Abstract
In this work, void formation was systematically observed for the glass frit bonding technique as a function of the annealing temperature, annealing time, and annealing ambient. High annealing temperature and long annealing time were adopted to reach the maximum heat flux to avoid voids/bubbles. As demonstrated in the experiments, the voids appearing during glass frit bonding are related to the quantity of byproducts from the combustion of organic matter. The experimental results indicate that solely in air, under vacuum, or annealed for short time, the combustion products cannot be fully degassed, and voids occur. It was shown that the alternating three-step conditioning process including glass liquid forming in air, bubble removal under vacuum, and void filling-up in air can lead to void-free and uniform wafer bonding. The glass frit bonding samples with lots of voids/bubbles were compared to the ones without any defects.
Funder
Guangdong Basic and Applied Basic Research Foundation
Subject
Electrical and Electronic Engineering,Mechanical Engineering,Control and Systems Engineering
Reference21 articles.
1. Fabrication of the nanofluidic channels type leak assembly based on the glass frit sealing method;Zhou;J. Vac. Sci. Technol. B,2019
2. Roy, K., Sophia, D., and Holger, K. (2016, January 2–7). Glass frit wafer bonding—Sealed cavity pressure in relation to bonding process parameters. Proceedings of the Symposium on Semiconductor Wafer Bonding—Science, Technology and Applications, Honolulu, HI, USA.
3. Influence of glass-frit material distribution on the performance of precision piezoresistive mems pressure sensors;Asmund;IEEE Trans. Compon. Packag. Manuf.,2015
4. Wafer level vacuum packaging of micro-mirrors with buried signal lines;Langa;Microsyst. Technol.,2015
5. Microwave characterization of a wafer-level packaging approach for rf mems devices using glass frit bonding;Ilker;IEEE Sens. J.,2014