Metrology for 3D Integration

Three-dimensional stacked integrated circuit (3DS-IC) fabrication requires complex technologies such as high-aspect ratio through-silicon vias (TSVs), wafer thinning, thin wafer handling and processing, and bonding of thin wafers with complex patterned surfaces. Each of these new fabrication steps is associated with metrology challenges. The SEMI 3DS-IC Committee is developing a set of guides to assist the 3DS-IC community in addressing these challenges by identifying metrology solutions. In this paper we provide an overview of the metrology needs for 3DS-IC, identify metrology solutions, and provide examples from SEMI standards describing methods for characterizing the quality and strength of bonds between wafers.