Power Supply Noise-Aware Scan Test Pattern Reshaping for At-Speed Delay Fault Testing of Monolithic 3D ICs *

Abstract

Monolithic 3D (M3D) integration is an emerging technology that offers significant power, performance, and area benefits for integrated circuit (IC) design. However, a problem with the 3D power distribution network in such ICs is that it can lead to high power supply noise (PSN) during the capture cycles in at-speed scan testing for transition delay faults. Therefore, the failure of good chips (i.e., yield loss) resulting from the PSN-induced voltage droop is a major concern for M3D designs. In this paper, we first assess the PSN and voltage droop problems, and their impact on path delays for at-speed testing of benchmark M3D designs. Next, we present an analysis framework to identify test patterns that are most likely to lead to yield loss. We describe a test-pattern reshaping solution based on integer linear programming to make appropriate changes to the test patterns that cause yield loss. Simulation results for four M3D benchmarks highlight the effectiveness of the proposed solution.