Influence of Various Plasma and UV/O3Treatments on Au Surfaces for Au-Au Surface Activated Bonding

Au-Au surface activated bonding has been widely studied because of its potential for room temperature bonding in air atmosphere. In this paper, we investigate the effect of Ar and
$\mathrm{O}_{2}$
plasma treatments and
$\text{UV}/\mathrm{O}_{3}$
treatment on room-temperature wafer bonding using Au thin films. X-ray photoelectron spectroscopy analysis showed that all treatments can effectively remove organic contaminants on Au surfaces. However, bonding strength was significantly high only in the case of Ar plasma treatment. It is concluded that Ar plasma treatment by physically bombarding with Ar ions is suitable for room temperature Au-Au bonding compared with O
2
plasma and UV/O
3
treatments by chemical reaction.