Abstract

Optical properties of Sn-doped In2O 3 (ITO) have been studied in the optical range of 0.412μm. A deposition has been made on BK7 glass, magnesium fluoride, sapphire, and zinc sulfide substrates. The layers have been characterized by their optical properties, DC electrical sheet resistivity, and Hall mobility. Sheet resistivity lies in the range of 6.8318Ω/sq for thicknesses between 16 and 280  nm. The best carrier mobility is obtained on BK7 and sapphire substrates, up to 50cm2/V   s. The material shows good infrared transparency in the 35μm range on magnesium fluoride and 0.44μm on sapphire, and it is usable for practical applications up to 12μm on zinc sulfide. Simulations have been carried out for optical indices and spectra calculations. The Drude model has been used to exploit the results in either direction: from electrical measured data to the simulation of optical spectra and indices, and from measured optical spectra to simulated optical indices and electrical parameters (mobility, carrier density). Hall mobility is considered a worthy and convenient material quality criteria for materials aimed at optics.

© 2007 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |

  1. I. Hamberg and C. G. Granqvist, "Evaporated Sn-doped In2O3 films: basic optical properties and applications to energy-efficient windows," J. Appl. Phys. 60, R123-R159 (1986).
    [CrossRef]
  2. Y. Shigesato, S. Takaki, and T. Haranoh, "Electrical and structural properties of low resistivity tin-doped indium oxide films," J. Appl. Phys. 71, 3356-3364 (1992).
    [CrossRef]
  3. S. Vigneron, X. Castel, G. Legeay, and J. Pinel, "Propriétés des couches minces d'ITO: influence de la proportion d'oxygène," in 8èmes Journées de Caractérisation Microondes et Matériaux, La Rochelle, France, (2004), paper G3.
  4. J. C. C. Fan and F. J. Bachner, "Properties of Sn-doped In2O3 films prepared by RF sputtering," J. Electrochem. Soc. 122, 1719-1725 (1975).
    [CrossRef]
  5. J. C. C. Fan, "Preparation of Sn-doped In2O3 (ITO) films at low deposition temperatures by ion-beam sputtering," Appl. Phys. Lett. 34, 515-517 (1979).
    [CrossRef]
  6. Wen-Fa Wu and Bi-Shiou Chiou, "Properties of radio-frequency magnetron sputtered ITO films without in-situ substrate heating and post-deposition annealing," Thin Solid Films 247, 201-207 (1994).
    [CrossRef]
  7. J. C. C. Fan, "Sputtered films for wavelength-selective applications," Thin Solid Films 80, 125-136 (1981).
    [CrossRef]
  8. C. Coutal, A. Azéma, and J.-C. Roustan, "Fabrication and characterization of ITO thin films deposited by excimer laser evaporation," Thin Solid Films 288, 248-253 (1996).
    [CrossRef]
  9. Tze-Chiang Chen, Tso-ping Ma, R. C. Barker, and W. Hasan, "Properties and applications of infrared transparent and electrically conductive In2O3 thin film," Proc. SPIE 430, 270-273 (1983).
  10. C. F. Bohren and D. R. Huffman, "Classical Theories of Optical Constants," in Absorption and Scattering of Light by Small Particles (Wiley, 1983).
  11. R. E. Hummel, Electronic Properties of Materials (Springer Verlag, 1992).
  12. CS Developpements, 1 rue Madeleine Crenon, F-92330 Sceaux (France). E-mail: csurfdvt@aol.com.
  13. W. L. Wolfe and G. J. Zissis, The Infrared Handbook (Infrared Information Analysis Center, Environmental Research Institute of Michigan, 1989).
  14. Rohm and Haas Company Advanced Materials, 185 New Boston Street, Woburn, MA 01801.
  15. F. Hanus, A. Jardin, and L. D. Laude, "Pulsed laser deposition of high quality ITO films," Appl. Surf. Sci. 96-98, 807-810 (1996).
    [CrossRef]
  16. C. Kittel, Introduction to Solid State Physics, 7th ed. (Wiley, 1996).
  17. L. J. van der Pauw, "A method of measuring specific resistivitiy and Hall effect of discs of arbitrary shape," Philips Res. Rep. 13, 1-9 (1958).
  18. F. M. Smits, "Measurement of Sheet Resistivities with the Four Point Probe," Bell Syst. Tech. J. 711-718 (May 1958).
  19. R. A. Synowicki, "Spectroscopic ellipsometry characterization of indium tin oxide film microstructure and optical constants," Thin Solid Films 313-314, 394-397 (1998).
    [CrossRef]
  20. S. Laux, N. Kaiser, A. Zöller, R. Götzelmann, H. Lauth, and H. Bernitzki, "Room-temperaure deposition of indium tin oxide thin films with plasma ion-assisted evaporation," Thin Solid Films 335, 1-5 (1998).
    [CrossRef]
  21. H. El Rhaleb, E. Benamar, M. Rami, J. P. Roger, A. Hakam, and A. Ennaoui, "Spectroscopic ellipsometry studies of index profile of indium tin oxide films prepared by spray pyrolysis," Appl. Surf. Sci. 201, 138-145 (2002).
    [CrossRef]
  22. T. Nagatomo, Y. Maruta, and O. Omoto, "Electrical and optical properties of vacuum-evaporated indium-tin oxide films with high electron mobility," Thin Solid Films 192, 17-25 (1990).
    [CrossRef]
  23. J. R. Bellingham, W. A. Phillips, and C. J. Adkins, "Intrinsic performance limits in transparent conducting oxides," J. Mater. Sci. Lett. 11, 263-265 (1992).
    [CrossRef]

