Laser firing of transparent conducting SnO2 sol—gel coatings

doi:10.1016/S0022-3093(97)00166-X

Journal of Non-Crystalline Solids

Volume 218, 2 September 1997, Pages 242-246

https://doi.org/10.1016/S0022-3093(97)00166-X Get rights and content

Abstract

Sb doped sol—gel SnO₂ films were prepared from 0.5 M alcoholic solution of SnCl₂(OAc)₂ doped with 5 mol% SbCl₃ and deposited via a dip coating process on fused silica substrates. The coatings have been fired by CO₂ laser irradiation by means of a 700 W cw CO₂ laser using a fast scan mode in which the laser beam is scanned by a high speed rotating polygon scanner (ω_max = 8800 rpm) in one direction and the sample is moved perpendicularly at a speed up to 250 mm/s. Areas can be densified at a typical rate of ≈ 12 cm²/s. The properties of the coatings have been measured by several methods: their sheet resistance, R□, has been measured using a four-probe technique, the structure of the coatings has been determined by X-ray diffraction at grazing incidence, their thickness by a surface profiler and their morphology by transmission electron microscopy. The thickness of the coatings, the crystallite size and the sheet resistance are determined by thermal driven processes. The coatings are made of dense aggregates of spherical shaped crystallites. The smallest resistivity obtained for a 100 nm thick coating is ϱ = 6 × 10⁻³ ω cm a value that is three times lower than that obtained with conventionally heat treated samples.

References (8)

H. Dislich
H. Schröder
D.J. Taylor et al.
G. Gasparro

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