Sains Malaysiana 39(4)(2010): 615–620

Dependence of Band Structure and Carrier Concentration of Metallic (13,13) and Semiconducting (13,0) Single Wall Carbon Nanotube on Temperature

(Kebergantungan Struktur Jalur dan Kepekatan Pembawa untuk Nanotiub Karbon Berdinding Tunggal yang Bersifat Logam (13,13) dan Semikonduktor (13,0) Terhadap Suhu)

J. Karamdel^1,2,*, M. Damghanian¹, F. Razaghian², C.F. Dee¹ & B. Yeop Majlis¹

¹Institute of Microengineering and Nanoelectronics (IMEN)

University Kebangsaan Malaysia, 43600, Bangi, Selangor, D.E., Malaysia

²Electrical Department, Faculty of Engineering

Islam Azad University-South Tehran Branch, No. 209 North Iranshahr Ave Tehran, Iran

Received: 28 August 2009 / Accepted: 17 November 2009

ABSTRACT

The electronic band structure, density of states (DOS) and carrier concentration of a (13,13) metallic and a (13,0) semiconducting Single Wall Carbon Nanotube (SWCNT) have been estimated and simulated by using the Fermi-Dirac distribution function. The energy dispersion E(k) relation for metallic SWCNT near the minimum energy is linear and the Fermi level was independent of temperature (T). On the other hand for semiconducting SWCNT the E(k) relation is parabolic. The normalized Fermi-Energy (E_F – E_C) in the nondegenerate regime is a weak (logarithmic) function of carrier concentration and varies linearly with T. In the degenerate condition, the Fermi level was independent of T and was a strong function of carrier concentration.

Keywords: Band structure; carbon nano-tube; carrier statistic; Fermi level

ABSTRAK

Struktur jalur elektronik,  ketumpatan keadaan dan kepekatan pembawa bagi nanotiub karbon berdinding tunggal (SWCNT) yang bersifat logam dan semikonduktor telah dianggarkan dengan menggunakan fungsi taburan Fermi-Dirac. Hubungan E(k) berdekatan dengan tenaga minimum adalah mendatar dan aras Fermi adalah bebas daripada pengaruh suhu (T) untuk SWCNTs yang bersifat logam. Manakala, untuk SWCNTs yang bersifat semikonduktor, hubungan E(k) adalah parabolik. Tenaga Fermi-ternormal (E_F – E_C) dalam regim tak-degenerat mempunyai fungsi ketumpatan pembawa (logaritma) yang lemah dan berubah secara linear dengan T. Dalam keadaan degenerat, aras Fermi tidak bergantung dengan T dan adalah satu fungsi yang bergantung kuat dengan kepekatan pembawa.

Kata kunci: Aras Fermi; nanotiub karbon; statistik pembawa; struktur jalur

REFERENCES

Akinwande, D., Nishi, Y. & Wong, H.S.P. 2008. An Analytical Derivation of the Density of States, Effective Mass and Carrier Density for Achiral Carbon Nanotubes. IEEE Trans. Electron Devices 55(1): 289-297.

Arora, V.K. 2000. Quantum engineering of nanoelectronic devices: the role of quantum emission in limiting drift velocity and diffusion coefficient. Microelectronic J. 31(11-12): 853-859.

Arora, V.K. 2006. Failure of Ohm’s Law: Its Implications on the Design of Nanoelectronics Devices and Circuits. Proceeding, Int Conf. on Microelectronic. Belgrade, Serbia and Montenegro: 17-24.

Chen, B.H., Wei, J.H., Lo, P.Y., Pei1, Z.W., Chao, T.S., Lin, H.C. & Huang, T.Y. 2006. Novel Method of Converting Metallic-Type Carbon Nanotubes to Semiconducting-Type Carbon Nanotube Field-Effect Transistors Jpn. J. Appl. Phys. 45: 3680-3685.

Chen, Z., Du, X., Du, M.H., Rancken, C.D., Cheng, H.-P. & Rinzler, A.G. 2003. Bulk Separative Enrichment in Metallic or Semiconducting Single-Walled Carbon Nanotubes. Nano Lett. 3(9): 1245-1249.

Datta, S. 2005. Quantum Transport Atom to transistor. UK: Cambridge Press.

Karamdel, J., Ahmadi, M.T., Damghanian, M., Yeop Majlis, B., Dee, C.F. & Ismail, R. 2009. Analysis and Simulation of Carriers Statistic for a Semi-conducting Single Wall Carbon Nanotube. Material Research Innovations 13(3): 211-213.

Lundstrom, M.S. & Guo, J. 2006. Nanoscale Transistors. New York: Springer.

Neamen, D.A. 2003. Semiconductor Physics and Devices. New York: Mc Graw Hill.

Vaseashta, A. 2003. Field-emission characteristics of carbon nanotubes and their applications in photonic devices. Mater in Elec. 14(10-12): 653-656.

Wilder, J.W.G., Venema, L.C., Rinzler, A.G., Smalley, R.E. & Dekker, C. 1998. Electronic structure of atomically resolved carbon nanotubes. Nature 391-6662: 59-62.

*Corresponding author; email: jkaramdel@yahoo.com