In one aspect, the present invention is a system and method for obtaining information
regarding one or more contact holes and/or vias on a semiconductor wafer. In this
regard, in one embodiment, the system comprises an electron gun to irradiate an
electron beam, having a variable acceleration voltage, on the one or more contact
holes and/or vias. The system further includes a current measuring device, coupled
to the semiconductor wafer, may measure a compensation current, wherein the compensation
current is generated in response to the electron beam irradiated at a plurality
of acceleration voltages on the one or more contact holes. The system also includes
a data processor, coupled to the current measuring device, to determine information
relating to the one or more contact holes and/or vias using the compensation current
measured for the plurality of acceleration voltages of the electron beam.