Preparation of Cu2O Thin Films by Electrochemical Deposition Method Using Different Copper Sources and Investigation of Their Properties

In this thesis, Cu2O semiconductor thin films were produced on ITO (Indium tin oxide) substrates using different copper precursor [Cu(CH3COO)2·H2O (copper (II) acetate), CuSO4·5H2O (copper (II) sulfate), Cu(NO3)2·3H2O (copper (II) nitrate), CuCl2·2H2O (copper (II) chloride)] using the electrochemical deposition (ECD) method at 60 oC. The structural, morphological, optical, and electrical properties of these thin films were analyzed in detail, and the obtained results were evaluated comparatively. XRD analyses determined that all films crystallized in the cuprite phase in the cubic crystal system and showed a strong preferential orientation in the (111) plane. In addition, the Cu2O thin films obtained with the copper sulfate precursor salt exhibited higher crystallization quality than those produced with other copper salts. FE-SEM images showed that the thin films generally had a regular morphology and homogeneous crystal distribution, and the most successful results in terms of morphological quality were obtained with copper sulfate salt.The basic optical parameters (%T, %R, A, Eg, n, k, ε1, ε2,) of the thin films were calculated using a UV-Vis spectrophotometer. The energy band gaps (Eg) of Cu2O thin films prepared with copper acetate, sulfate, nitrate, and chloride precursor salts were determined as 2,54 eV, 2,49 eV, 2,52 eV, and 2,59 eV, respectively. In AFM analysis, the lowest surface roughness values were observed in the Cu2O thin film prepared with copper sulfate salt (Ra: 2,49 nm; Rq: 3,08 nm).