An Efficient and Non-destructive Grounding Method for Passive Voltage Contrast Fault Isolation

Voltage contrast is widely utilized as a localization method for opens (or shorts) on circuits and test structures. Conventional Passive Voltage Contrast grounding methods are mainly grouped into two types. First method, laser ablation forming a hole down to substrate and connecting the substrate with grounding pad using Focused Ion Beam (FIB) Pt deposition. Second method, FIB ion mill a hole down to substrate and then connect substrate with grounding pad using FIB Pt deposition. New grounding method using OmniProbe micromanipulator introduced to eliminate contamination due to laser ablation, re-deposition during FIB milling and it is non-destructive with the ease to switch grounding pad as needed.