A method is disclosed for determining the inactive doping concentration of a semiconductor region using a PMOR method. In one aspect, the method includes providing two semiconductor regions having substantially the same known as-implanted concentration but known varying junction depths. The method includes determining on one of these semiconductor regions the as-implanted concentration. The semiconductor regions are then partially activated. PMOR measures are then performed on the partially activated semiconductor regions to measure (a) the signed amplitude of the reflected probe signal as function of junction depth and (b) the DC probe reflectivity as function of junction depth. The method includes extracting from these measurements the active doping concentration and then calculating the inactive doping concentration using the determined total as-implanted concentration and active doping concentration. The method may also include extracting thermal diffusivity, refraction index, absorption coefficient, and/or SRHF lifetime from these measurements.