液相电化学沉积法制备高氮含量CNx薄膜及性能的研究

采用液相电化学沉积法,以二氰二胺的丙酮溶液为沉积液,以镀有ITO(铟锡氧化膜)的导电玻璃为衬底制备了CNx薄膜.初步探讨了沉积温度和沉积电压对薄膜中氮含量的影响.通过XPS、FTIR光谱、SEM和US-Vis光谱对得到的CNx薄膜的化学结合状态、结构形貌和光学性质进行了表征,并用高电阻仪对薄膜的绝缘性进行了分析.XPS结果表明,CNx薄膜中碳氮主要以单键连接,sp3杂化的C—N键占85%.在IR光谱中,仅出现了C—N键和CN双键的吸收峰.SEM图谱显示CNx薄膜呈颗粒状,粒径平均为80nm左右.在水浴加热条件下沉积的CNx薄膜在200～300nm近紫外区为非线性吸收.薄膜的电阻率随氮含量的增加而增大,测量值在1012～1016Ω·cm之间.

Research on Preparation and Properties of CNx Thin Films with High Nitrogen Content by Electrodeposition in Liquid Phase

CNx thin films with a high nitrogen content were prepared on ITO conductive glass substrates by cathode electrodeposition, using dicyandiamide(C2H4N4) in acetone as the precursors. The surface morphologies of CNx thin films were observed by thermal field emission scanning electron microscopy(SEM). The size of CNx got a nanometer level, with about 80 nm minimum size. The N/C atomic ratio and bond state in the films were studied by X-ray photoelectron spectroscopy(XPS). The maximum value of the N/C atomic ratio was 1.08. Carbon and nitrogen existed mainly in the form of C-N bond, with little CN bond. Fourier transform infrared(FTIR) spectroscopy supports the existence of C-N covalent bond. Through the UV-Vis absorption phenomenon, the ultraviolet radiation(200-280 nm) could be transmitted. The electrical resistivities of the films were in the range of 1012-1016 Ω·cm.