2002 (1)

H. El Rhaleb, E. Benamar, M. Rami, J. P. Roger, A. Hakam, and A. Ennaoui, "Spectroscopic ellipsometry studies of index profile of indium tin oxide films prepared by spray pyrolysis," Appl. Surf. Sci. 201, 138-145 (2002).
[CrossRef]

1998 (2)

R. A. Synowicki, "Spectroscopic ellipsometry characterization of indium tin oxide film microstructure and optical constants," Thin Solid Films 313-314, 394-397 (1998).
[CrossRef]

S. Laux, N. Kaiser, A. Zöller, R. Götzelmann, H. Lauth, and H. Bernitzki, "Room-temperaure deposition of indium tin oxide thin films with plasma ion-assisted evaporation," Thin Solid Films 335, 1-5 (1998).
[CrossRef]

1996 (2)

F. Hanus, A. Jardin, and L. D. Laude, "Pulsed laser deposition of high quality ITO films," Appl. Surf. Sci. 96-98, 807-810 (1996).
[CrossRef]

C. Coutal, A. Azéma, and J.-C. Roustan, "Fabrication and characterization of ITO thin films deposited by excimer laser evaporation," Thin Solid Films 288, 248-253 (1996).
[CrossRef]

1994 (1)

Wen-Fa Wu and Bi-Shiou Chiou, "Properties of radio-frequency magnetron sputtered ITO films without in-situ substrate heating and post-deposition annealing," Thin Solid Films 247, 201-207 (1994).
[CrossRef]

1992 (2)

Y. Shigesato, S. Takaki, and T. Haranoh, "Electrical and structural properties of low resistivity tin-doped indium oxide films," J. Appl. Phys. 71, 3356-3364 (1992).
[CrossRef]

J. R. Bellingham, W. A. Phillips, and C. J. Adkins, "Intrinsic performance limits in transparent conducting oxides," J. Mater. Sci. Lett. 11, 263-265 (1992).
[CrossRef]

1990 (1)

T. Nagatomo, Y. Maruta, and O. Omoto, "Electrical and optical properties of vacuum-evaporated indium-tin oxide films with high electron mobility," Thin Solid Films 192, 17-25 (1990).
[CrossRef]

1986 (1)

I. Hamberg and C. G. Granqvist, "Evaporated Sn-doped In2O3 films: basic optical properties and applications to energy-efficient windows," J. Appl. Phys. 60, R123-R159 (1986).
[CrossRef]

1983 (1)

Tze-Chiang Chen, Tso-ping Ma, R. C. Barker, and W. Hasan, "Properties and applications of infrared transparent and electrically conductive In2O3 thin film," Proc. SPIE 430, 270-273 (1983).

1981 (1)

J. C. C. Fan, "Sputtered films for wavelength-selective applications," Thin Solid Films 80, 125-136 (1981).
[CrossRef]

1979 (1)

J. C. C. Fan, "Preparation of Sn-doped In2O3 (ITO) films at low deposition temperatures by ion-beam sputtering," Appl. Phys. Lett. 34, 515-517 (1979).
[CrossRef]

1975 (1)

J. C. C. Fan and F. J. Bachner, "Properties of Sn-doped In2O3 films prepared by RF sputtering," J. Electrochem. Soc. 122, 1719-1725 (1975).
[CrossRef]

1958 (2)

L. J. van der Pauw, "A method of measuring specific resistivitiy and Hall effect of discs of arbitrary shape," Philips Res. Rep. 13, 1-9 (1958).

