Enhancing a current leakage path using a novel dual source heating system

Abstract

Thermal laser stimulation (TLS) implemented under testing has become an important failure analysis technique for System-on-Chip (SoCs). This technique ensures that devices under testing (DUT) can enter particular modes, which turn on certain circuit blocks when performing TLS. However, from foundry's perspective, TLS operated under testing may not be a cost-effective solution as numerous design and test resources are required. This paper proposes a novel dual source heating system which can localize defects without utilizing any vectors by using a thermal laser in combination with a heating plate connected to a temperature controller. In this study, a defective SoC was globally heated using the heating plate to enhance the leakage path by changing the properties of the chip. Meanwhile, active or passive devices inside the defective SoC were locally heated using the thermal laser to enhance the defect detection capability by changing the electrical behaviors of the active or passive devices. Using this technique, a silicon defect located in an embedded functional circuit block of the defective SoC was successfully isolated without pausing the sample at any certain vectors.