Preparation And Performance Of Ce-depoed And Sb-doped SnO₂ Transparent And Conductive Thin Films

The SnO₂ transparent and conductive thin film which has the fine photoelectricity performance and widely been applied in each kind of photoelectric apparatus, is one kind of use extremely widespread special function thin film. Using metal salts SnCl₂·H₂O,SbCl₃ and Ce(NO₃)₃·6H₂O as precusors, thin films of Sb-doped and Ce-doped tin oxide has been deposited by the sol-gel method on glasses. The microstructure and surface morphology of SnO₂ thin films were investigated by XRD and SEM; The sheet resistance value of SnO₂ thin films were measured by the DSY-5 four probes resistances reflectoscope reflector; Besides, The average transmissibility in visible light of SnO₂ thin films were measured by the Ultraviolet-Visible Spectrophotometer. The influences of annealing temperature and dopant amount of Sb-doped and Ce-doped SnO₂ thin films were discussed. The results were showm as follows:(1) The SnO₂ crystals with Sb-doped and Ce-doped exist as tetragonal rutile structure, and higher temperature can benefit the crystallization of SnO₂ crystals. Sb-doped films with good crystallinity were grow with dopant amount of 15%～20% at the heat-treatment temperature of 500℃～550℃; and Ce-doped films with good crystallinity were grow with dopant amount of 1.0%～8.5% at the temperature of 500℃. But too high doping level (Sb＞20%,Ce＞1.5%) will do harm to the crystallization performance of the films.(2) The electrical behaviours of SnO₂ thin films with doping have been investigated. It shows that the heat treatment temperature and the dopant amount all have the important influence to the thin film electric conductivity, and SnO₂ films with suitable doping level have the best electrical conductivity. The sheet resistance can reach 239Ω/â–¡, after the films have been treated under 500℃, with Sb doping level 15%; and the sheet resistance can reach 51.4×10³Î©/â–¡, after the films have been treated under 500℃, with Ce doping level 1.0%. It can be see that the Sb doping SnO₂ thin film has a better electric conductivity.(3) The optical behaviours of SnO₂ thin films with doping have been investigated. Research indicates that the heat treatment temperature and the doping density all have the important influence to the SnO₂ thin film in the ultraviolet visible light wave band transmissibility, and the transmittance in visible light range of films with doping is decrease with the increase of the dopant amount when the heat treatment temperature is same, and the thin film average visible light transmissibility slightly has the increase with the heat treatment temperature enhances When the doping density is certain. The Ce doping thin film visible light transmissibility maximum value achieves 90% and the Sb doping thin film highest visible light transmissibility does not surpass 70%. It can be see that the Sb doping SnO₂ thin film has a better transparency。...