F. M. Smits, "Measurement of Sheet Resistivities with the Four Point Probe," Bell Syst. Tech. J. 711-718 (May 1958).

Appl. Phys. Lett. (1)

J. C. C. Fan, "Preparation of Sn-doped In2O3 (ITO) films at low deposition temperatures by ion-beam sputtering," Appl. Phys. Lett. 34, 515-517 (1979).
[CrossRef]

Appl. Surf. Sci. (2)

F. Hanus, A. Jardin, and L. D. Laude, "Pulsed laser deposition of high quality ITO films," Appl. Surf. Sci. 96-98, 807-810 (1996).
[CrossRef]

H. El Rhaleb, E. Benamar, M. Rami, J. P. Roger, A. Hakam, and A. Ennaoui, "Spectroscopic ellipsometry studies of index profile of indium tin oxide films prepared by spray pyrolysis," Appl. Surf. Sci. 201, 138-145 (2002).
[CrossRef]

Bell Syst. Tech. J. (1)

F. M. Smits, "Measurement of Sheet Resistivities with the Four Point Probe," Bell Syst. Tech. J. 711-718 (May 1958).

J. Appl. Phys. (2)

I. Hamberg and C. G. Granqvist, "Evaporated Sn-doped In2O3 films: basic optical properties and applications to energy-efficient windows," J. Appl. Phys. 60, R123-R159 (1986).
[CrossRef]

Y. Shigesato, S. Takaki, and T. Haranoh, "Electrical and structural properties of low resistivity tin-doped indium oxide films," J. Appl. Phys. 71, 3356-3364 (1992).
[CrossRef]

J. Electrochem. Soc. (1)

J. C. C. Fan and F. J. Bachner, "Properties of Sn-doped In2O3 films prepared by RF sputtering," J. Electrochem. Soc. 122, 1719-1725 (1975).
[CrossRef]

J. Mater. Sci. Lett. (1)

J. R. Bellingham, W. A. Phillips, and C. J. Adkins, "Intrinsic performance limits in transparent conducting oxides," J. Mater. Sci. Lett. 11, 263-265 (1992).
[CrossRef]

Philips Res. Rep. (1)

L. J. van der Pauw, "A method of measuring specific resistivitiy and Hall effect of discs of arbitrary shape," Philips Res. Rep. 13, 1-9 (1958).

Proc. SPIE (1)

Tze-Chiang Chen, Tso-ping Ma, R. C. Barker, and W. Hasan, "Properties and applications of infrared transparent and electrically conductive In2O3 thin film," Proc. SPIE 430, 270-273 (1983).

Thin Solid Films (6)

Wen-Fa Wu and Bi-Shiou Chiou, "Properties of radio-frequency magnetron sputtered ITO films without in-situ substrate heating and post-deposition annealing," Thin Solid Films 247, 201-207 (1994).
[CrossRef]

J. C. C. Fan, "Sputtered films for wavelength-selective applications," Thin Solid Films 80, 125-136 (1981).
[CrossRef]

C. Coutal, A. Azéma, and J.-C. Roustan, "Fabrication and characterization of ITO thin films deposited by excimer laser evaporation," Thin Solid Films 288, 248-253 (1996).
[CrossRef]

R. A. Synowicki, "Spectroscopic ellipsometry characterization of indium tin oxide film microstructure and optical constants," Thin Solid Films 313-314, 394-397 (1998).
[CrossRef]

S. Laux, N. Kaiser, A. Zöller, R. Götzelmann, H. Lauth, and H. Bernitzki, "Room-temperaure deposition of indium tin oxide thin films with plasma ion-assisted evaporation," Thin Solid Films 335, 1-5 (1998).
[CrossRef]

T. Nagatomo, Y. Maruta, and O. Omoto, "Electrical and optical properties of vacuum-evaporated indium-tin oxide films with high electron mobility," Thin Solid Films 192, 17-25 (1990).
[CrossRef]

Other (7)

S. Vigneron, X. Castel, G. Legeay, and J. Pinel, "Propriétés des couches minces d'ITO: influence de la proportion d'oxygène," in 8èmes Journées de Caractérisation Microondes et Matériaux, La Rochelle, France, (2004), paper G3.

