公开(公告)号：US10748272B2

公开(公告)日：2020-08-18

申请号：US15982918

申请日：2018-05-17

Applicant: Applied Materials Israel Ltd.

Inventor： Ishai Schwarzband ,  Yan Avniel ,  Sergey Khristo ,  Mor Baram ,  Shimon Levi ,  Doron Girmonsky ,  Roman Kris

IPC: G06K9/00 ,  G06T7/00 ,  G06T7/60

Abstract: An improved technique for determining height difference in patterns provided on semiconductor wafers uses real measurements (e.g., measurements from SEM images) and a height difference determination model. In one version of the model, a measurable variable of the model is expressed in terms of a function of a change in depth of shadow (i.e. relative brightness), wherein the depth of shadow depends on the height difference as well as width difference between two features on a semiconductor wafer. In another version of the model, the measurable variable is expressed in terms of a function of a change of a measured distance between two characteristic points on the real image of a periodic structure with respect to a change in a tilt angle of a scanning electron beam.