Effectiveness of High Bias Voltage IREM on Elevated VminFailure: Case Study

Infra-Red Emission Microscopy (IREM) is a widely used technique for CMOS silicon Fault Isolation (FI) [1] [2]. Poor Signal-to-Noise Ratio (SNR) at low voltage is a key limitation for this technology to be widely used for FI on marginal failures or also known as Vmin (minimum operating voltage) limiting failures [3]. Given that, Laser Assisted Device Alteration (LADA) is widely used for Vmin failures. However, it's accuracy in identifying the defect location is always questionable as LADA uses the tester to determine the pass/fail criteria [4]. This paper presents two case studies demonstrating how IREM can be used for FI of elevated Vmin failures by not restricting the analysis to the failing voltage region.