Advertisement

Journal of Computational Electronics

, Volume 17, Issue 3, pp 1315–1323 | Cite as

Design and performance investigation of short channel bottom-contact organic thin-film transistors

  • Farkhanda Ana
  • Najeeb-ud Din
Article

Abstract

This paper presents an investigation on the design of organic thin-film transistors (OTFTs) with short channel lengths required to achieve higher integration density organic circuits for various DC and RF applications. The DC and AC performance parameters of an OTFT with channel lengths 5, 2, 1.5, 1.0, 0.9 and 0.7 \(\upmu \hbox {m}\) have been evaluated through carefully calibrated two-dimensional numerical simulation. The designed OTFT uses pentacene as the active layer in the bottom-contact configuration. The various performance parameter metrics, i.e., threshold voltage (\({V}_\mathrm{TH}\)), transconductance (\({G}_\mathrm{M}\)), gain (\({A}_\mathrm{V}\)), I\(_\mathrm{ON}\)/I\(_\mathrm{OFF}\), DIBL, cutoff frequency (\({f}_\mathrm{T}\)) and breakdown voltage (\({V}_\mathrm{BR}\)), have been evaluated. The results have revealed that OTFTs with short channel lengths show improved performance compared to long channel transistors. The second-order effects of V\(_\mathrm{TH}\) roll-off and DIBL are less pronounced in OTFTs. Results show that the \(\mathrm{V}_\mathrm{TH}\) reduces only by 10.73% from \(L=5\,\upmu \hbox {m}\) to \(L=0.7 \,\upmu \hbox {m}\). The results have shown that OTFTs have a high I\(_\mathrm{ON}\)/I\(_\mathrm{OFF}\) ratio of the order of 10\(^{13}\) and thus are effective for fast switching applications. The cutoff frequency of the simulated device for \(L=0.7\,\upmu \) m is 2.3 GHz suggesting the application of OTFTs for RF applications. The role of trap states on the device conduction has also been investigated. The simulation study has revealed that OTFTs exhibit well-defined mobility degradation and impact ionization behavior which becomes pronounced for channel lengths below 1 \(\upmu \hbox {m}\). Further the capacitive behavior of the designed device has been evaluated, and it has been observed that the device capacitance can be defined from the MOSFET theory except for the role of trap states.

Keywords

DIBL Impact ionization Mobility degradation Organic thin-film transistors Pentacene Poole–Frenkel mobility Threshold voltage 

