聚酰亚胺基碳膜形成过程中表面结构的XPS研究

AN XPS STUDY OF THE SURFACE STRUCTURE OF POLYIMIDE-BASED CARBON FILM DURING THE RORMATION

用Ｘ射线光电子能谱（ＸＰＳ）分析方法考察了聚酰亚胺薄膜样品在不同热解阶段的元素组成、相对含量、表面官能团类型所发生的变化，并用曲线拟合分峰技术对Ｃ￣（１Ｓ）谱进行了数学处理。结果表明，碳、氮和氧是该样品的基本元素；样品表面的碳大部分为类石墨碳，Ｃ—Ｃ和Ｃ—Ｈ是其主要的基团；氧元素主要与碳连接形成了Ｃ—Ｏ基和Ｃ＝Ｏ基的两种含氧基团；表面的氮则是以Ｃ—Ｎ基的形式存在。根据各元素单扫描的峰面积所计算出的碳、氮和氧的相对含量，表明试样在整个热解过程中随热解温度的上升，碳元素含量自８２．８９％增长到９０．４１％；氨含量自３．２７％下降到１．５３％；氧含量的自１３．８４％下降到８．０６％。由整个ＸＰＳ的测量结果提出了所形成的聚酰亚胺基碳膜的表面结构可认为是一个较大的缩合杂环网状结构。

The changes of the elemental composition,the relative content and the types of surface groups for the sample of polyimide film at the different stages of pyrolysis were studied by using X-ray photoelection spectroscopy analytical method,and the carbon 1S peaks have been measured mathematically by means of the curve fitting technique.The results show that carbon,nitrogen and oxygen are three basic elements in sample.Most of carbon atoms on the surface of sample are in the form of graphite-like carbon,the C C group and the C H group are two of the most important groups in sample.Oxygen atoms are mainly in the forms of the C O group and the C=O group. Nitrogen atoms are mainly in the form of the C N groups.On the basis of the relative contents of carbon, nitrogen and oxygen calculated through the areas of the peak for simple scan of the each element show that as the pyrolytic temperature raised the content of carbon element was increased from 82.8% up to 90.41%,the nitrogen content decreased from 3.27% up to 1.53% and the oxygen content decreased from 13.84% dropdown to 8.06% in sample surface.From the XPS measurement it was suggested that the surface structure of Polyimide-based carbon film was thought to be a larger and denser heterocyclic network.