , 2006 .

[79]  M. Winokur,et al.  Structure and Morphology of Polyfluorenes in Solutions and the Solid State , 2008 .

[80]  A. Troisi,et al.  A realistic description of the charge carrier wave function in microcrystalline polymer semiconductors. , 2009, Journal of the American Chemical Society.

[81]  Gwyn P. Williams,et al.  Chemisorption geometry of poly-3-methylthiophene electrochemically deposited on Pt as observed by NEXAFS , 1987 .

[82]  Soeren Steudel,et al.  Influence of the dielectric roughness on the performance of pentacene transistors , 2004 .

[83]  D. Ginger,et al.  Electrical Scanning Probe Microscopy on Active Organic Electronic Devices , 2009 .

[84]  Richard L. Martin,et al.  Electronic structure of self-assembled amorphous polyfluorenes. , 2008, ACS nano.

[85]  R. Coehoorn.  Hopping mobility of charge carriers in disordered organic host-guest systems: Dependence on the charge-carrier concentration , 2007 .

[86]  N. Koch,et al.  Grain‐Boundary Evolution in a Pentacene Monolayer , 2008 .

[87]  F. Spano.  Absorption in regio-regular poly(3-hexyl)thiophene thin films: Fermi resonances, interband coupling and disorder , 2006 .

[88]  A. Salleo.  Charge transport in polymeric transistors , 2007 .

[89]  Brandon M. Vogel,et al.  Measuring molecular order in poly(3-alkylthiophene) thin films with polarizing spectroscopies. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[90]  R. J. Kline,et al.  High Carrier Mobility Polythiophene Thin Films: Structure Determination by Experiment and Theory† , 2007 .

[91]  Gregory L. Whiting,et al.  Organic Thin Film Transistors with Polymer Brush Gate Dielectrics Synthesized by Atom Transfer Radical Polymerization , 2008 .

[92]  H. Bässler,et al.  Theory of low‐field hopping mobility in organic solids with energetic and positional disorder , 2006 .

[93]  E. W. Meijer,et al.  Two-dimensional charge transport in self-organized, high-mobility conjugated polymers , 1999, Nature.

[94]  H. Ade,et al.  Resonant soft x-ray reflectivity of organic thin films , 2007 .

[95]  Richard A. L. Jones,et al.  A neutron reflectometry study of the interface between poly(9,9-dioctylfluorene) and poly(methyl methacrylate) , 2002 .

[96]  J. Northrup,et al.  Atomic and electronic structure of polymer organic semiconductors: P3HT, PQT, and PBTTT , 2007 .

[97]  Itaru Osaka,et al.  Advances in molecular design and synthesis of regioregular polythiophenes. , 2008, Accounts of chemical research.

[98]  T. Kowalewski,et al.  Highly disordered polymer field effect transistors: N-alkyl dithieno[3,2-b:2',3'-d]pyrrole-based copolymers with surprisingly high charge carrier mobilities. , 2008, Journal of the American Chemical Society.

[99]  Antonio Facchetti,et al.  Semiconductors for organic transistors , 2007 .

[100]  A. Poruba,et al.  Optical absorption by defect states in organic solar cells , 2006 .

[101]  P. Blom,et al.  Unified description of charge-carrier mobilities in disordered semiconducting polymers. , 2005, Physical review letters.

[102]  G. Koller,et al.  α-Sexithiophene on Cu(1 1 0) and Cu(1 1 0)–(2 × 1)O: An STM and NEXAFS study , 2009 .

[103]  J. Rabolt,et al.  Kinetics of Chain Organization in Ultrathin Poly(di-n-hexylsilane) Films† , 1996 .

[104]  R. J. Kline,et al.  Morphology and Charge Transport in Conjugated Polymers , 2006 .

[105]  F. Spano,et al.  Modeling disorder in polymer aggregates: the optical spectroscopy of regioregular poly(3-hexylthiophene) thin films. , 2005, The Journal of chemical physics.

