When substrate is processed, also any measurement grating marks available on the substrate will be influenced: they will be deformed asymmetrically, which gives rise to a measurement-shift error when measuring such a grating mark. To measure on a processed mark, an algorithm is used. This algorithm describes a method to calculate the weight factor of the information from each order. The weight factors of such an algorithm are based on a model which describes the measurement position as a function of the diffraction orders and the mark position. This paper proposes an algorithm for finding these weight factors, and the feasibility of the method is validated through simulation.

Date Published: 6 March 2015
PDF: 9 pages
Proc. SPIE 9446, Ninth International Symposium on Precision Engineering Measurement and Instrumentation, 94462M (6 March 2015); doi: 10.1117/12.2181178

Published in SPIE Proceedings Vol. 9446:
Ninth International Symposium on Precision Engineering Measurement and Instrumentation
Junning Cui; Jiubin Tan; Xianfang Wen, Editor(s)