Electrical, optical, and structural characterization of arsenic–tin oxidized transparent conducting films

A comprehensive structural, optical, electrical, and optoelectronic study of arsenic-doped SnO2 was conducted. Several arsenic-doped SnO2 thin films with different arsenic content have been prepared on glass and silicon substrates by a vacuum thermal evaporation technique. The structural, electrical and optical study show that some of As5+ ions occupied locations in interstitial positions of SnO2 lattice. The prepared oxidized pure tin film is found to be consisting of orthorhombic and tetragonal SnO2 structure. The optical properties show that arsenic-doped SnO2 films are good transparent oxides. The bandgap of arsenic-doped SnO2 varies with arsenic content following the Moss–Burstein rule. The electrical behaviors show that the prepared arsenic-doped SnO2 films are degenerate semiconductors and might transform into insulators with increasing arsenic doping level. The electrical properties (resistivity, mobility, and carrier concentration) vary depending on the arsenic doping level. The SnO2 film doped with wt. 0.6% arsenic shows utmost dc electrical conductivity parameters: resistivity of 4.6 10 2 X cm, mobility of 6.0 cm2/V s, and carrier concentration of 2.25 1019 cm 3. From transparent-conducting-oxide (TCO) point of view, low arsenic concentration (less that 1%) is effective for SnO2 donor doping but not emulate doping with other dopant like Sb. 2011 Elsevier Ltd. All rights reserved