METHOD OF OBTAINING AND USING A WEIGHTING FUNCTION OF ENHANCE MEASURED DIFFRACTION SIGNALS IN OPTICAL METROLOGY, AND SYSTEM TO USE THE WEIGHTING FUNCTION

摘要

To obtain the weighting function to enhance the measured diffraction signal to be used in the optical measurement. To obtain a weighting function, and obtains the measured diffraction signal. The measured diffraction signal is measured from the site on the wafer by using a photometric device. Based on noise present in the measured diffraction signal defines a first weight function. On the basis of the accuracy of the measured diffraction signal defines a second weight function. On the basis of the sensitivity of the measured diffraction signal to define a third weighting function. On the basis of the first, second and at least one of the three weighting functions defines a fourth weighting function. ; Photometric device