Study on the 3-D laser inverse scattering phase method for evalauting microstructure

摘要

The three-dimensional (3_D) laser inverse scattering pahse method offers the advantage of measuring a 3-D microprofile within the whole area illuminated by laser beam at one time. No scanning process is required as you see in SPM (Scanning Probe Microscope). So, this method finds application where the in-process measurement of a 3-D microprofile with accuracy in the nanometer order is required for the process error evaluation. The work reported in this paper deals with development of a new iterative Fourier phase retrieval algorithm based on practical objet-domain constraints and actual measurements of a NIST traceable surface topography reference with rectangular pockets 44nm deep at intervals of 10mum. The results obtained in the measurements show the validity of the newly developed laser inverse scattering phase method.