Detection of Resistive Shorts and Opens using Voltage Contrast Inspection

The ability of voltage contrast inspection to detect resistive opens and shorts was investigated. Resistive programmed defects ranging from 8 kOmega to 4 MOmega, were created using integrated poly-silicon resistors. While all the shorts were easily detected, only the 4 MOmega, open had a signal, and it was too faint for automatic detection. A model is presented to help explain these results. A follow-up study with resistances in the MOmega range is now in progress. Based on the experimental and modeling work described in this paper, we anticipate the threshold for detection of resistive opens will be between 10 and 20 MOmega