Abstract: The chemical etching properties of micro-structure in three typical glasses modified with femtose-cond laser were studied. The micro-structure changes before and after etching were observed. The depen-dences of etching rate on the pulse energy and etching duration were revealed. The mechanisms of glass modifying-chemical etching were discussed. The results show that the femtosecond laser modified tellurite and lead silicate glass have no chemical selective etching, but the selective etching rate of silica glass is higher than 40. The character of chemical selective etching of femtosecond laser modified glass largely depends on the matrix local structures, the glass with a lager molecule volume has no properties of chemical selective etching, such as tellurite and lead silicate glass.

Key words: Femtosecond laser, Chemical etching, Micro-structure of glasses