PMMA/High-k Self-assembled TiO2/PMMA Multi-layer Gate Dielectric for P3HT Organic Field Effect Transistors
Article Sidebar
Main Article Content
Abstract
In this work, a multi-layer structure of poly(methyl methacrylate)/ titanium dioxide/poly(methyl methacrylate) (PMMA/TiO₂ /PMMA; PTP) was proposed as a top-gate insulator for P3HT-based organic field-effect transistors (OFETs). Adding a TiO₂ interlayer as a high dielectric constant (high-k) material into PMMA film enables the modification of the dielectric constant of the multi-layers PTP film. The content of TiO₂ in the PTP film, which can be varied by changing the number of soaking cycles in TiO₂ solution, plays a crucial rule in modifying the dielectric constant of the PTP film. The higher the TiO₂ content used in the PTP film, the higher the dielectric constant of PTP film can be obtained. However, using high TiO₂ content led to a reduction in the dielectric constant of the PTP film due to leakage current induced by the agglomeration of TiO₂. The utilization of the top-gate insulator containing TiO₂ significantly enhanced several P3HT-OFETs characteristics, e.g., an increase in the Ion/Ioff ratio, and a decrease in the threshold voltage. However, the use of the PTP top-gate insulator with a high content of TiO₂ resulted in regressions in the OFETs characteristics, such as a decrease in carrier mobility and reduction in the Ion/Ioff ratio. OFETs operating at the optimum conditions of the PTP gate-insulator, with PTP thickness of 225 nm and RMS roughness of 20.0 nm, provided a dielectric constant of 7.13, a threshold voltage of -8.49 V, a saturation mobility of 2.2× 10-4 cm²V-1s-1, Ion/Ioff ratio of 37.9, and a subthreshold slope of 0.39 V/decade.
Keywords: organics field-effect transistors; dielectric constant; TiO2; PMMA; P3HT
*Corresponding author: Tel.: (+66) 2 329 8000
Fax: (+66) 2 329 8265
E-mail: [email protected]
Article Details
Copyright Transfer Statement
The copyright of this article is transferred to Current Applied Science and Technology journal with effect if and when the article is accepted for publication. The copyright transfer covers the exclusive right to reproduce and distribute the article, including reprints, translations, photographic reproductions, electronic form (offline, online) or any other reproductions of similar nature.
The author warrants that this contribution is original and that he/she has full power to make this grant. The author signs for and accepts responsibility for releasing this material on behalf of any and all co-authors.
Here is the link for download: Copyright transfer form.pdf
References
Torsi, L., Dodabalapur, A., Rothberg, L.J., Fung A.W.P. and Katz, H.E., 1996. Intrinsic transport properties and performance limits of organic field-effect transistors. Science, 272, 1462-1464.
Koutsiakia, C., Kaimakamisa, T., Zachariadisa, A., Papamichaila, A., Kamarakia, C., Fachourib S., Gravalidisa, C., Laskarakisa, A. and Logothetidisa, S., 2019. Efficient combination of roll-to-roll compatible techniques towards the large area deposition of a polymer dielectric film and the solution-processing of an organic semiconductor for the field-effect transistors fabrication on plastic substrate. Organic Electronics, 73, 231-239.
Zschieschang, U., Ante, F., Yamamoto, T., Takimiya, K., Kuwabara, H., Ikeda, M., Sekitani, T., Someya, T., Kern, K. and Klauk, H., 2010. Flexible low-voltage organic transistors and circuit based on a high-mobility organic semiconductor with good air stability. Advanced Materials, 22, 982-985.
Ismail, L.N., Samsul, S., Musa, M.Z. and Norsabrina, S., 2018. Fabrication of p-type organic field effect transistor using PMMA:TiO2 as nanocomposite dielectric layer. IOP Conference Series: Materials Science and Engineering, 340(1), 012005, https://doi.org/10.1088/1757-899X/340/1/012005.
Deman, A.L. and Tardy, J., 2006. Stability of pentacene organic field effect transistors with a low-k polymer/high-k oxide two-layer gate dielectric. Materials Science and Engineering: C, 26, 421-426.
Noh, Y.-Y. and Sirringhaus, H., 2009. Ultra-thin polymer gate dielectrics for top-gate polymer field effect transistors. Organic Electronics, 10, 174-180.
Facchetti, A., Yoon, M. and Marks, T.J., 2005. Gate dielectrics for organic field effect transistors: new opportunities for organic electronics. Advanced Materials, 17, 1705-1725.
