Successive Ionic Layer Absorption And Reaction Research Articles

Effect of [Cu]/[In] ratio on properties of CuInS2 thin films prepared by successive ionic layer absorption and reaction method

Abstract CuInS 2 ternary films were prepared by a soft solution processing, i.e. successive ionic layer absorption and reaction (SILAR) method. The films were deposited on glass substrates at room temperature and heat-treated under Ar atmosphere at 500 °C for 1 h. CuCl 2 and InCl 3 mixed solutions with different ionic ratios ([Cu]/[In]) were used as cation precursor and Na 2 S as the anion precursor. The effect of the [Cu]/[In] ratio in precursor solution on the structural, chemical stoichiometry, topographical, optical and electrical properties of CuInS 2 thin films was investigated. XPS results demonstrated that stoichiometric CuInS 2 film can be obtained by adjusting [Cu]/[In] ratios in solution. Chalcopyrite structure of the film was confirmed by XRD analysis. The near stoichiometric CuInS 2 film has the optical band gap E g of 1.45 and resistivity decreased with increase of [Cu]/[In] ratios.