The dependence of the electrical and optical properties of reactively evaporated indium tin oxide films on substrate temperature and tin concentration has been studied. Films of resistivity as low as 3 x 10-4 Ω cm and high visible transparency of about 91% have been obtained at higher deposition temperatures (∼300 °C) for tin concentrations of 10-1 5 wt% in the source alloy. Hall mobility in the films has been found to decrease with the addition of tin and increase with deposition temperature. An observed increase in carrier density with substrate temperature has been viewed as being due to the possibility that higher deposition temperature favours the incorporation of tin as Sn4- in the films. In the optical band-gap calculation the effect of collision broadening, which is typical for a degenerate semiconductor, has been included and found to be significant. © 1989 IOP Publishing Ltd.

A Subrahmanyam

Department Of Physics

COLLISION BROADENING

Hall Mobility

Indium tin oxide

Optical band gap

Band structure

Electric properties

Optical properties

Semiconducting indium compounds

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

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IIT Madras

Electrical and optical properties of reactively evaporated indium tin oxide (ITO) films-dependence on substrate temperature and tin concentration

Journal of Physics D: Applied Physics

Silver-doped indium oxide thin films have been prepared on glass and quartz substrates at room temperature (300 K) by a reactive dc magnetron sputtering technique using an alloy target of pure indium and silver (80 : 20 at. %). During sputtering, the oxygen flow rates are varied in the range 0.00-2.86 sccm keeping the magnetron power constant at 40 W. The resistivity of these films is in the range 100-10-3 Ωcm and they show a negative temperature coefficient of resistivity. The films exhibit p-type conductivity at an oxygen flow rate of 1.71 sccm. The work function of these silver-indium oxide films has been measured by a Kelvin probe technique. The refractive index of the films (at 632.8 nm) varies in the range 1.13-1.20. Silver doping in indium oxide narrows the band gap of indium oxide (3.75 eV).

Applied Physics A: Materials Science and Processing

Electrical and optical properties of reactive dc magnetron sputtered silver-doped indium oxide thin films: Role of oxygen

Tin oxide (SnO2) thin films are prepared on soda-lime glass substrates by spray pyrolysis using anhydrous and pentahydrate (SnCl4ṡ5H2O) tin chloride as starting material. X-ray diffraction data and the electrical and optical properties of these films as a function of substrate temperature (553-713 K) are reported. The growth rate of SnO2 films prepared from SnCl4ṡ5H2O is observed to be higher and the resistivity is lower than for films prepared from anhydrous SnCl4. © 1991.

Thin Solid Films

Physical properties of sprayed SnO2 films

Journal of the Electrochemical Society

Studies on Evaporated Indium Tin Oxide (ITO)/Silicon Junctions and an Estimation of ITO Work Function

In this paper we present the results of our studies on the Schottky barrier at theindium tin oxide (ITO) -n-GaAs interface and the effect of an arsenic-deficient GaAs surface on the barrier height. The ITO/n-GaAs junctions were prepared by depositing ITO (by a reactive thermal evaporation technique) on as-cleaned and heat-treated GaAs substrates of 〈100〉 orientation. The heat treatment of GaAs gave rise to an arsenic-deficient surface. The current-voltage characteristics of the Schottky diodes exhibit two current transport mechanisms: depletion region recombination and thermionic emission. The height of the Schottky barrier at the interface between ITO and as-cleaned GaAs is 0.83 ± 0.02 eV and that at the interface of ITO and heat-treated GaAs is 1.05 ± 0.02 eV as evaluated using I-V and C-V methods. The results are in accordance with the defect models for Schottky barrier formation. The junctions having an enhanced barrier exhibit a photoconversion efficiency of 7.75%, the highest for any ITO/GaAs junctions reported so far. © 1990 Elsevier Sequoia S.A.

Schottky barrier at the indium tin oxide -n-GaAs interface: Effect of surface arsenic deficiency

The dependence of electrical and optical properties of SnO2 films, prepared using the spray pyrolysis technique, on the substrate temperature and substrate-nozzle distance was studied. A 0.05 cm diameter spray nozzle was employed ( 1 4 JAU, Spraying Systems Inc., U.S.A.). Films of about 10-3 Ω cm resistivity and high visible transparency of about 90% were obtained at a substrate temperature of 400°C and a substrate-nozzle distance of 30 cm. It has been observed that substrate-nozzle distance plays an important role in the reaction kinetics of SnO2 films. At a substrate-nozzle distance greater than 30 cm, the homogeneous reaction enhances and hence impedes the growth rate, resulting in inferior electrical and optical properties of the films. © 1990.

Journal	Journal of Physics D: Applied Physics
ISSN	00223727
Open Access	No