公开(公告)号：NL2005733A

公开(公告)日：2011-06-09

申请号：NL2005733

申请日：2010-11-22

Applicant: ASML NETHERLANDS BV

Inventor： SETIJA IRWAN ,  KRAAIJ MARKUS ,  DIRKS REMCO ,  BEURDEN MARTIJN CONSTANT

IPC: G01N21/47 ,  G03F7/20

Abstract: Numerical calculation of electromagnetic scattering properties and structural parameters of periodic structures is disclosed. A reflection coefficient has a representation as a bilinear or sesquilinear form. Computations of reflection coefficients and their derivatives for a single outgoing direction can benefit from an adjoint-state variable. Because the linear operator is identical for all angles of incidence that contribute to the same outgoing wave direction, there exists a single adjoint-state variable that generates all reflection coefficients from all incident waves that contribute to the outgoing wave. This adjoint-state variable can be obtained by numerically solving a single linear system, whereas one otherwise would need to solve a number of linear systems equal to the number of angles of incidence.