Disclosed is a method for reconstructing a parameter of a lithographic process. The method comprises the step of designing a preconditioner suitable for an input system comprising the difference of a first matrix and a second matrix, the first matrix being arranged to have a multi-level structure of at least three levels whereby at least two of said levels comprise a Toeplitz structure. One such preconditioner is a block-diagonal matrix comprising a BTTB structure generated from a matrix-valued inverse generating function. A second such preconditioner is determined from an approximate decomposition of said first matrix into one or more Kronecker products.
|Publication status||Published - 21 Jun 2018|
Pisarenco, M., Schneider, F. S., van Kraaij, M. G. M. M., & van Beurden, M. C. (2018). IPC No. WO2018108503. Methods and apparatus for calculating electromagnetic scattering properties of a structure and for reconstruction of approximate structures. https://nl.espacenet.com/publicationDetails/biblio?II=0&ND=3&adjacent=true&locale=nl_NL&FT=D&date=20180621&CC=WO&NR=2018108503A1&KC=A1#