4-Layer Wafer on Wafer Stacking Demonstration with Face to Face/Face to Back Stacked Flexibility Using Hybrid Bond/TSV-Middle for Various 3D Integration. - C.-L. Lu; C.-H. Chuang; C.-H. Huang; S.-C. Lin; Y.-H. Chang; W.-Y. Lai; M.-H. Chiu; Ming Han Liao; S.-Z. Chang (VLSI Technology and Circuits, 2023)