Silicon-to-silicon anodic bonding with a borosilicate glass layer

Anodic bonding of silicon wafers by sputter deposited glass films, silicon-to-silicon anodic bonding, is presented as a promising sealing method in microengineering. A reliable process for wafer-to-wafer bonding is described and data concerning yield and bonding strength are given. Cathodic bonding is reported in a discussion about the bonding mechanism. Different sputter deposited and annealed Pyrex 7740 layers are evaluated as sealing material. Some advantages of silicon-to-silicon anodic bonding as a mounting method for micromechanical sensors are quantified.