Light induced adsorption of Si nano-composites in LiF crystals at 157 nm

Si nano-composites were precipitated on LiF crystals following ablation from Si targets with laser light at 157 nm. The LiF/Si interface was analyzed with scanning electron microscopy, atomic force microscopy and energy dispersive X-ray microanalysis. It was found that Si composites were strongly attached to LiF ionic sites to form inhomogeneous structures consisted of small isotropic crystals 0.1–1 mm long, rich in Si and fluorine, which eventually further agglomerate to form larger structures. The thickness of the LiF/Si interface was increased from 50 nm to 2 mm following laser irradiation at 157 nm, due to accelerated adsorption of Si in the LiF interface by VUV light.