Diagnosis of Defects on Global Signals

Global control signals account for over 10% of the circuit area and are challenging to diagnose when defects occur. This paper introduces a global signal diagnosis technique that can be easily integrated into the existing chain failure diagnosis flow in volume diagnosis. In addition to clock and scan enable signals, set and reset signals are also taken into account during diagnosis. The layout topology of global nets is utilized to improve the accuracy and resolution of the diagnosis result. The effectiveness of this method is validated through several physical failure analysis results.