Physical properties of SnO2: Co thin films prepared by chemical spray pyrolysis


Areej Adnan Hateef1, Marwa Abdul Muhsien Hassan2,Najim A. Sumoom1, Sabah Jameel1

1 Iraqi Ministry of Sciences and Technology, 2  College of science, Al- Mustansiriyah University



Abstract
     In this research, Co-doped SnO2 thin films were prepared by chemical spray pyrolysis technique using SnCl4.5H2O and CoCl2.6H2O, with impurity percentage are (0%-3%-6%-9%) on glass substrates preheated at (450oC) with spray rate 5sec./1min, and thickness (400nm). The investigation of (XRD) indicates that the (SnO2) films are polycrystalline type of (tetragonal), the optical properties and band gap energy was observed  and it`s found varied from (3.361-2.855 eV) when increasing in percentage  impurity the energy band gap decreased. The Hall coefficient, concentration and mobility of charge carriers of SnO2:Co films studied, and their results observed that the increase in impurity of cobalt caused increase in electrical properties generally. 
 
Keywords: thin films, SnO2, chemical spray pyrolysis, cobalt.

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