Effect of oxygen plasma treatment on anodic bonding

Abstract

Oxygen plasma surface treatment of silicon and glass was studied for improving the characteristics of anodic bonding. By using the sessile drop method, we confirmed that the surfaces activated by the oxygen plasma were rendered hydrophilic even at low r.f. power or short plasma exposure time. With increasing plasma power and exposure time the surface roughness was observed to increase. The oxygen plasma treatment was significantly efficient in reducing the impurities on the surface, which caused degradation in the bonding strength and the electrical property in interface. In the tensile test, the oxygen plasma treatment led to a higher bonding strength than the conventional anodic bonding method.