Patent ID: 6825933
Filing Date: 2004-11-30
Classification: G01N

Abstract:
A computer-implemented reflectance method for non-destructive monitoring low dose ion implantation in a material, said method comprising the steps of:a) providing illumination on a first sample of said material, wherein said material comprises silicon or silicon-oxide wafers and said first sample is a sample wafer thereof, and wherein said illumination spans a substantially broad range of wavelengths (wl); b) obtaining non-implanted reflectance measurements (Rref) of said first sample at each of said wavelengths (Rref,wl); c) implanting said first sample with said low dose of ions and obtaining implanted reflectance measurements (Rimp,wl) of said first sample at each of said wavelengths (Rimp,wl) wherein said non-implanted reflectance measurements are substantially simultaneously obtained at a location near center of said first sample and said implanted reflectance measurements are substantially simultaneously obtained at essentially same location of said first sample; d) forming reflectance values over said wavelengths based on said non-implanted and implanted reflectance measurements; e) comparing non-implanted and implanted reflectance values and determining reflectance changes; and f) correlating an absolute value of said reflectance changes to said low dose including determining a reflectance change index value where said reflectance change index equals &Sum;wl=1901000&it;|((Rref,wl-Rimp,wl)Rref,wl)|such that said reflectance change index is directly related to said low dose.