A Pulse Shrinking-Based Test Solution for Prebond Through Silicon via in 3-D ICs

Abstract

Since the physical defects such as resistive open and leakage in through silicon vias (TSVs) caused by immature manufacturing techniques tend to undermine the reliability and yield of 3-D integrated circuits, it is very important to test the TSV as early as possible in the fabrication process. There are some shortcomings in the existing prebond TSV test techniques, such as incomprehensive fault coverage, large area overhead, and additional test time. To overcome these problems, a noninvasive solution for prebond TSV test based on pulse shrinking is proposed in this paper. This method makes use of the fact that defects in TSV lead to variation in the propagation delay—the rise and fall times are first transformed into pulse width, and the pulse shrinking technique is used to digitize the pulse width into a digital code which is then compared with an expected value for a fault-free TSV. Experiments on defect detection are carried out using HSPICE simulations with realistic models for 45-nm CMOS technology. The results show that the proposed method performs better than the existing methods in terms of fault coverage, area overhead, and test time.