Many different growth structures of nickel silicide on the Si(001) are present as functions of coverage and temperature. Conflicting results in macroscopic Schottky barrier height measurements are due to the fact that one of many phases may dominate carrier transport through the interface barrier. Scanning capacitance microscopy and spectroscopy were performed on NiSi2/Si(100) to measure the spatial variation of Schottky barrier height. From the intercept in an 1/C-2 vs V plot, a local Schottky barrier height can be deduced.