References

  1. 1.
    Forrest, S.R.: The path to ubiquitous and low-cost organic electronic appliances on plastic. Nature 428, 911–918 (2004)CrossRefGoogle Scholar
  2. 2.
    Pray, L.A.: Organic electronics for a better tomorrow: innovation, accessibility, sustainability. Royal Society of Chemistry, http://www.rsc.org/globalassets/04-campaigning-outreach/policy/research-policy/global-challenges/organic-electronics-for-a-better-tomorrow.pdf, April 08 (2013)
  3. 3.
    Reese, C., Roberts, M., Ling, M., Bao, Z.: Organic thin film transistors. Mater. Today 7(9), 20–27 (2004)CrossRefGoogle Scholar
  4. 4.
    Wondmagegn, W., Pieper, R.: Simulation of top-contact pentacene thin film transistor. J. Comput. Electron. 8, 19–24 (2009)CrossRefGoogle Scholar
  5. 5.
    Shekar, C., Lee, T., Rhee, S.W.: Organic thin film transistors, materials, processes and devices. Korean J. Chem. Eng. 21, 267–287 (2004)CrossRefGoogle Scholar
  6. 6.
    Klauk, H., Halik, M., Zschieschang, U., Schmid, G., Radlik, W.: High-mobility polymer gate dielectric pentacene thin film transistors. J. Appl. Phys. 92, 5259 (2002)CrossRefGoogle Scholar
  7. 7.
    Mittal, P., Yadav, A., Negi, Y.S., Singh, R.K., Tripathi, N.: Parameter extraction and analysis of pentacene thin film transistor with different insulators. In: Proceedings of the International Conference on Advances in Electronics, Electrical and Computer Science Engineering- EEC (2012)Google Scholar
  8. 8.
    Gupta, D., Katiyar, M., Gupta, D.: An analysis of the difference in behavior of top and bottom contact organic thin film transistors using device simulation. Org. Electron. 10, 775–784 (2009)CrossRefGoogle Scholar
  9. 9.
    Necliudov, P.V., Shur, M.S., Gundlach, D.J., Jackson, T.N.: Modeling of organic thin film transistors of different designs. J. Appl. Phys. 88, 6594 (2000)CrossRefGoogle Scholar
  10. 10.
    Garnier, F., Hajlaoui, R., Yasser, A., Srivastava, P.: All polymer field-effect transistors realized by printing techniques. Science 265, 1684 (1994)CrossRefGoogle Scholar
  11. 11.
    Mittal, P., Kumar, B., Negi, Y.S., Kaushik, B.K., Singh, R.K.: Channel length variation effect on performance parameters of organic field effect transistors. Microelectron. J. 43, 985–994 (2012)CrossRefGoogle Scholar
  12. 12.
    Locci, S., Morana, M., Orgiu, E., Bonfiglio, A., Lugli, P.: Modeling of short-channel effects in organic thin-film transistors. IEEE Trans. Electron Devices 55, 2561–2567 (2008)CrossRefGoogle Scholar
  13. 13.
    Torsi, L., Dodabalapur, A., Katz, H.E.: An analytical model for short channel organic thinfilm transistors. J. Appl. Phys. 78, 1088 (1995)CrossRefGoogle Scholar
  14. 14.
    Gupta, D., Jeon, N., Yoo, S.: Modeling the electrical characteristics of TIPS-pentacene thin-film transistors: effect of contact barrier, field-dependent mobility, and traps. Org. Electron. 9, 1026–1031 (2008)CrossRefGoogle Scholar
  15. 15.
    Sharma, A., Yadav, S., Kumar, P., Chaudhuri, S.R., Ghosh, S.: Defect states and their energetic position and distribution in organic molecule semiconductors. Appl. Phys. Lett. 102, 143301 (2013)CrossRefGoogle Scholar
  16. 16.
    Stallinga, P., Gomes, H.L.: Thin-film field-effect transistors: the effects of traps on the bias and temperature dependence of field-effect mobility, including the Meyer-Neldel rule. Org. Electron. 7, 592–599 (2006)CrossRefGoogle Scholar
  17. 17.
    Ana, F., Najeeb-ud, D.: Simulation study of the electrical behavior of bottom contact organic thin-film transistor’s. IEEE Xplore.  https://doi.org/10.1109/ICEmElec.2014.7151133
  18. 18.
    Ana, F., Najeeb-ud, D.: Effect of mobility degradation on the device performance of organic thin-film transistor’s. IEEE Xplore.  https://doi.org/10.1109/TENCON.2016.7848654
  19. 19.
    Mottaghi, M., HorowitzI, G.: Field-induced mobility degradation in pentacene thin-film transistors. Org. Electron. 7, 445–606 (2006)CrossRefGoogle Scholar
  20. 20.
    Braga, D., Horowitz, G.: Subthreshold regime in rubrene single-crystal organic transistors. Appl. Phys. A Mater. Sci. Process. 95, 193–201 (2009)CrossRefGoogle Scholar
  21. 21.
    Streetman, B.G., Banerjee, S.: Solid State Electronic Devices, 6th Edition. Printice Hall, London.Google Scholar
  22. 22.
    Mittal, P., Negi, Y.S., Singh, R.K.: Impact of source and drain contact thickness on the performance of organic thin film transistors. J. Semicond. 35, 124002 (2014)CrossRefGoogle Scholar
  23. 23.
    Klauk, H., Zschieschang, U.: Low-voltage organic thin-film transistors with large transconductance. J. Appl. Phys. 102, 074514 (2007)CrossRefGoogle Scholar
  24. 24.
    Yaglioglu, B., Agostinelli, T., Cain, P., Mijalkovic, S., Nejim, A.: Parameter extraction and evaluation of UOTFT model for organic thin-film transistor circuit design. J. Disp. Technol. 9, 890–894 (2013)CrossRefGoogle Scholar
  25. 25.
    Anand, S., Amin, S.I., Sarin, R.K.: Analog performance investigation of dual electrode based doping-less tunnel FET. J. Comput. Electron. (2015)Google Scholar
  26. 26.
    Tang, Z., Wie, C.R.: Capacitance-voltage characteristics and device simulation of bias temperature stressed a-Si: H TFTs. Solid-State Electron. 54, 259–267 (2009)CrossRefGoogle Scholar
  27. 27.
    Weste, N.H.E., Harris, D., Banerjee, A.: CMOS VLSI Design: A Circuits and Systems Perspective, 3rd edition. Pearson Education Asia (2006)Google Scholar
  28. 28.
    Zaki, T., Rodel, R., Letzkus, F., Richter, H., Zschieschang, U., Klauk, H., Burghartz, J.N.: AC characterization of organic thin-film transistors with asymmetric gate-to-source and gate-to-drain overlaps. Org. Electron. 14, 1318–1322 (2013)CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Electronics and CommunicationNational Institute of TechnologySrinagarIndia

Personalised recommendations