Characterizing Voltage Contrast in Photoelectron Emission Microscopy

A non-destructive technique for obtaining voltage contrast information with photoelectron emission microscopy (PEEM) is described. Samples consisting of electrically isolated metal lines were used to quantify voltage contrast in PEEM. The voltage contrast behavior is characterized by comparing measured voltage contrast with calculated voltage contrast from two electrostatic models. Measured voltage contrast was found to agree closely with the calculated voltage contrast, demonstrating that voltage contrast in PEEM can be used to probe local voltage information in microelectronic devices in a non-intrusive fashion.