AlN-AlN Wafer Bonding and Its Thermal Characteristics

Abstract

Homogeneous bonding was successfully demonstrated on 150 mm Si wafers by face-to-face fusion bonding of two clean and smooth aluminum nitride (AlN) layers. Characterization result from XPS confirms the layer composition and reveals that approximately 5 nm of the layer surface was partially oxidized during processing. The as-bonded wafer pair is nearly void and particle free with a high bonding strength of 1263.0 mJ/m2, enabling it to withstand the subsequent process steps. In addition, the AlN-AlN bonded wafers appear to have the best heat dissipation capability when compared with other bonded wafers, which used SiO2 or Al2O3 as the bonding layer.