Structural and photoluminescence properties of single crystalline SnO2:In films deposited on α-Al2O3 (0 0 0 1) by MOCVD

Indium-doped tin oxide (SnO2:In) films have been prepared on α-Al2O3 (0 0 0 1) substrates by the metalorganic chemical vapor deposition (MOCVD) method. The structural and photoluminescence (PL) properties of the SnO2:In films were investigated. The prepared samples were epitaxial single crystalline films having rutile structure of pure SnO2 with the best single crystalline structure obtained at 4% (atomic ratio) of In concentration. A single ultra-violet (UV) PL peak near 339 nm was observed at room temperature (RT) for the 4% In-doped film. At a temperature of 14 K, another narrow PL peak located at 369 nm and a broad feeble peak near 493 nm were also observed. The corresponding PL mechanisms were investigated.