Variance Analysis for Overlay Errors in Semiconductor Lithography Equipment

Abstract

In semiconductor lithography equipment, overlay errors are caused by various factors such as poor adjustment of the equipment, wafer deformation through the process, and environmental unstability of atmospheric pressure and temperature.
To explore key factors of overlay errors, this paper proposes a method of performing detailed analysis of overlay error variance.
In addition, new analysis method is explained, and an actual example of the analysis is shown.