1. A method for generating a depth profile of a junction formed in a dopant implanted semiconductor wafer comprising the steps of: measuring the modulated optical reflectivity of the wafer and generating output signals in response thereto, said measurements being obtained by periodically exciting the wafer with an intensity modulated pump beam having an energy and modulation frequency sufficient to create thermal and plasma waves that effect the reflectivity of the wafer and monitoring the modulated optical reflectivity changes with a separate probe beam; comparing the measurement results to calibration samples to determine the junction depth, active dopant concentration and profile abruptness; constructing a junction depth profile based on the determined junction depth, active dopant concentration and abruptness; and displaying or storing the depth profile.