Highly conducting indium tin oxide films grown by ultraviolet-assisted pulsed laser deposition at low temperatures

Indium tin oxide films grown by conventional and ultraviolet-assisted pulsed laser deposition technique (PLD and UVPLD) on Si and Corning glass were analyzed by grazing and symmetric incidence X-ray diffraction. Films deposited at substrate temperatures up to 70 degreesC were amorphous, while films deposited at temperatures of 120 degreesC and higher showed good crystallinity, with a (2 2 2) texture. The diffraction peaks were split indicating that the films contained a two-layer structure. X-ray reflectivity studies showed that the film surface roughness was below 0.5 nm and their density approximately 7.20 g/cm(3). Spectroscopic ellipsometry measurements indicated that the films were highly transparent, while X-ray photoelectron spectroscopy investigations showed homogeneous bulk chemical composition and a very small Sn enrichment in the surface region. The carrier mobility was rather high for films deposited at 40 and 70 degreesC and then decreased with the increase of the substrate temperature, because the onset of crystallization at such low temperatures produces a defective structure. (C) 2003 Elsevier B.V. All rights reserved.