为了研究准分子激光刻蚀聚甲基丙烯酸甲酯(PMMA)的内在机理，将波长为248nm的KrF准分子激光垂直照射到PMMA材料表面，改变激光能量和脉冲数目，在大气背景下进行实验，照射后样品的表面形貌及化学结构用扫描电子显微镜(SEM)、3维形貌分析仪、X射线光电子能谱(XPS)等手段进行分析。 SEM测试表明,在刻蚀区域出现孔状结构，说明刻蚀过程中有气体成分产生。XPS测试表明,激光照射后C1s峰的强度减弱而O1s峰增强，据此推测PMMA侧链上的甲基被刻蚀掉且空气中的O2参与了反应。另外还研究了激光能量和脉冲数目对刻蚀率和表面粗糙度的影响。结果表明，随着激光能量和脉冲数目增加，刻蚀率和粗糙度并不是一直呈现递增的趋势。

In order to research the internal mechanism of interaction between excimer laser and polymethylmethacrylate(PMMA ), the surface of PMMA was vertically irradiated by KrF excimer laser at wavelength of 248nm, and the experiment was completed in atmosphere through changing laser energy and pulse number. The treated PMMA was analyzed with many methods, for example scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS), etc. The results of SEM indicate that a lot of apertures can appear at the irradiated surface of PMMA. The phenomenon means that some gas is given out when excimer laser irradiates PMMA. The results of XPS show that peak intensity of C1s decreases but peak intensity of O1s increases, so the methyls of PMMA are etched and O2 in atmosphere attends the reaction. Besides, the research on the etching rate and the roughness indicates they do not always increase when laser energy and pulse number increase.