  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.
