Voltage Skew-Based Test Technique for Pre-Bond TSVs in 3-D ICs

In 3D ICs, the manufacturing process of through silicon via (TSV) is still immature, which can result in resistive open faults and leakage faults. Pre-bond TSV tests can effectively improve the performance and yield of 3D ICs. In the paper, a new pre-bond TSV test method based on the voltage skew is proposed. The proposed method charges a pre-set load capacitor during the voltage skew between faulty and fault-free TSV. It then measures the charge time to detect TSV faults. Furthermore, a variable drive inverter is designed to change the duration of voltage skew and recharge the load capacitor. By comparing the twice charge time, the type of TSV faults can be identified. The experimental results show that the proposed method can detect resistive open faults with Ropen≥400Ω and leakage faults with Rleak≤20MΩ. Compared to other test methods, the proposed method has higher detection capability.