摘要
ZnO_(1-x)S_(x) thin films modified by sulfur doping were prepared on glass substrates by chemical bath deposition(CBD) for studying the effect of thiourea concentration on the thin film properties. The obtained ZnO_(1-x)S_(x) thin films were characterized by scanning electron microscopy(SEM), which shows the surfaces of ZnO_(1-x)S_(x) thin films deposited under the thiourea concentration of 0.14 M are more compact. X-ray diffraction(XRD) measurement shows that the ZnO_(1-x)S_(x) thin films with hexagonal crystal structure had strong diffraction peaks and better crystallinity. The optical transmittance of the ZnO_(1-x)S_(x) thin films with 0.14 M thiourea concentration is above 80% in the wavelength range of 300-900 nm. According to the measurement results from spectrophotometer, the ZnO_(1-x)S_(x) band gap energy value Eg varies nonlinearly with different S/(S+O) ratio x, and increases with the increase of x. There is a band gap value of 2.97 eV in the ZnO_(1-x)S_(x) thin films deposited under 0.14 M thiourea concentration. Therefore, the thin films have better structural, optical and electric properties, and are more suitable for the buffer layers of copper indium gallium selenide(CIGS) thin film solar cells.
基金
supported by the Natural Science Foundation of Tianjin (No.18JCYBJC95400)。