[106]  P. Heremans,et al.  Analytic model of hopping mobility at large charge carrier concentrations in disordered organic semiconductors: Polarons versus bare charge carriers , 2007 .

[107]  N. Tessler,et al.  Mobility spatial distribution function : Comparative method for conjugated polymers/molecules , 2006 .

[108]  Tsu-Jae King,et al.  Effective density‐of‐states distributions for accurate modeling of polycrystalline‐silicon thin‐film transistors , 1994 .

[109]  Wi Hyoung Lee,et al.  Liquid-crystalline semiconducting copolymers with intramolecular donor-acceptor building blocks for high-stability polymer transistors. , 2009, Journal of the American Chemical Society.

[110]  Alberto Salleo,et al.  Solution Based Self‐Assembly of an Array of Polymeric Thin‐Film Transistors , 2007 .

[111]  P. Heremans,et al.  Analytic model of carrier mobility in doped disordered organic semiconductors , 2005 .

[112]  U. Pietsch,et al.  Thickness Dependence of the Crystalline Structure and Hole Mobility in Thin Films of Low Molecular Weight Poly(3-hexylthiophene) , 2008 .

[113]  A. Wee,et al.  Solvent Effects on Chain Orientation and Interchain π‐Interaction in Conjugated Polymer Thin Films: Direct Measurements of the Air and Substrate Interfaces by Near‐Edge X‐ray Absorption Spectroscopy , 2007 .

[114]  Y. Tao,et al.  Highly Oriented Growth of p-Sexiphenyl Molecular Nanocrystals on Rubbed Polymethylene Surface , 2005 .

[115]  Ullrich Scherf,et al.  Charge carrier transport in conjugated polymers , 1999 .

[116]  Noam Rappaport,et al.  Charge Transport in Disordered Organic Materials and Its Relevance to Thin‐Film Devices: A Tutorial Review , 2009 .

[117]  K. Müllen,et al.  Field-effect transistors based on a benzothiadiazole-cyclopentadithiophene copolymer. , 2007, Journal of the American Chemical Society.

[118]  Harald Ade,et al.  Trends in the Carbonyl Core (C 1S, O 1S) → π*C=O Transition in the Near-Edge X-ray Absorption Fine Structure Spectra of Organic Molecules , 2002 .

[119]  D. Bradley,et al.  Formation of a Ground‐State Charge‐Transfer Complex in Polyfluorene//[6,6]‐Phenyl‐C61 Butyric Acid Methyl Ester (PCBM) Blend Films and Its Role in the Function of Polymer/PCBM Solar Cells , 2007 .

[120]  D. Gundlach,et al.  Arbitrary Density of States in an Organic Thin-Film Field-Effect Transistor Model and Application to Pentacene Devices , 2007, IEEE Transactions on Electron Devices.

[121]  Intrinsic hole mobility and trapping in a regioregular poly(thiophene) , 2004, cond-mat/0407502.

[122]  Bradley,et al.  Photoexcited states in poly(p-phenylene vinylene): Comparison with trans,trans-distyrylbenzene, a model oligomer. , 1990, Physical review. B, Condensed matter.

[123]  Donal D. C. Bradley,et al.  X-ray diffraction study of the structure of thin polyfluorene films , 2002 .

[124]  Jiang,et al.  Two-dimensional electronic excitations in self-assembled conjugated polymer nanocrystals , 2000, Science.

[125]  Wei Chen,et al.  Low-temperature scanning tunneling microscopy and near-edge X-ray absorption fine structure investigation of epitaxial growth of F16CuPc thin films on graphite , 2009 .

[126]  M. Ballauff.  Stiff‐Chain Polymers—Structure, Phase Behavior, and Properties , 1989 .

[127]  C. Daniel Frisbie,et al.  Surface potential profiling and contact resistance measurements on operating pentacene thin-film transistors by Kelvin probe force microscopy , 2003 .

[128]  A. Troisi,et al.  Prediction of the Absolute Charge Mobility of Molecular Semiconductors: the Case of Rubrene , 2007 .