Herlogsson, L., Crispin, X., Robinson, N.D., Sandberg, M., Hagel, O., Gustafsson, G. and Berggren, M., 2007. Low-voltage polymer field-effect transistors gated via a proton conductor. Advanced Materials, 19, 97-101.
Yim, K., Yong, Y., Lee, J., Lee, K., Nahm, H.H., Yoo, J., Lee, C., Hwang, C.S. and Han, S., 2015. Novel high-κ dielectrics for next-generation electronic devices screened by automated ab initio calculations. NPG Asia Materials, 7(6), e190, https://doi.org/10.1038/am.2015.57.
Veres, J., Ogier, S. and Lloyd, G., 2004. Gate insulator in organic field-effect transistors. Chemistry of Materials, 16, 4543-4555.
Chen, F., Chu, C., He, J., Yang, Y. and Lin, J., 2004. Organic thin-film transistors with nanocomposite dielectric gate insulator. Applied Physics Letters, 85, 3295-3297.
Chen, F., Chuang, C., Lin, Y., Kung, L., Chen, T. and Shieh, H. D., 2006. Low-voltage organic thin-film transistors with polymeric nanocomposite dielectrics. Organic Electronics, 7, 435-439.
Yang, F., Chang, K., Hsu, M. and Liu, C., 2008. Low-operative-voltage polymer transistor with solution processed low-k polymer/high-k metal-oxide bilayer insulators. Organic Electronics, 9, 925-929.
Yang, F., Hsu, M., Hwang, G. and Chang, K., 2010. High-performance poly(3-hexylthiophene) top-gate transistors incorporating TiO2 nanocomposite dielectrics. Organic Electronics, 11, 81-88.
Wypych, A., Bobowska, I., Tracz, M., Opasinska, A., Kadlubowski, S., Krzywania-Kaliszewska, A., Grobelny, J. and Wojciechowski, P., 2014. Dielectric properties and characterization of titanium dioxide obtained by different chemistry methods. Journal of Nanomaterials, 2014, https://doi.org/10.1155/2014/124814.
Feng, Y., Yin, J., Chen, M., Song, M., Su, B. and Lei, Q., 2013. Effect of nano-TiO2 on the polarization process of polyimide-TiO2 composites. Materials Letters, 96, 113-116.
Abouelhassan, S., 2010. Investigation of the dielectric properties and thermodynamic parameters of (50 − x) P2O5 -xAgI -40Ag2O -10Fe2O3 ionic glass. Chinese Journal of Physics, 48, 650-661.
Harun, M. H., Saion, E., Kassim, A., Mahmud, E., Hussain, M. Y. and Mustafa, I. S., 2009. Dielectric Properties of Poly (vinyl alcohol)/polypyrrole composite polymer films. Journal for the Advancement of Science and Arts, 1, 9-16.
Sung, S., Park, S., Lee, W., Son, J., Kim, C. and Yoon, M., 2015. Low-voltage flexible organic electronics based on high performance sol-gel titanium dioxide dielectric. ACS Applied Materials and Interfaces, 7, 7456-7461.
Hoshino, S., Yoshida, M., Uemura, S., Kodzasa, T., Takada, N., Kamata, T. and Yase, K., 2004. Influence of moisture on device characteristics of polythiophene-based field-effect transistors. Journal of Applied Physics, 95, 5088-5093.
Chabinyc, M.L., Endicott, F., Vogt, B.D., DeLongchamp, D.M., Lin, E.K., Wu, Y., Liu, P. and Ong, B.S., 2006. Effects of humidity on unencapsulated poly(thiophene) thin-film transistors. Applied Physics Letters, 88(11), 113514, https://doi.org/10.1063/1.2181206.
Horowitz, G., Hajlaoui, R., Bouchriha, Bourguiga, H.R. and Hajlaoui, M., 1998. The concept of “Threshold-Voltage” in organic field-effect transistors. Advanced Materials, 10, 923-927.
Ismail, L.N., Zulkefle, H., Sauki, N.S.A.M., Zain, A., Herman, S.H. and Mahmood, M.R., 2013. Characterization of metal-insulator-semiconductor capacitor with poly(methyl methacrylate): titanium dioxide as insulator. Japanese Journal of Applied Physics, 52(6S), https://doi.org/10.7567/JJAP.52.06GG02.