High-Thermoresistant Temporary Bonding Technology for Multichip-to-Wafer 3-D Integration With Via-Last TSVs

In this paper, a high-thermoresistant temporary bonding/debonding system using spin-on glass (SOG) and hydrogenated amorphous silicon layers is proposed for the multichip-to-wafer (MCtW) 3-D integration based on a via-last/backside-via through-silicon via (TSV) approach. The shear strengths of chips bonded to wafers through the SOG layers are evaluated. In addition, the debonding performance of the chips from the wafers is investigated by using the KrF excimer laser irradiation. Finally, a via-last/backside-via MCtW 3-D integration process using the temporary bonding/debonding system is demonstrated to show the high feasibility with the successful interconnect formation of a Cu-TSVs daisy chain (10 mu m in diameter and 50 mu m in depth) with a SiO2 liner dielectric deposited by O-3-tetraethylorthosilicate chemical vapor deposition at 350 degrees C.