Chemical Bath Depositon For Metal Chalcogenide Photoelectric Functional Thin Films

The present thesis aimed to explore a low-energy, environmental amiably synthesis route, Chemical Bath Deposition, for depositing metal chalcogenide photoelectric functional thin films, and characterize the structure, morphology and optical properties of obtained thin films.Recently, antiferromagnetic manganese sulphide (MnS) had been the focus of intense research due to its unique properties. MnS was a potential buffer/window materials for solar cell and was especially used in mixing with Zn and Cd to form (Zn, Mn)S and (Cd, Mn)S, which belonged to diluted magnetic semiconductor (DMS). In the present thesis, the crystalline y-MnS had been synthesized via chemical bath deposition at low temperatures. Through changing deposition parameters, the (002) oriented y-MnS films consisted of crystallite with improved structure were also obtained.On the base of experimental results, the chemical reactions and equilibriums likely to occur during the deposition processes were discussed. It was ascertained that the parameters had major influence on the films by determining the available free metal ion [M] and [chalcogenide] for the metal chalcognide formation, i.e., the degree to which the solubility limit is exceeded, either directly or indirectly.To study the optical properties of y-MnS films prepared at different deposition condition, the UV-VIS spectra of them were carried out by a UV-VIS-NIR spectrophotometer and the optical band gap of them were calculated by the transmission and reflection data. Among the optical band gap of all measured samples, the biggest one is 3.55eV and the smallest one is 3.07eV.In addition, the photoluminescence mechanics of y-MnS was discussed through analyzing the photoluminescence spectra measured at different temperatures. The photoluminescence of y-MnS was a unique local luminescence phenomenon and dependent on the interaction between the local magnon alignment and the local impurity-disturb.At last, the Hausmannite manganomanganic oxide (Mn3O4) thin films were deposited by chemical bath deposition and the affect of different deposition parameters on the films was also discussed. At the same time, we also noticed the properties of the as-grown powder produced during the deposition. Following theobtained experimental results, the reactions likely to occur during the process were proposed. And then, the optical properties of Mn3O4 films were studied according to UV-VIS spectrum.