【摘要】 在室温真空条件下,用北京大学离子注入机提供的3 MeV Si⁺对厚度大约25μm的电绝缘聚酰亚胺（PI/Kapton）进行了表面改性,通过紫外可见光谱分析（UV/Visible）、傅立叶转换红外光谱分析（FTIR）及电性能测量,研究了不同离子注量(1×10¹²—1×10¹⁵cm^-2)下注入层中聚酰亚胺各官能团的化学降解及石墨化结构转变机制。红外结果表明,官能团随离子注入量的增加指数降解,并通过实验点的拟合给出了典型分子键的损伤截面。辐照后聚合物的导电性发生了巨大变化,在我们的实验中,聚酰亚胺的面电阻与未辐照样相比下降了近10个数量级,呈现出半导体的电特性。紫外光谱中吸收边缘从紫外到可见区的红移表明了光能隙的逐渐减小,这是由于芳香团尺寸的增加而引起的。更多还原

【Abstract】 The surface modification of polyimide films was carried out by 3MeV Si+ implantation under vacuum at room temperature and ions fluence ranging from 1 × 1012 to 1 × 1015 cm-2. The chemical degradation of function groups and the mechanism of the structure translation in the irradiated layer were investigated by Fourier Transform Infrared (FTIR), Ultraviolet/Visible (UV/Vis) spectroscopes and electrical behavior measurement. FTIR results show that the absorbance of typical function group decreases exponentially as a function of fluence. The damage cross section of typical bonds of PI was evaluated from the FTIR spectra. Irradiation dramatically enhances the electrical conductivity, and the sheet resistance in our experiment descends nearly 10 orders of magnitude compared with its intrinsic value. The red shifting of the absorption edge from UV to visible reveals the reduction of band gap which results from the increase of the cluster size.更多还原