This paper demonstrates capacitance-voltage (CV) measurements using Nanoprobing to characterize different fails and better understand the defect mode. Three case studies are conducted using the CV technique. DC Nanoprobing measurements are first used to identify the failure mode. Subsequently, CV measurements are employed to further narrow down the root cause, to understand the process mechanism leading to the failure. A pathway to use the CV technique to isolate defects with-in a device under test is also demonstrated. It has been shown that the gate to lightly doped drain CV measurements will be a very useful characterization tool to understand various fail modes. This finding, along with DC measurement, serves to narrow the issue primarily to gate stack work function related matters.