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Influence of morphological disorder on in- and out-of-plane charge transport in conjugated polymer films

  • Anton Li (a1), Ban Xuan Dong (a1) and Peter F. Green (a1)

Thin films of the conjugated polymer poly(3-hexylthiophene) (P3HT) of different morphological structures were fabricated using both conventional spin-casting and the matrix-assisted pulsed laser evaporation (MAPLE). Films deposited by MAPLE exhibit inhomogeneous morphologies comprised globular subfeatures with dimensions of the order of 100 nm. We show that whereas the in-plane carrier mobilities of MAPLE-deposited films (8.3 × 10−3 cm2/V/s) are comparable with those of spin-cast analogs (5.5 × 10−3 cm2/V/s), the out-of-plane mobilities are an order of magnitude lower (4.1 × 10−4 cm2/V/s versus 2.7 × 10−3 cm2/V/s). Both in- and out-of-plane carrier transport characteristics of MAPLE-deposited films indicate a broad density of states and high carrier trap concentration. Optical absorbance spectroscopy not only corroborates a high degree of energetic disorder in MAPLE-deposited films, but also suggests that the P3HT chains possess average conjugation lengths comparable with spin-cast counterparts. Our findings, rationalized in terms of the Gaussian Disorder Model, describing carrier transport in an environment characterized by both positional and energetic disorder, provide important perspectives on the extent to which disorder impacts mechanisms of charge transport in conjugated polymers.

