Patterned LiNbO3 thin film fabrication basing aqueous precursor and the study on pattern quality and film morphology

• Patterned LN film was fabricated basing an inexpensive aqueous precursor preparation route.
• Patterned LN film was fabricated in photolithography and laser-induced crystallization ways.
• Pattern quality is affected by gel solubility, laser scanning factors and substrate temperature.
• The temperature gradient to the pattern quality for laser-induced crystallization is emphasized.
• The two fabrication ways are suggested for integrated-optical and biomedical applications.

Patterned LiNbO3 thin films basing aqueous precursor are fabricated in photolithography and laser-induced crystallization ways. The effects of LN gel solubility, laser scanning parameters and substrate temperature on the pattern quality of LN film are demonstrated. We emphasize the importance of the temperature gradient at the crystallization front to the pattern quality for laser-induced crystallization. Moreover, the distinct morphology features (porous and compact) of patterned LN films fabricated in the two ways are shown and explained by their difference of crystallization modes. These two fabrication ways are suggested for the integrated-optical and biomedical applications, respectively.