[129]  R. Friend,et al.  Exciton migration in a polythiophene: probing the spatial and energy domain by line-dipole Forster-type energy transfer. , 2005, The Journal of chemical physics.

[130]  Robert A. Street,et al.  Polymer thin-film transistors with chemically modified dielectric interfaces , 2002 .

[131]  Alberto Salleo,et al.  Lamination method for the study of interfaces in polymeric thin film transistors. , 2004, Journal of the American Chemical Society.

[132]  N. Gisin,et al.  Spectral hole-burning spectroscopy in Nd3+: YVO4 , 2008 .

[133]  E. Kramer,et al.  Accounting for Auger Yield Energy Loss for Improved Determination of Molecular Orientation Using Soft X-Ray Absorption Spectroscopy , 2002 .

[134]  Eric K. Lin,et al.  Critical Role of Side-Chain Attachment Density on the Order and Device Performance of Polythiophenes , 2007 .

[135]  Mm Martijn Wienk,et al.  Substitution and preparation effects on the molecular-scale morphology of PPV films , 2005 .

[136]  D. Campbell,et al.  Optical absorption from polarons in a model of polyacetylene , 1983 .

[137]  P. Thomas,et al.  Equilibrium and non-equilibrium transport in band tails , 1993 .

[138]  H. Sirringhaus,et al.  Relative importance of polaron activation and disorder on charge transport in high-mobility conjugated polymer field-effect transistors , 2007 .

[139]  J. Pflaum,et al.  Effect of Molecular Weight and Annealing of Poly(3‐hexylthiophene)s on the Performance of Organic Field‐Effect Transistors , 2004 .

[140]  Youngsuk Jung,et al.  Surface Characteristics of Polyfluorene Films Studied by Polarization-Dependent NEXAFS Spectroscopy , 2005 .

[141]  Lisa R. Pattison,et al.  Probing the Ordering of Semiconducting Fluorene−Thiophene Copolymer Surfaces on Rubbed Polyimide Substrates by Near-Edge X-ray Absorption Fine Structure , 2006 .

[142]  M. Casu,et al.  Growth mode and molecular orientation of phthalocyanine molecules on metal single crystal substrates: A NEXAFS and XPS study , 2006 .

[143]  J. Villarrubia.  Algorithms for Scanned Probe Microscope Image Simulation, Surface Reconstruction, and Tip Estimation , 1997, Journal of research of the National Institute of Standards and Technology.

[144]  C. Frisbie,et al.  Observation of Unusual Homoepitaxy in Ultrathin Pentacene Films and Correlation with Surface Electrostatic Potential , 2009 .

[145]  B. Grévin,et al.  Scanning Tunneling Microscopy Investigations of Self‐Organized Poly(3‐hexylthiophene) Two‐Dimensional Polycrystals , 2003 .

[146]  H. Bässler.  Charge Transport in Disordered Organic Photoconductors a Monte Carlo Simulation Study , 1993 .

[147]  A. Schenning,et al.  Supramolecular Electronic Coupling in Chiral Oligothiophene Nanostructures , 2006 .

[148]  S. H. A. Chen,et al.  Molecular Packing in Crystalline Poly(9,9-di-n-octyl-2,7-fluorene) , 2004 .

[149]  D. Ginger,et al.  Space charge limited current measurements on conjugated polymer films using conductive atomic force microscopy. , 2008, Nano letters.

[150]  T. Ohta,et al.  In-situ measurement of molecular orientation of the pentacene ultrathin films grown on SiO2 substrates , 2006 .

[151]  A. Morpurgo,et al.  Tunable Fröhlich polarons in organic single-crystal transistors , 2006, Nature materials.

[152]  Eric K. Lin,et al.  Significant dependence of morphology and charge carrier mobility on substrate surface chemistry in high performance polythiophene semiconductor films , 2007 .

[153]  R. J. Kline,et al.  Thin Film Microstructure of a Solution Processable Pyrene-Based Organic Semiconductor , 2008 .

