Square-shape distribution of ZnO crystals in glass by using a spatial light modulator

• Square-shape distribution of ZnO crystals in glass was achieved.
• The elemental distributions of Zn2 + agree well with square-shape distribution of ZnO crystals.
• This method may provide a new way for spatial control of fs laser induced crystallization.

We report on square-shape distribution of ZnO crystals in glass by simultaneous femtosecond laser irradiation at multiple spots with the application of a spatial light modulator. Raman spectra and Raman mapping were used to characterize the formation of ZnO crystals and distribution of ZnO crystals, respectively. The shapes of the laser-modified region and the distribution of ZnO crystals were compared between the cases of one spot irradiation and multiple spot irradiation. The elemental distributions of the laser-modified region were investigated by an Electron Probe Microanalyzer.