Techniques in Failure Analysis of MOS Devices

The greatest concern on MOB devices is the physical integrity of the gate oxide. Leakage paths and/or shorts through defect sites in the oxide are a major device reliability problem. Optical microscopy is tedious and often does not resolve the defects. With this in mind, copper decoration techniques were developed that could reveal oxide failures sites down to 0.1¿m size. The technique has isolated various failure mechanisms on MOS devices. This failure analysis capability has enhanced the ability to control the MOS process.