A New Method of TGVs for Fast Filling of Metal Paste

Through glass via (TGV) is a technology based on the wafer-level fabrication of glass substrates to realize vertical interconnection of electrical signals, which has the advantages of high frequency, low transmission loss, and high insulation, and has a wide range of application prospects in the fields of RF chip and sensing chip packaging. In order to provide a new method for fabricating TGVs, this study investigates the use of laser-induced etching to complete glass microvias construction and screen thick film printing to complete the metal filling of glass microvias. By examining the relationship between the concentration of the corrosion solution, reaction time, and microporous morphology in laser-modified glass, a standardized procedure for creating various glass microvias was developed; By observing the sidewall and surface morphology of glass microporous metals with microvia sizes of
$68 \mu\mathrm{m}, 85 \ \mu\mathrm{m}$
, and
$128 \mu\mathrm{m}$
, and testing the shrinkage and resistivity of microporous metals. The experimental results show that the glass microvia surface fabricated in this work is free of stress cracks. In addition, the shrinkage of the TGV sidewall metal paste is less than 9%, the resistivity is less than
$2.4 \times 10^{\wedge}(-4)\Omega\cdot\text{cm}$
, and an aspect ratio as high as 15:1. Therefore, the research work in this paper provides a novel fabrication method for the fast and low-cost fabrication of TGVs.