Sains Malaysiana 41(8)(2012): 1023–1028

Effect of TMAH Etching Duration on the Formation of Silicon Nanowire

Transistor Patterned by AFM Nanolithography

(Kesan Tempoh Punaran TMAH ke atas Penghasilan Transistor Nanodawai Silikon

Tercorak Menggunakan Nanolitografi Mikroskop Daya Atom)

Sabar D. Hutagalung* & Kam C. Lew

School of Materials and Mineral Resources Engineering, Engineering Campus

Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia

Received: 25 January 2010 / Accepted: 19 September 2011

ABSTRACT

Atomic force microscopy (AFM) lithography was applied to produce nanoscale pattern for silicon nanowire transistor fabrication. This technique takes advantage of imaging facility of AFM and the ability of probe movement controlling over the sample surface to create nanopatterns. A conductive AFM tip was used to grow the silicon oxide nanopatterns on silicon on insulator (SOI) wafer. The applied tip-sample voltage and writing speed were well controlled in order to form pre-designed silicon oxide nanowire transistor structures. The effect of tetra methyl ammonium hydroxide (TMAH) etching duration on the oxide covered silicon nanowire transistor structure has been investigated. A completed silicon nanowire transistor was obtained by removing the oxide layer via hydrofluoric acid etching process. The fabricated silicon nanowire transistor consists of a silicon nanowire that acts as a channel with source and drain pads. A lateral gate pad with a nanowire head was fabricated very close to the channel in the formation of transistor structures.

Keywords: Etching duration; nanolotography AFM; silicon nanowire; TMAH; transistor

ABSTRAK

Litografi mikroskop daya atom (AFM) telah diguna untuk menghasilkan corak skala nano untuk fabrikasi transistor nanowayar silikon. Teknik ini menggunakan kemudahan pengimejan AFM dan keupayaan mengawal pergerakan kuar di atas permukaan sampel untuk mewujudkan nanocorak. Hujung AFM yang konduktif telah digunakan untuk menghasilkan wafer nanocorak oksida silikon pada silikon di atas penebat (SOI). Voltan pada hujung sampel yang dikenakan dan kelajuan tulisan dikawal dengan baik untuk menghasilkan strukutur pra-bentuk transistor nanowayar silikon oksida. Kesan tempoh punaran tetra metil ammonium hidroksida (TMAH) terhadap oksida yang dilindungi struktur transistor nanowayar silikon telah dikaji. Transistor nanowayar silikon telah diperoleh dengan mengeluarkan lapisan oksida melalui proses punaran asid hidrofluorik. Transistor nanowayar silikon terdiri daripada nanowayar silikon yang bertindak sebagai saluran dengan pad sumber dan salir. Pad get sisi dengan kepala nanowayar telah direka bentuk berhampiran dengan saluran dalam pembentukan struktur transistor.

Kata kunci: Nanowayar silikon; nanolitografi AFM; tempoh punaran; TMAH; transistor

REFERENCES

Cervenka, J., Kalousek, R., Bartosik, M., Skoda, D., Tomanec, O. & Sikola, T. 2006. Fabrication of nanostructures on Si(100) and GaAs(100) by local anodic oxidation. Applied Surface Science 253: 2373-2378.

Chien, F.S.S., Hsieh, W.F., Gwo, S., Vladar, A.E. & Dagata, J.A. 2002. Silicon nanostructures fabricated by scanning probe oxidation and tetra-methyl ammonium hydroxide etching. Journal of Applied Physics 91: 12-16.

Choi, S.H., Jeong, K.J., Choi, J.S., Cho, T.Y. & Chun, H.G. 1998. A study on the removal of silicon native oxide for ULSI devices A study on the removal of silicon native oxide for ULSI devices. Journal of Korea Physical Society 33: S99-S103.

Dalla Betta, G.F., Ronchin, S., Zoboli, A. & Zorzi, N. 2008. High-performance PIN photodiodes on TMAH thinned silicon wafers. Microelectronics Journal 39: 1485-1490.

