| Summary: | 碩士 === 國立成功大學 === 化學系 === 103 === We successfully fabricated AgInSe2 and (Ag,Cu)InSe2 thin films by triethanolamine complexing agent using electrodeposition method. The parameters include：deposition potential and time in electrodeposition, concentration of TEA, pH value, concentration of silver ions and copper ions, annealing temperature. For the first study, AgInSe2 have been prepared to identify concentrations of silver ion could be obtained composition of product. With lower reduction potential was easy to form a binary compound Ag2Se. The main preferred orientations of AgInSe2 is (112) as the applied potential increased to -1.0 V, this result is consistent to that from XRD. The surface morphology of AgInSe2 was observed by SEM, thin films revealed sphere shape with lower reduction potential and uniformly distributed dendrimer structures with higher reduction potential. Finally, the absorption coefficient of AgInSe2 were analyzed by using UV/VIS/NIR spectra, this work obtained AgInSe2 thin films with high absorption coefficient (above about 104 cm-1) after annealed. This results showed an optimum deposition condition: 7 mM AgNO3 + 10 mM In2(SO4)3．9H2O + 40 mM SeO2 + 0.2 M TEA, electrodeposition time was 20 min, annealing temperature at 280 °C, the value of band gap was 1.23 eV.
For the second study, (Ag,Cu)InSe2 thin film was electrodeposited with various [Cu]/[Ag] to adjust composition wanted. When occupies of Ag were substituted after Cu were added to it, XRD analysis of AgInSe2 diffraction peak on (112) plane has disappeared instead of CuInSe2 diffraction peak on (112) plane. With concentrations of CuSO4．5H2O and the reduction potential increased that the diffraction peaks intensity became obviously stronger, and morphologies analysis of thin films were like to cauliflower structures. The absorption coefficient and band gap of (Ag,Cu) InSe2 thin films were less than AgInSe2.
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