Investigation of the Dilation of Epoxy with Negative Thermal Expansion Fillers

The bonding glue is well used in packaging of the opto-electronic elements. The light paths of the elements are aligned accurately before bonding, the coefficient of thermal expansion of bonding glue is much more large than the one of silicon based optoelectronic elements, the light paths of the elements are thus misalignment after the bonding. The silica filler is usually mixed into the bonding glue for lowering the coefficient of thermal expansion. In this paper, the ceramic powder of the ZrW2O8 with negative coefficient of thermal expansion is thus mixed the commercial bonding glue for deriving of the extra low dilation adhesion. The thermal expansion of the composite bonding glue with negative coefficient of thermal expansion fillers is measured accurately to compare with the filler of silica powder. The results show that a composite glue with the very low coefficient of thermal expansion is therefore acquired for packaging of optoelectronic elements.