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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. [ABSTRACT FROM PUBLISHER]

Electrical characteristic changes in scaled MOSFET devices have been widely reported due to electron beam (EB) irradiation. For local oxidation of silicon (LOCOS) devices, the effects of EB-induced damage when performing measurements using an SEM based nanoproer, however, have rarely been reported. EB penetration into the dielectrics, resulting in the modification of the physical properties of the dielectric layer, could be a concern, not only for scaled devices, but also for LOCOS devices. This study reveals that the effect of EB on LOCOS devices can be measured using a scanning electron microscope (SEM) based nanoprober with inducing electrical characteristic changes. These changes are accounted for by the hole trapping at the birdsbeak, which has a significant effect on both the junction electrical characteristics and punchthrough characteristics in LOCOS isolation structures when an SEM is employed for probe guidance. Further, some preliminary experimental results, not included in this paper, show that lowering the EB acceleration voltage is found to not be able to significantly eliminate the effects of EB-induced damage during device inspections in failure analysis procedures. More advanced studies are currently under investigation. [ABSTRACT FROM PUBLISHER]

It has been widely revealed that the Atomic Force Microscope (AFM) laser beam may induce photoperturbation which can significantly deteriorate the characterization accuracy of AFM-based tools. This paper gives direct evidence that the optical excitation process may yield a temporary source of minority carriers, and that the inversion layer can be formed beneath the oxide layer of the NMOS transistor. By taking advantage of this non-negligible photoelectric effect, a novel approach that is likely to be used to evaluate gate oxide quality or gate oxide reliability was developed. In this study, it was observed that defective gate oxide can cause junction photocurrent changes, or the junction photocurrent can be correlated to gate oxide quality. [ABSTRACT FROM PUBLISHER]