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* Address all correspondence to Peter F. Green at
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1. Wu, P.K., Ringeisen, B.R., Callahan, J., Brooks, M., Bubb, D.M., Wu, H.D., Piqué, A., Spargo, B., McGill, R.A., and Chrisey, D.B.: The deposition, structure, pattern deposition, and activity of biomaterial thin-films by matrix-assisted pulsed-laser evaporation (MAPLE) and MAPLE direct write. Thin Solid Films 398–399, 607614 (2001).
2. Caricato, A.P. and Luches, A.: Applications of the matrix-assisted pulsed laser evaporation method for the deposition of organic, biological and nanoparticle thin films: a review. Appl. Phys. A 105, 565582 (2011).
3. McGill, R.A., Chrisey, D.B., Pique, A., and Mlsna, T.E.: Matrix-assisted pulsed-laser evaporation (MAPLE) of functionalized polymers: applications with chemical sensors. SPIE Proc. 3274, 255266 (1998).
4. Piqué, A., McGill, R.A., Chrisey, D.B., Leonhardt, D., Mslna, T.E., Spargo, B.J., Callahan, J.H., Vachet, R.W., Chung, R., and Bucaro, M.A.: Growth of organic thin films by the matrix assisted pulsed laser evaporation (MAPLE) technique. Thin Solid Films 355–356, 536541 (1999).
5. Chrisey, D.B., Piqué, A., McGill, R.A., Horwitz, J.S., Ringeisen, B.R., Bubb, D.M., and Wu, P.K.: Laser deposition of polymer and biomaterial films. Chem. Rev. 103, 553576 (2003).
6. Guo, Y., Morozov, A., Schneider, D., Chung, J.W., Zhang, C., Waldmann, M., Yao, N., Fytas, G., Arnold, C.B., and Priestley, R.D.: Ultrastable nanostructured polymer glasses. Nat. Mater. 11, 337343 (2012).
7. Shepard, K.B., Guo, Y., Arnold, C.B., and Priestley, R.D.: Nanostructured morphology of polymer films prepared by matrix assisted pulsed laser evaporation. Appl. Phys. A 110, 771777 (2013).
8. Gutiérrez-Llorente, A., Horowitz, G., Pérez-Casero, R., Perrière, J., Fave, J.L., Yassar, A., and Sant, C.: Growth of polyalkylthiophene films by matrix assisted pulsed laser evaporation. Org. Electron. 5, 2934 (2004).
9. Pate, R., Lantz, K.R., and Stiff-Roberts, A.D.: Tabletop resonant infrared matrix-assisted pulsed laser evaporation of light-emitting organic thin films. IEEE J. Sel. Top. Quantum Electron. 14, 10221030 (2008).
10. McCormick, R.D., Lenhardt, J., and Stiff-Roberts, A.D.: Effects of emulsion-based resonant infrared matrix assisted pulsed laser evaporation (RIR-MAPLE) on the molecular weight of. Polymers 4, 341354 (2012).
11. Ge, W., Atewologun, A., and Stiff-Roberts, A.D.: Hybrid nanocomposite thin films deposited by emulsion-based resonant infrared matrix-assisted pulsed laser evaporation for photovoltaic applications. Org. Electron. 22, 98107 (2015).
12. Greer, J.A.: Design challenges for matrix assisted pulsed laser evaporation and infrared resonant laser evaporation equipment. Appl. Phys. A 105, 661671 (2011).
13. Ge, W., McCormick, R.D., Nyikayaramba, G., and Stiff-Roberts, A.D.: Bulk heterojunction PCPDTBT: PC71BM organic solar cells deposited by emulsion-based, resonant infrared matrix-assisted pulsed laser evaporation. Appl. Phys. Lett. 104, 223901 (2014).
14. Leveugle, E. and Zhigilei, L.V.: Molecular dynamics simulation study of the ejection and transport of polymer molecules in matrix-assisted pulsed laser evaporation. J. Appl. Phys. 102, 074914 (2007).
15. Shepard, K.B., Arnold, C.B., and Priestley, R.D.: Transport and stability of laser-deposited amorphous polymer Nanoglobules. ACS Macro Lett. 3, 10461050 (2014).
16. Shepard, K.B., Arnold, C.B., and Priestley, R.D.: Origins of nanostructure in amorphous polymer coatings via matrix assisted pulsed laser evaporation. Appl. Phys. Lett. 103, 123105 (2013).
17. Spano, F.C.: Modeling disorder in polymer aggregates: the optical spectroscopy of regioregular poly(3-hexylthiophene) thin films. J. Chem. Phys. 122, 234701 (2005).
18. Spano, F.C.: Absorption in regio-regular poly(3-hexyl)thiophene thin films: Fermi resonances, interband coupling and disorder. Chem. Phys. 325, 2235 (2006).
19. Clark, J., Chang, J.-F., Spano, F.C., Friend, R.H., and Silva, C.: Determining exciton bandwidth and film microstructure in polythiophene films using linear absorption spectroscopy. Appl. Phys. Lett. 94, 163306 (2009).
20. Gierschner, J., Huang, Y.-S., Averbeke, B.V., Cornil, J., Friend, R.H., and Beljonne, D.: Excitonic versus electronic couplings in molecular assemblies: the importance of non-nearest neighbor interactions. J. Chem. Phys. 130, 044105 (2009).
21. Spano, F.C. and Silva, C.: H- and J-aggregate behavior in polymeric semiconductors. Annu. Rev. Phys. Chem. 65, 477500 (2014).
22. Dinelli, F., Murgia, M., Levy, P., Cavallini, M., Biscarini, F., and de Leeuw, D.M.: Spatially correlated charge transport in organic thin film transistors. Phys. Rev. Lett. 92, 116802 (2004).
23. Salleo, A., Kline, R.J., DeLongchamp, D.M., and Chabinyc, M.L.: Microstructural characterization and charge transport in thin films of conjugated polymers. Adv. Mater. 22, 38123838 (2010).
24. Joseph Kline, R., McGehee, M.D., and Toney, M.F.: Highly oriented crystals at the buried interface in polythiophene thin-film transistors. Nat. Mater. 5, 222228 (2006).
25. Sirringhaus, H.: 25th anniversary article: organic field-effect transistors: the path beyond amorphous silicon. Adv. Mater. 26, 13191335 (2014).
26. Himmelberger, S. and Salleo, A.: Engineering semiconducting polymers for efficient charge transport. MRS Commun. FirstView, 113 (2015).
27. Juška, G., Arlauskas, K., Viliūnas, M., and Kočka, J.: Extraction current transients: new method of study of charge transport in microcrystalline silicon. Phys. Rev. Lett. 84, 49464949 (2000).
28. Huang, B., Glynos, E., Frieberg, B., Yang, H., and Green, P.F.: Effect of thickness-dependent microstructure on the out-of-plane hole mobility in poly(3-hexylthiophene) films. ACS Appl. Mater. Interfaces 4, 52045210 (2012).
29. Blom, P.W.M., de Jong, M.J.M., and Vleggaar, J.J.M.: Electron and hole transport in poly(p-phenylene vinylene) devices. Appl. Phys. Lett. 68, 33083310 (1996).
30. Kirchartz, T.: Influence of diffusion on space-charge-limited current measurements in organic semiconductors. Beilstein J. Nanotechnol. 4, 180188 (2013).
31. Juška, G., Arlauskas, K., Viliūnas, M., Genevičius, K., Österbacka, R., and Stubb, H.: Charge transport in π-conjugated polymers from extraction current transients. Phys. Rev. B 62, R16235R16238 (2000).
32. Bässler, H.: Charge transport in disordered organic photoconductors a Monte Carlo simulation study. Phys. Status Solidi B 175, 1556 (1993).
33. Mozer, A.J. and Sariciftci, N.S.: Negative electric field dependence of charge carrier drift mobility in conjugated, semiconducting polymers. Chem. Phys. Lett. 389, 438442 (2004).
34. Dong, B.X., Huang, B., Tan, A., and Green, P.F.: Nanoscale orientation effects on carrier transport in a low-band-gap polymer. J. Phys. Chem. C 118, 1749017498 (2014).
35. Noriega, R., Rivnay, J., Vandewal, K., Koch, F.P.V., Stingelin, N., Smith, P., Toney, M.F., and Salleo, A.: A general relationship between disorder, aggregation and charge transport in conjugated polymers. Nat. Mater. 12, 10381044 (2013).
36. Mollinger, S.A., Krajina, B.A., Noriega, R., Salleo, A., and Spakowitz, A.J.: Percolation, tie-molecules, and the microstructural determinants of charge transport in Semicrystalline conjugated polymers. ACS Macro Lett. 4, 708712 (2015). doi:10.1021/acsmacrolett.5b00314.
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