Transparent conductors—A status review

The surface and materials science of tin oxide

We review work on In2O3:Sn films prepared by reactive e‐beam evaporation of In2O3 with up to 9 mol % SnO2 onto heated glass. These films have excellent spectrally selective properties when the deposition rate is ∼0.2 nm/s, the substrate temperature is ≳150 °C, and the oxygen pressure is ∼5×10−4 Torr. Optimized coatings have crystallite dimensions ≳50 nm and a C‐type rare‐earth oxide structure. We cover electromagnetic properties as recorded by spectrophotometry in the 0.2–50‐μm range, by X‐band microwave reflectance, and by dc electrical measurements. Hall‐effect data are included. An increase of the Sn content is shown to have several important effects: the semiconductor band gap is shifted towards the ultraviolet, the luminous transmittance remains high, the infrared reflectance increases to a high value beyond a certain wavelength which shifts towards the visible, phonon‐induced infrared absorption bands vanish, the microwave reflectance goes up, and the dc resisitivity drops to ∼2×10−4 Ω cm. The corre...

Evaporated Sn‐doped In2O3 films: Basic optical properties and applications to energy‐efficient windows

SnO2: A comprehensive review on structures and gas sensors

Band-gap determination from diffuse reflectance measurements of semiconductor films, and application to photoelectrochemical water-splitting

Tin oxide films have been prepared on glass substrates by spray pyrolysis technique. The electrical and optical properties of undoped and antimony‐doped tin oxide films have been studied. The temperature dependence of electron mobility has been analyzed to establish the electron conduction mechanism. Optical properties near the plasma edge have been analyzed using Drude’s theory. The dependence of effective mass on carrier concentration has been explained on the basis of nonparabolicity of the conduction band. The shift in the Fermi energy, calculated on the basis of energy dependent effective mass, is consistent with the measured shift in the absorption edge.

Electrical and optical properties of undoped and antimony‐doped tin oxide films

This paper presents the structural, electrical, and optical properties of F‐ and (Sb+F)‐doped tin oxide films prepared by spray pyrolysis technique. Resistivity as low as 5.5×10−4 Ω cm with high optical transmission (≳80%) and high infrared reflection (∼90%) have been obtained in F‐doped tin oxide films. The figure of merit ΦTC = T10/Rsh (52.6×10−3Ω−1 at 0.65μm) of these films is the highest amongst the results reported on doped tin oxide films. The variation of mobility with doping concentration has been analyzed to understand the electron–conduction mechanism. The Drude theory has been used to explain the optical properties near the plasma edge.

Electrical and optical properties of tin oxide films doped with F and (Sb+F)

Dopant effects in sprayed tin oxide films

Annealing characteristics of tin oxide films prepared by spray pyrolysis

Transparent and conducting films of pure and antimony doped tin oxide have been prepared by spray technique. An optimum value of 18 ohm per unit area sheet resistance with 82% optical transmission has been obtained. Detailed studies of electrical and optical properties of these films have been made as a function of antimony concentration. The films behave like degenerate semiconductors. The low value of effective mass for undoped tin oxide films indicates a distortion in Fermi surface. The effective mass was found to increase with antimony concentration up to 6 mole % and the Fermi level shifted towards the conduction band. These films have been used as base contact layers in the special inverted configuration of sprayed Cu 2 S-CdS solar cells.

E. Shanthi

Papers

Electrical and optical properties of undoped and antimony‐doped tin oxide films

Electrical and optical properties of tin oxide films doped with F and (Sb+F)

Dopant effects in sprayed tin oxide films

Annealing characteristics of tin oxide films prepared by spray pyrolysis

Transparent conducting coatings for solar cells