We present a technique that involves tailoring the angular spectrum in optical microscopy of silicon integrated circuits, with a solid immersion lens. Spatial light modulation to select only supercritical light at the substrate/dielectric interface yields only evanescent and scattered light in the interconnect layers. We demonstrated the technique in optical excitation microscopy of 65nm silicon-on-insulator circuits, which enabled localization of a fault during microprocessor development. Acquiring images with and without angular spectrum tailoring allowed longitudinal localization of the electrical response to optical excitation. Lateral registration of electrical response and confocal reflection images to the circuit layout was also significantly improved.

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In this paper, a new emission-based methodfor measuring the amplitude of on-chip power supply noise is pr esented. This technique uses Time Resolved Emission (TRE) waveforms of Light Emission from Off-State Leakage Current (LEOSLC) from CMOS gates, which are used as local probe points for the noise. In order to demonstrate the capabilities of this technique, we discuss the results obtained for two early microprocessor chips fab ricated in 65 nm and 45 nm Silicon On Insulator (SOl) technologies.

Failure analysis for Static Random Access Memory (SRAM) is the major activity in any microelectronic failure analysis lab. Originating from SRAM array structure, SRAM failure can be simple as single bit, paired bit or quad bit failures, whose defect is located at the failure location, or complicated as logic type failure involving WL or BL patterns or entire blocks, whose defect is often not at the failure location. For such SRAM logic type failures, failure analysis is more challenging and detailed fault isolation is necessary prior to physical failure analysis. This paper has demonstrated how to use SRAM decoder scheme knowledge, detailed layout tracing and Photon Emission Microscope (PEM) analysis to deal with the challenges and find the root causes for several cases of SRAM logic type failures.

Failure analysis plays a very important role in semiconductor industry. Photon Emission Microscopy (PEM) has been extensively used in localization of fails in microelectronic devices. However, PEM emission site is not necessarily at the location of the defect. Thus, it has limitation for the success rate of the follow-up physical failure analysis focusing on the emission site. As semiconductor technology advanced in the 3D FinFET realm and feature size further shrank down, the invisible defects during SEM inspection are tremendously increased. It leads to the success rate further decreasing. To maintain good success rate of failure analysis for advanced 3D FinFET technology, electrical probing is necessary to be incorporated into the failure analysis flow. In this paper, first, the statistic results of PEM emission sites versus real defect locations from 102 modules of microprocessors manufactured by 14nm 3D FinFET technology was present. Then, we will present how to wisely design electrical probing plan after PEM analysis. The electrical probing plans are tailored to different scan chain and ATPG failures of microprocessors for improving failure analysis success rate without increasing too much turn-around time. Finally, two case studies have been described to demonstrate how the electrical probing results guide the follow-up physical failure analysis to find the defect.