采用Nd:YAG纳秒脉冲激光对单晶硅在空气中进行辐照, 研究了表面微结构在不同能量密度和扫描速度下的演化情况。扫描电子显微镜测量表明, 激光在相对较低能量密度下辐照硅表面诱导出鱼鳞状波纹结构, 激光能量密度相对较大时, 诱导出絮状多孔的不规则微结构。光致荧光谱(PL)表明, 激光扫描区域在710 nm附近有荧光发射。用氢氟酸腐蚀掉样品表面的SiOx后, 荧光峰的强度显著降低, 说明SiOx在光致发光增强上起重要作用。能量色散X射线谱(EDS)表明氧元素的含量随激光能量密度的增大而增加。研究表明：纳秒激光的能量密度和扫描速度对微结构形成起着决定性作用, 改变了硅材料表面微结构尺寸, 增大了光吸收面积；氧元素在光致发光增强上起重要作用, 微构造硅和SiOx对光致荧光的发射都有贡献。

The evolution of silicon surface microstructures irradiated by Nd: YAG nanosecond laser pulses in the air under different laser fluences and scanning speeds was studied. The scanning electron microscope (SEM) images show that corrugated structure and porous structure are formed on the silicon surfaces after laser pulse irradiation. The photoluminescence (PL) spectra indicate a peak of luminescence at 710 nm. After corroding the SiOx on the silicon surfaces with hydrofluoric acid, the intensity of the luminescence peak greatly reduces, which proves that SiOx plays an important role in photoluminescence enhancement. The energy dispersive X-ray spectrum (EDS) shows that the amount of oxygen incorporated into the silicon surfaces depends on the laser fluence. Oxygen element in silicon surfaces has an important impact on enhancing PL emission.