[154]  Jenny Clark,et al.  Determining exciton bandwidth and film microstructure in polythiophene films using linear absorption spectroscopy , 2009, 0903.1670.

[155]  Gilles Horowitz,et al.  Organic Field‐Effect Transistors , 1998 .

[156]  Gilles Horowitz,et al.  GATE VOLTAGE DEPENDENT MOBILITY OF OLIGOTHIOPHENE FIELD-EFFECT TRANSISTORS , 1999 .

[157]  M. Torkkeli,et al.  Influence of molecular weight on self-organization, uniaxial alignment and surface morphology of hairy-rodlike polyfluorene in thin films , 2004 .

[158]  Maxim Shkunov,et al.  Liquid-crystalline semiconducting polymers with high charge-carrier mobility , 2006, Nature materials.

[159]  D. Käfer,et al.  Evolution of pentacene films on Ag(1 1 1): Growth beyond the first monolayer , 2007 .

[160]  M. Toney,et al.  Highly oriented crystals at the buried interface in polythiophene thin-film transistors , 2006 .

[161]  A. Pron,et al.  Effect of macromolecular parameters and processing conditions on supramolecular organisation, morphology and electrical transport properties in thin layers of regioregular poly(3-hexylthiophene) , 2006 .

[162]  J. Nelson,et al.  Simulating charge transport in tris(8-hydroxyquinoline) aluminium (Alq(3)). , 2008, Physical chemistry chemical physics : PCCP.

[163]  David S. Germack,et al.  Substrate-dependent interface composition and charge transport in films for organic photovoltaics , 2009 .

[164]  M. Vissenberg,et al.  Theory of the field-effect mobility in amorphous organic transistors , 1998, cond-mat/9802133.

[165]  R. Street,et al.  Influence of gap states on the electrical stability of pentacene thin film transistors , 2008 .

[166]  M. Chabinyc.  X‐ray Scattering from Films of Semiconducting Polymers , 2008 .

[167]  S. Mannsfeld,et al.  Microstructure of Oligofluorene Asymmetric Derivatives in Organic Thin Film Transistors , 2008 .

[168]  M. Toney,et al.  Charge‐Transport Anisotropy Due to Grain Boundaries in Directionally Crystallized Thin Films of Regioregular Poly(3‐hexylthiophene) , 2009 .

[169]  Gilles Horowitz,et al.  Theory of the organic field-effect transistor , 1999 .

[170]  Harald Ade,et al.  A Quantitative Study of PCBM Diffusion during Annealing of P3HT:PCBM Blend Films , 2009 .

[171]  M. Shkunov,et al.  Optical Signature of Delocalized Polarons in Conjugated Polymers , 2001 .

[172]  Jenny Clark,et al.  Molecular-weight dependence of interchain polaron delocalization and exciton bandwidth in high-mobility conjugated polymers , 2006 .

[173]  Z. Bao,et al.  Synthetic chemistry for ultrapure, processable, and high-mobility organic transistor semiconductors. , 2001, Accounts of chemical research.

[174]  L. De Schepper,et al.  Observation of the subgap optical absorption in polymer-fullerene blend solar cells , 2006 .

[175]  Jenny Clark,et al.  Determining exciton coherence from the photoluminescence spectral line shape in poly(3-hexylthiophene) thin films. , 2009, The Journal of chemical physics.

[176]  Andrew J. Moad,et al.  Molecular Basis of Mesophase Ordering in a Thiophene-Based Copolymer , 2008 .

[177]  Mena-Osteritz,et al.  Two-Dimensional Crystals of Poly(3-Alkyl- thiophene)s: Direct Visualization of Polymer Folds in Submolecular Resolution This work was supported by the European Union in the framework of Frequent-Esprit 24793. , 2000, Angewandte Chemie.

[178]  A. Troisi,et al.  Computational study of the structure and charge-transfer parameters in low-molecular-mass P3HT. , 2009, The journal of physical chemistry. B.

