公开(公告)号：WO2020078677A1

公开(公告)日：2020-04-23

申请号：PCT/EP2019/075819

申请日：2019-09-25

Applicant: ASML NETHERLANDS B.V.

Inventor： BADR, Elie ,  SHAKAHWAT MILLAT, Shawn ,  MICELI, Giacomo ,  VERMA, Alok

IPC: G03F7/20

Abstract: A method for determining an overlay metric is disclosed comprising obtaining angle resolved distribution spectrum data relating to a measurement of the target structure comprising a symmetrical component. An overlay dependent contour of a feature of said target structure is determined from said angle resolved distribution spectrum data, from which an overlay metric is determined. The method comprises exposing an exposed feature onto a masked layer comprising a mask which defines masked and unmasked areas of the layer, such that a first portion of the exposed feature is exposed on a masked area of said layer and a second portion of the exposed feature is exposed on a non-masked area of said layer, the size of the first portion with respect to the second portion being overlay dependent; and performing an etch step to define an etched feature, the etched feature corresponding to said second portion of the exposed feature.

公开(公告)号：EP3640735A1

公开(公告)日：2020-04-22

申请号：EP18201147.8

申请日：2018-10-18

Applicant: ASML Netherlands B.V.

Inventor： BADR, Elie ,  SHAKAHWAT MILLAT, Shawn ,  MICELI, Giacomo ,  VERMA, Alok

IPC: G03F7/20

Abstract: A method for determining an overlay metric is disclosed comprising obtaining angle resolved distribution spectrum data relating to a measurement of the target structure comprising a symmetrical component. An overlay dependent contour of a feature (820) of said target structure is determined from said angle resolved distribution spectrum data, from which an overlay metric is determined. The method comprises exposing an exposed feature onto a masked layer comprising a mask which defines masked and unmasked areas of the layer, such that a first portion of the exposed feature is exposed on a masked area of said layer and a second portion of the exposed feature is exposed on a non-masked area of said layer, the size of the first portion with respect to the second portion being overlay dependent; and performing an etch step to define an etched feature, the etched feature corresponding to said second portion of the exposed feature.