Formation of SiO₂ Bonding Interface using Perhydropolysilazane at Room Temperature

This paper presents a new approach for room temperature wafer bonding using polysilazane as a precursor for the SiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> bonding interface. Wafer bonding is a key technique for electronics packaging, but conventional methods require an undesirable annealing step due to their reliance on the formation of the SiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> bonding interface through oxidation or condensation polymerization facilitated by water adsorption. In this study, we propose and demonstrate room temperature wafer bonding achieved through the conversion of polysilazane into SiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> at the bonding interface. As a result, the bond strength at room temperature exceeds 5.5 J/m 2 without significant voids. This establishes a new method for room temperature wafer bonding.