C. Kittel, Introduction to Solid State Physics, 7th ed. (Wiley, 1996).

C. F. Bohren and D. R. Huffman, "Classical Theories of Optical Constants," in Absorption and Scattering of Light by Small Particles (Wiley, 1983).

R. E. Hummel, Electronic Properties of Materials (Springer Verlag, 1992).

CS Developpements, 1 rue Madeleine Crenon, F-92330 Sceaux (France). E-mail: csurfdvt@aol.com.

W. L. Wolfe and G. J. Zissis, The Infrared Handbook (Infrared Information Analysis Center, Environmental Research Institute of Michigan, 1989).

Rohm and Haas Company Advanced Materials, 185 New Boston Street, Woburn, MA 01801.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (10)

Fig. 1
Fig. 1

Measured spectral transmittance, reflectance and absorptance for an ITO layer on BK7 substrate. ITO layer: 280 nm thickness, 6.8 Ω / sq sheet resistivity.

Fig. 2
Fig. 2

Measured and simulated transmittance and reflectance for the ITO layer shown in Fig. 1. Drude model has been used for fitting and simulations (optical and electrical Drude parameters given in Table 2).

Fig. 3
Fig. 3

(a) Real and (b) imaginary parts of the refractive index for the ITO layer on BK7 shown in Fig. 1, calculated by the Drude model (optical an electrical Drude parameters, given in Table 2).

Fig. 4
Fig. 4

Measured and simulated transmittance, reflectance and absorptance for an ITO layer (16 nm thickness, 205 Ω / sq sheet resistivity) on magnesium fluoride substrate. The electrical Drude parameters (from DC measurements) have been used for this simulation (given in Table 2). Substrate transmission has been added for comparison.

Fig. 5
Fig. 5

(a) Real and (b) imaginary parts of the refractive index for the ITO layer on MgF2 shown in Fig. 4, calculated by the Drude model (DC Drude parameters, given in Table 2).

Fig. 6
Fig. 6

Measured and simulated transmittance and reflectance for an ITO layer on a small sapphire substrate. ITO layer: 17.4   nm thickness, 318 Ω / sq sheet resistivity. Drude model has been used for fitting and simulations (optical and electrical Drude parameters given in Table 2). Substrate transmission has been added for comparison.

Fig. 7
Fig. 7

(a) Real and (b) imaginary parts of the refractive index for the ITO layer on sapphire shown in Fig. 6, calculated by the Drude model (optical and electrical Drude parameters, given in Table 2).

Fig. 8
Fig. 8

Measured transmittance, reflectance, and absorptance for an ITO layer on a 100   mm diameter, 5   mm thickness sapphire substrate. Drude model has been used for transmittance and reflectance simulations, by taking the optical Drude parameters of the layer shown in Fig. 6, but 20.4 nm thickness, 271 Ω / sq sheet resistivity. Substrate transmission has been added for comparison.

Fig. 9
Fig. 9

Measured and simulated spectra for an ITO layer on zinc sulfide substrate. ITO layer: 23.3   nm thickness, 180 Ω / sq sheet resistivity. The optical and electrical Drude parameters have been used for simulation (given in Table 2). Substrate transmission has been added for comparison.

Fig. 10
Fig. 10

(a) Real and (b) imaginary parts of the refractive index for the ITO layer on ZnS shown in Fig. 9, calculated by the Drude model (optical and electrical Drude parameters, given in Table 2).

Tables (2)

Tables Icon

Table 1 Methodology: Direct and Inverse Simulations

Tables Icon

Table 2 Data for All ITO Films. Thickness and Electrical Measurements are Presented, as well as Results Issued from Fitting the Optical Measurements by the Drude Model (“Optical Drude Parameters”). The Effect of Experimental Uncertainties on Final Values is also Shown, Either Direct (Thickness and Electrical Measurements) or Indirect (Via Fitting of Measured Optical Spectra by Inverse Simulation)

Equations (6)

Equations on this page are rendered with MathJax. Learn more.

ε ( ω ) = ε ω N 2 ω 2 + γ 2 ,
ε ( ω ) = γ ω ω N 2 ( ω 2 + γ 2 ) ,
ω N 2 n e q 2 ε 0 m e f f ,
ω p 2 = ω N 2 ε γ 2 .
μ = q τ m e f f .
ρ = 1 n e q μ .

Metrics