纳秒激光刻蚀玻璃基质铬薄膜直写微光栅结构

Fabrication of Micro-grating Structures by Nanosecond Laser Ablation of Chrome Film on Glass Substrate

利用波长为351nm的半导体泵浦全固态脉冲激光器,采用双光束干涉方法,对蒸镀在石英玻璃衬底上的铬薄膜直接刻蚀形成微光栅结构的方法进行了实验研究.通过实验,分析了激光能量和脉冲数与微光栅结构槽形和一级衍射效率之间的关系.利用光学显微镜和原子力显微镜检测分析光栅槽形,测得槽深为253nm的最佳微光栅结构,并测得其在波长为532nm的激光的一级衍射效率为6.5%.结果表明:在激光能量为1150μJ时,适当增加曝光脉冲数有利于提高制备光栅的槽深和一级衍射效率.

A method of etching micro-grating structures （MGSs） by ablating chrome film on glass was investigated,which was used the interference laser of 351 nm diode-pumped solid-state laser （DPSSL） pulses. Through changing the experimental parameters such as laser power, number of laser pulses, the influences of these parameters on the depth of grooves and diffraction efficiency of MGSs were analyzed. Measured by conventional optical microscopy and atomic force microscopy （AFM）,the highest depth of MGSs is 1.01 μm. The first-order diffraction efficiency of the MGSs was measured using 532 nm laser,and the highest of witch was 6.5 %. The experimental results show that increasing the number of laser pulses properly in prpper laser energy,the depth of grooves and diffraction efficiency are increased.