Effect of SiO2/Li2O content on structure and physicochemical properties of photosensitive glass-ceramics

Abstract

Easy-to-manufacture photosensitive glass ceramics are vital for wide applications due to their superior thermal, mechanical and chemical properties from an industrial point of view, while their commercialization is strongly limited by the complex effect of material compositions and thermal treatments. Here, the effect of SiO2/Li2O content on structure and physicochemical properties of photosensitive glass-ceramics was systematically investigated. The photosensitive glass-ceramics were prepared using a melting method based on the Li2O–Al2O3–SiO2 glass system. The effect of each component content on dielectric constant, dielectric loss and etching properties of the basic glass was studied. The relationship between the structure and properties of photosensitive glass-ceramics before and after crystallization were investigated via differential scanning calorimetry (DSC), X-ray diffraction (XRD) and Raman spectroscopy measurements. The results show that when the SiO2/Li2O ratio is 76.5/9, the chemical stability of the basic glass is the highest, whereas the etching loss rate is the lowest. After UV exposure and heat treatment, acid-soluble Li2SiO3 crystals were formed inside the glass-ceramic matrix. Compared with the unexposed part, the etching ratio of the photosensitive glass-ceramic reaches its maximal value of 16/1. It is worth mentioning that after heat treatment, the dielectric constant and dielectric loss of the unexposed photosensitive glass-ceramic are slightly higher than those of the basic glass, reaching 6.67 and 5.78 × 10−3 (@1 GHz), respectively. Finally, after acid etching, photosensitive glass-ceramic is exposed via mask exposure and heat treatment to obtain holes with a diameter of 50–60 μm, which can be used as a substrate material in many fields such as communication, aerospace, biomedical and so on.