Effect of Thin SiO 2 Layer on Silicon-on-Glass Anodic Bonding *

this paper reported the effect of SiO 2 on the silicon-on-glass anodic bonding theoretically and experimentally for the first time. Silicon glass bonding mechanism based on soft break-down of SiO 2 is established and demonstrated. The electrical model of Si-SiO 2 -Glass anodic bonding stated clearly that anodic bonding voltage must be higher than the break-down voltage of SiO 2 to start bonding. The break-down voltage of SiO 2 is proportional to its thickness. Bonding strength is finally extracted by a customized on-chip testing device. It is found that the thin SiO 2 layer on the silicon surface affects the bonding strength seriously. The bonding strength of anodic bonding with SiO 2 layer is 25% stronger than that of typical Si-Glass anodic bonding near the periphery of the silicon wafer, and 8% stronger than that of typical Si-Glass anodic bonding in the central region of the silicon wafer.