[179]  V. Subramanian,et al.  Direct Correlation of Organic Semiconductor Film Structure to Field‐Effect Mobility , 2005 .

[180]  David Beljonne,et al.  Interchain interactions in conjugated materials: The exciton model versus the supermolecular approach , 2000 .

[181]  Martin Brinkmann,et al.  Orientation of Regioregular Poly(3‐hexylthiophene) by Directional Solidification: A Simple Method to Reveal the Semicrystalline Structure of a Conjugated Polymer , 2006 .

[182]  K. Kubota,et al.  Extensive studies on pi-stacking of poly(3-alkylthiophene-2,5-diyl)s and poly(4-alkylthiazole-2,5-diyl)s by optical spectroscopy, NMR analysis, light scattering analysis, and X-ray crystallography , 1998 .

[183]  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.

[184]  Maxim Shkunov,et al.  Optical spectroscopy of field-induced charge in self-organized high mobility poly(3-hexylthiophene) , 2001 .

[185]  Zhenan Bao,et al.  Organic single-crystal field-effect transistors , 2007 .

[186]  A. Boccara,et al.  Photothermal deflection spectroscopy and detection. , 1981, Applied optics.

[187]  Markus Schwoerer,et al.  Subgap absorption in poly(p-phenylene vinylene) , 2001 .

[188]  Jenny Clark,et al.  Role of intermolecular coupling in the photophysics of disordered organic semiconductors: aggregate emission in regioregular polythiophene. , 2007, Physical review letters.

[189]  R. J. Kline,et al.  Semiconducting Thienothiophene Copolymers: Design, Synthesis, Morphology, and Performance in Thin‐Film Organic Transistors , 2009 .

[190]  Gilles Horowitz,et al.  Organic thin film transistors: From theory to real devices , 2004 .

[191]  Zhenan Bao,et al.  Effect of Mesoscale Crystalline Structure on the Field‐Effect Mobility of Regioregular Poly(3‐hexyl thiophene) in Thin‐Film Transistors , 2005 .

[192]  F. Zheng,et al.  Orientation of pentacene molecules on SiO2: from a monolayer to the bulk. , 2007, The Journal of chemical physics.

[193]  M. Torkkeli,et al.  The Influence of the Molecular Weight on the Thermotropic Alignment and Self-Organized Structure Formation of Branched Side Chain Hairy-Rod Polyfluorene in Thin Films , 2005 .

[194]  Y. Tao,et al.  Molecular orientation of evaporated pentacene films on gold: alignment effect of self-assembled monolayer. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[195]  N. Tessler,et al.  Spatially dispersive transport: A mesoscopic phenomenon in disordered organic semiconductors , 2007 .

[196]  Robert A. Street,et al.  Surface‐Induced Self‐Encapsulation of Polymer Thin‐Film Transistors , 2006 .

[197]  Henning Sirringhaus,et al.  Control of roughness at interfaces and the impact on charge mobility in all-polymer field-effect transistors , 2008 .

[198]  T. Faber,et al.  The applicability of the transport-energy concept to various disordered materials , 1997 .

[199]  Mario Leclerc,et al.  A calorimetric study of the phase transitions in poly(3-hexylthiophene) , 1995 .

[200]  K. Stevenson,et al.  High‐Resolution Characterization of Pentacene/Polyaniline Interfaces in Thin‐Film Transistors , 2006 .

[201]  Alessandro Troisi,et al.  Charge transport in semiconductors with multiscale conformational dynamics. , 2009, Physical review letters.

[202]  David S. Germack,et al.  Controlling the orientation of terraced nanoscale "ribbons" of a poly(thiophene) semiconductor. , 2009, ACS nano.

[203]  Fred Endicott,et al.  Effects of the surface roughness of plastic-compatible inorganic dielectrics on polymeric thin film transistors , 2007 .

[204]  Ronald Österbacka,et al.  Spectroscopic Studies of Photoexcitations in Regioregular and Regiorandom Polythiophene Films , 2002 .