Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-14T06:58:24.742Z Has data issue: false hasContentIssue false

Fabrication of RR-P3HT-based TFTs using low-temperature PECVD silicon nitride passivation

Published online by Cambridge University Press:  01 February 2011

Sarswati Koul
Affiliation:
Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
Yuri Vygranenko
Affiliation:
Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
Flora Li
Affiliation:
Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
Andrei Sazonov
Affiliation:
Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
Arokia Nathan
Affiliation:
Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
Get access

Abstract

Regioregular poly(3-hexylthiophene) (RR-P3HT) is a commercially available semiconducting polymer. Its high processability makes it favorable for fabrication of organic thin film transistors (OTFTs). Depending on the processing technique and device configuration, the field effect mobility of this polymer ranges from 0.01 to 0.1 cm2/Vs. The mobility also shows a correlation with the choice of gate dielectric material. The most commonly reported dielectric materials for OTFTs are SiO2, Al2O3 and Ta2O5. In this work, we report a new fully encapsulated top-gate RR-P3HT-based TFT structure with a-SiNx implemented as the gate dielectric and passivation material. The fabrication process enables realization of discrete transistors and transistor circuits through four consecutive photolithographic steps. The process is compatible for various substrates including Corning glass, Si wafers, and any appropriate plastic substrates. This paper addresses a number of critical technological issues such as substrate surface treatment to improve film adhesion, optimal spin coating conditions for uniform polymer film formation, preparation of device quality a-SiNx films by plasma-enhanced chemical vapor deposition (PECVD) at 75°C substrate temperature, and a tailored etch process for patterning of the polymer film. Current-voltage characteristics of the fabricated transistors are analyzed to evaluate the quality of the polymer/a-SiNx interface.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 Sirringhaus, H., Tessler, N. and Friend, R., Science 280, 1741 (1998).Google Scholar
2 Bao, Z., Dodabapalur, A., Lovinger, A. J.. Appl. Phys. Lett. 69, 4108 (1996).Google Scholar
3 Burgi, L., Richards, T. J., Friend, R. H., and Sirringhaus, H., J. Appl. Phys. 94, 6129 (2003).Google Scholar
4 Wang, G., Swensen, J., Moses, D. and Heeger, A.J., J. Appl. Phys. 93, 6137 (2003).Google Scholar
5 Gundlach, D. J., Lin, Y. Y., Jackson, T. N., Nelson, S. F., Schlom, D. G., IEEE Electron Device Lett., 18, 87 (1997).Google Scholar
6 Bao, Z., Lovinger, A. J., Chem. Matter. 11, 2607 (1999).Google Scholar
7 Steudel, S., Vusser, S. D., Jonge, S. D., Janssen, D., Verlaak, S., Genow, J. and Heremans, P., Appl. Phys. Lett. 85, 4400 (2004).Google Scholar
8 Dodabapalur, A., Torsi, L., Katz, H. E., Science 268, 270 (1995).Google Scholar
9 Torsi, L., Dodabapalur, A., Katz, H. E., J. Appl. Phys. 78, 1088 (1995).Google Scholar
10 Shin, J. H., Jung, L. Y., Pyo, S. W., Kim, Y. K., Thin Solid Films 441, 284 (2003).Google Scholar
11 Park, S. Y., Park, M. and Lee, H. H., Appl. Phys. Lett. 85, 2283 (2004).Google Scholar
12 Ashkenasy, G., Cahen, D., Cohen, R., Shanzer, A. and Vilan, A., Acc. Chem. Res. 35, 121 (2002).Google Scholar
13 Ishii, H., Sugiyama, K., Ito, E. and Seki, K., Adv. Matter. 11, 605 (1999).Google Scholar
14 Kobayashi, S., Nishikawa, T., Takenobu, T., Mori, S., Shimoda, T., Mitani, T., Shimotani, H., Yoshimoto, N., Ogawa, S., Iwasa, Y., Nature Materials 3, 317 (2004).Google Scholar
15 Salleo, A., Chabinyo, M. L., Yang, M. S. and Street, R. A., Appl. Phys. Lett. 81, 4383 (2002); S. Hayase, Pog. Poly. Sci. 28, 359 (2003).Google Scholar
16 Street, R. A., Ed., Technology and Applications of Hydrogenated Amorphous Silicon, New York: Springer (2000).Google Scholar
17 Sazonov, A. and McArthur, C., J. Vac. Sci. Technol. A 22, 2052 (2004).Google Scholar
18 Hoshino, S., Yoshida, M., Uemura, S., Kodzasa, T., Takada, N., Kamata, T. and Yase, Kiyoshi, J. Appl. Phys. 95, 5088 (2004).Google Scholar
19 Abdou, M. S. A., Orfino, F. P., Xie, Z. W., Deen, M. J. and Holdcroft, S., Adv. Mater. 6, 838 (1994).Google Scholar
20 Wang, S., Fundamentals of Semiconductors: Theory and Device Physics, Englewood Cleffs, NJ: Prentice Hall (1989); R. F. Pierret, Field Effect devices, Reading, MA: Addison- Wesley (1990).Google Scholar