Abstract
Al doped SnO2 thin films have been synthesized by a sol-gel dip coating technique with different percentages of Al on glass and silicon substrates. X-ray diffraction studies confirmed the proper phase formation in the films and atomic percentage of aluminium doping in the films was obtained by energy dispersive X-ray studies. SEM studies showed the particle sizes lying in the range 100–150 nm for the undoped films and it decreased with increase of Al doping. Optical transmittance spectra of the films showed high transparency (∼80%) in the visible region and the transparency increases with the increase of Al doping in the films. The direct allowed bandgap of the films have been measured for different Al concentration and they lie within the range of 3.87–4.21 eV. FTIR studies depicted the presence of Sn–O, Al–O, bonding within the films. The room temperature electrical conductivities of the films are obtained in the range of 0.21 S cm−1 to 1.36 S cm−1 for variation of Al doping in the films 2.31–18.56%. Room temperature Seebeck coefficients, SRT of the films were found in the range +56.0 μVK−1 to −23.3 μVK−1 for variation of Al doping in the films 18.56–8.16%. It is observed that the Seebeck coefficient changes its sign at 12.05% of Al in the films indicating that below 12.05% of Al doping, SnO2:Al behaves as an n-type material and above this percentage it is a p-type material.
Similar content being viewed by others
References
Ginley DS, Bright C (2000) MRS Bull 25:15
Lewis BJ, Paine DC (2000) MRS Bull 25:22
Omura K, Veluchamy P, Tsuji M, Nishio T, Murojono D (1999) J Electrochem Soc 146:2113
Orel B, Lavrencic-Stangar U, Kalcher K (1994) J Electrochem Soc 141:L127
Laverty SJ, Feng H, Maguire P (1997) J Electrochem Soc 144:2165
Hamberg Z, Svesson JSEM, Eriksson TS, Granqvist CG, Arrenius P, Narin F (1987) Appl Opt 26:2131
Tadeev AV, Delabouglise G, Labeau M (1998) Mater Sci Engg B 57:76
Phatak G, Lal R (1994) Thin Solid Films 245:17
Chopra KL, Major S, Pandya DK (1983) Thin Solid Films 102:1
Pizzini S, Butta N, Narducci D, Palladino M (1989) J Electrochem Soc 136:1945
Mattox DM (1991) Thin Solid Films 204:25
Gong H, Wang Y, Luo Yi (2000) Appl Phys Lett 76:3959
Hiramatsu Hidenori, Orita Masahiro, Hirano Masahiro, Ueda Kazushige, Hosono Hideo (2002) J Appl Phys 91:9177
Ohta H, Orita M, Hirano M, Yagi I, Ueda K, Hosono H (2002) J Appl Phys 91:3074
Popova LI, Mikhailov MG, Gueorguiev VK, Shopov A (1990) Thin Solid Films 186:107
Proscia J, Gordon RG (1992) Thin Solid Films 214:175
Suh S, Zhang Z, Chu WK, Hoffman DM (1999) Thin Solid Films 345:240
Czapla A, Kusior E, Bucko M (1989) Thin Solid Films 182:15
He YS, Campbell JC, Murphy RC, Arendt MF, Swinnea JS (1993) J Mater Res 8:3131
Veluchamy P, Tsuji M, Nishio T, Aramoto T, Higuchi H, Kumazawa S, Shibutani S, Nakajima J, Arita T, Ohyma H, Hanafusa A, Hibino T, Omura K (2001) Sol Eng Mater Sol Cells 67:179
Terrier C, Chatelon JP, Roger JA, Berjoan R, Dubois C (1997) J Sol-Gel Sci Technol 10:75
Burgard D, Goebbert C, Nass R (1998) J Sol-gel Sci Technol 13:789
Cachet H, Gamard A, Campet G, Jousseaume B, Toupance T (2001) Thin Solid Films 388:41
Putz J, Gasparro D, Aegerter MA (1998) J Sol-Gel Sci Technol 13:1005
Banerjee AN, Kundoo S, Saha P, Chattopadhyay KK (2003) Journal of Sol-Gel Sci Technol 28:105
Ji Z, He Z, Song Y, Liu K, Xiang Y (2004) Thin Solid Films 460:324
Mohammad-Mehdi, Bagheri-Mohagheghi, Shokooh-Saremi M (2004) J Phys D: Appl Phys 37:1248
JCPDS powder Diffraction File card 5-0467
Ghosh PK, Maity R, Chattopadhyay KK (2004) Solar Energy Mater Solar Cells 81:279
Gu Z, Liang P, Liu X, Zhang W, Le Y (2000) J Sol-Gel Sci Technol 18:159
Nakamoto K (ed) (1963) Infrared spectra of inorganic and coordinated compounds. John Wiley & Sons, Inc., p 76, 86
Nakamoto K (1986) Infrared and Raman spectra of inorganic and coordination compounds, 4th edn. John Wiley & Sons, Inc, p 103
Eriksson TS, Granqvist CG (1986) J Appl Phys 60(6):2081
Pankove (ed) (1971) Optical processes in semiconductors. Prentice-Hall, Inc, p 34
Dominquez JE, Pan XQ, Fu L, Van Rompay PA, Zhang Z, Nees JA, Pronko PP (2002) J Appl Phys 91:1060
Chopra KL (1969) Thin film phenomena. McGraw-Hill, New York
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Ahmed, S.F., Khan, S., Ghosh, P.K. et al. Effect of Al doping on the conductivity type inversion and electro-optical properties of SnO2 thin films synthesized by sol-gel technique. J Sol-Gel Sci Technol 39, 241–247 (2006). https://doi.org/10.1007/s10971-006-7808-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10971-006-7808-x