Fang, T.H. 2004. Mechanisms of nanooxidation of Si(100) from atomic force microscopy. Microelectronics Journal 35: 701-707.

Fu, E.S., Wang, X. & Williams, E.D. 1999. Characterization of structures fabricated by atomic force microscope lithography. Surface Science 438: 58-67.

Giesbers, A.J.M., Zeitler, U., Neubeck, S., Freitag, F., Novoselov, K.S. & Maan, J.C. 2008. Nanolithography and manipulation of graphene using an atomic force microscope. Solid State Communications 147: 366-369.

Held, R., Heinzel, T., Studerus, P. & Ensslin, K. 1998. Nanolithography by local anodic oxidation of metal films using an atomic force microscope. Physica E 2: 748- 752.

Hu, X. & Hu, X. 2005. Analysis of the process of anodization with AFM. Ultramicroscopy 105: 57-61.

Hutagalung, S.D., Darsono, T., Yaacob, K.A. & Ahmad, Z.A. 2007. Effects of tip voltage and writing speed on the formation of silicon oxide nanodots patterned by scanning probe lithography. Journal of Scanning Probe Microscopy 2: 28-31.

Kuramochi, H., Ando, K. & Yokoyama, H. 2003. Effect of humidity on nano-oxidation of p-Si(001) surface. Surface Science 542: 56-63.

Lazzarino, M., Mori, G., Sorba, L., Ercolani, D., Biasiol, G., Heun, S. & Locatelli, A. 2006. Chemistry and formation process of Ga(Al)As oxide during local anodic oxidation nanolithography. Surface Scicence 600: 3739-3743.

Lee, S., Kim, J., Shin, W.S., Lee, H.J., Koo, S. & Lee, H. 2004. Fabrication of nanostructures using scanning probe microscope lithography. Materials Science and Engineering C 24: 3-9.

Lee, S.K., Lee, S.Y., Rogdakis, K., Jang, C.O., Kim, D.J., Bano, E. & Zekentes, K. 2009. Si nanowire p-FET with asymmetric source-drain I - V characteristics. Solid State Communications 149: 461-463.

Lew, K.C. & Hutagalung, S.D. 2010. Silicon nanowire transistor fabricated by AFM nanolithography followed by wet chemical etching process. International Journal of Nanoscience 9: 289-293.

Luo, G., Xie, G., Zhang, Y., Zhang, G., Zhang, Y., Carlberg, P., Zhu, T. & Liu, Z. 2006. Scanning probe lithography for nanoimprinting mould fabrication. Nanotechnology 17: 3018-3022.

Salem, B., Dhalluin, F., Abed, H., Baron, T., Gentile, P., Pauc, N. & Ferret, P. 2009. Self-connected horizontal silicon nanowire field effect transistor. Solid State Communications 149: 799-801.

Suk, S.D., Yeo, K.H., Cho, K.H., Li, M., Yeoh, Y.Y., Lee, S.Y., Kim, S.M., Yoon, E.J., Kim, M.S., Oh, C.W., Kim, S.H., Kim, D.W. & Park, D. 2008. High-performance twin silicon nanowire MOSFET (TSNWFET) on bulk Si wafer. IEEE Transaction on Nanotechnology 7: 181-184.

Xie, X.N., Chung, H.J., Sow, C.H. & Wee, A.T.S. 2006. Nanoscale materials patterning and engineering by atomic force microscopy nanolithography. Material Science and Engineering R 54: 1-48.

Xuefeng, D. 2005. Microfabrication using bulk wet etching with TMAH, M.S. Thesis, Department of Physics, McGill University (unpublished)

Yoon, C., Kang, J., Yeom, D., Jeong, D.Y. & Kim, S. 2008. Comparison of electrical characteristics of back- and top-gate Si nanowire field-effect transistors. Solid State Communications 148: 293-296.

*Corresponding author; email: mrsabar@eng.usm.my