journal article Open Access Mar 30, 2016

Charge carrier coherence and Hall effect in organic semiconductors

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Abstract
AbstractHall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.
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References
28
[1]
da Silva Filho, D. A., Kim, E.-G. & Bredas, J.-L. Transport Properties in the Rubrene Crystal: Electronic Coupling and Vibrational Reorganization Energy. Adv. Mater. 17, 1072–1076 (2005). 10.1002/adma.200401866
[2]
Troisi, A. & Orlandi, G. Charge-Transport Regime of Crystalline Organic Semiconductors: Diffusion Limited by Thermal Off-Diagonal Electronic Disorder. Phys. Rev. Lett. 96, 086601 (2006). 10.1103/physrevlett.96.086601
[3]
Cheung, D. L. & Troisi, A. Modelling charge transport in organic semiconductors: from quantum dynamics to soft matter. Phys. Chem. Chem. Phys. 10, 5941–5952 (2008). 10.1039/b807750a
[4]
Ciuchi, S. & Fratini, S. Electronic transport and quantum localization effects in organic semiconductors. Phys. Rev. B 86, 245201 (2012). 10.1103/physrevb.86.245201
[5]
Coropceanu, V. et al. Charge transport in organic semiconductors. Chem. Rev. 107, 926–952 (2007). 10.1021/cr050140x
[6]
Hannewald, K. & Bobbert, P. A. Ab initio theory of charge-carrier conduction in ultrapure organic crystals. Appl. Phys. Lett. 85, 1535–1537 (2004). 10.1063/1.1776335
[7]
Podzorov, V. Organic single crystals: Addressing the fundamentals of organic electronics. MRS Bulletin 38, 15–24 (2013). 10.1557/mrs.2012.306
[8]
Density of bulk trap states in organic semiconductor crystals: Discrete levels induced by oxygen in rubrene

C. Krellner, S. Haas, C. Goldmann et al.

Physical Review B 2007 10.1103/physrevb.75.245115
[9]
Noriega, R. et al. A general relationship between disorder, aggregation and charge transport in conjugated polymers. Nature Mater. 12, 1038–1044 (2013). 10.1038/nmat3722
[10]
Mastrogiovanni, D. D. T. et al. Oxygen Incorporation In Rubrene Single Crystals. Sci. Reports 4, 4753 (2014). 10.1038/srep04753
[11]
Najafov, H., Mastrogiovanni, D., Garfunkel, E., Feldman, L. C. & Podzorov, V. Photon-assisted oxygen diffusion and oxygen-related traps in organic semiconductors. Adv. Mater. 23, 981–985 (2011). 10.1002/adma.201004239
[12]
Northrup, J. E. & Chabinyc, M. L. Gap states in organic semiconductors: hydrogen- and oxygen-induced states in pentacene. Phys. Rev. B 68, 041202 (2003). 10.1103/physrevb.68.041202
[13]
Chen, Y. & Podzorov, V. Bias Stress Effect in “Air-Gap” Organic Field-Effect Transistors. Adv. Mater. 24, 2679–2684 (2012). 10.1002/adma.201200455
[14]
Kloc, C., Simpkins, P. G., Siegrist, T. & Laudise, R. A. Physical vapor growth of centimeter-sized crystals of alpha-hexathiophene. J. Cryst. Growth 182, 416–427 (1997). 10.1016/s0022-0248(97)00370-9
[15]
Ciavatti, A. et al. Toward Low-Voltage and Bendable X-Ray Direct Detectors Based on Organic Semiconducting Single Crystals. Adv. Mater. 27, 7213–7220 (2015). 10.1002/adma.201503090
[16]
Podzorov, V., Menard, E., Rogers, J. A. & Gershenson, M. E. Hall Effect in the Accumulation Layers on the Surface of Organic Semiconductors. Phys. Rev. Lett. 95, 226601 (2005). 10.1103/physrevlett.95.226601
[17]
Uemura, T. et al. Temperature dependence of the Hall effect in pentacene field-effect transistors: Possibility of charge decoherence induced by molecular fluctuations. Phys. Rev. B 85, 035313 (2012). 10.1103/physrevb.85.035313
[18]
Chang, J.-F. et al. Hall-Effect Measurements Probing the Degree of Charge-Carrier Delocalization in Solution-Processed Crystalline Molecular Semiconductors. Phys. Rev. Lett. 107, 066601 (2011). 10.1103/physrevlett.107.066601
[19]
Wang, S., Ha, M., Manno, M., Frisbie, C. D. & Leighton, C. H. Hopping transport and the Hall effect near the insulator–metal transition in electrochemically gated poly(3-hexylthiophene) transistors. Nature Commun. 3, 1210 (2012). 10.1038/ncomms2213
[20]
Yamashita, Y. et al. Mobility exceeding 10 cm2/Vs in donor-acceptor polymer transistors with band-like charge transport. Chem. Mater. 28, 420–424 (2016). 10.1021/acs.chemmater.5b04567
[21]
Chen, Y., Yi, H. T. & Podzorov, V. High-resolution ac measurements of the Hall effect in organic field-effect transistors. Phys. Rev. Applied 5, 034008 (2016). 10.1103/physrevapplied.5.034008
[22]
Fukami, T. et al. Correlation between thermal fluctuation effects and phase coherence factor in carrier transport of single-crystal organic semiconductors. Appl. Phys. Lett. 106, 143302 (2015). 10.1063/1.4916734
[23]
Holstein, T. Hall Effect in Impurity Conduction. Phys. Rev. 124, 1329–1347 (1961). 10.1103/physrev.124.1329
[24]
Klein, R. S. Investigation of the Hall effect in impurity-hopping conduction. Phys. Rev. B 31, 2014–2021 (1985). 10.1103/physrevb.31.2014
[25]
Takeya, J., Tsukagoshi, K., Aoyagi, Y., Takenobu, T. & Iwasa, Y. Hall Effect of Quasi-Hole Gas in Organic Single-Crystal Transistors. Jpn. J. Appl. Phys. 44, L1393–1396 (2005). 10.1143/jjap.44.l1393
[26]
Podzorov, V., Pudalov, V. M. & Gershenson, M. E. Field-effect transistors on rubrene single crystals with parylene gate insulator. Appl. Phys. Lett. 82, 1739–1741 (2003). 10.1063/1.1560869
[27]
Podzorov, V. et al. Intrinsic charge transport on the surface of organic semiconductors. Phys. Rev. Lett. 93, 086602 (2004). 10.1103/physrevlett.93.086602
[28]
Troisi, A. Prediction of the Absolute Charge Mobility of Molecular Semiconductors: the Case of Rubrene. Adv. Mater. 19, 2000–2004 (2007). 10.1002/adma.200700550
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Published
Mar 30, 2016
Vol/Issue
6(1)
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H. T. Yi, Y. N. Gartstein, V. Podzorov (2016). Charge carrier coherence and Hall effect in organic semiconductors. Scientific Reports, 6(1). https://doi.org/10.1038/srep23650