Share Email Print

Proceedings Paper

Design-based metrology: beyond CD/EPE metrics to evaluate printability performance
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Process-window (PW) evaluation is critical to assess the lithography process quality and limitations. Usual CD-based PW gives only a partial answer. Simulations such as Tachyon LMC (Lithography Manufacturability Check) can efficiently overcome this limitation by analyzing the entire predicted resist contours. But so far experimental measurements did not allow such flexibility. This paper shows an innovative experimental flow, which allows the user to directly validate LMC results across PW for a select group of reference patterns, thereby overcoming the limitations found in the traditional CD-based PW analysis. To evaluate the process window on wafer more accurately, we take advantage of design based metrology and extract experimental contours from the CD-SEM measurements. Then we implement an area metric to quantify the area coverage of the experimental contours with respect to the intended ones, using a defined “sectorization” for the logic structures. This ‘sectorization’ aims to differentiate specific areas on the logic structures being analyzed, such as corners, line-ends, short and long lines. This way, a complete evaluation of the information contained in each CD-SEM picture is performed, without having to discard any information. This solution doesn’t look at the area coverage of an entire feature, but uses a ‘sectorization’ to differentiate specific feature areas such as corners, line-ends, short and long lines, and thus look at those area coverages. An assessment of resist model/OPC quality/process quality at sub nm-level accuracy is rendered possible.

Paper Details

Date Published: 25 March 2016
PDF: 11 pages
Proc. SPIE 9778, Metrology, Inspection, and Process Control for Microlithography XXX, 97780W (25 March 2016); doi: 10.1117/12.2221894
Show Author Affiliations
Sandip Halder, imec (Belgium)
Julien Mailfert, imec (Belgium)
Philippe Leray, imec (Belgium)
David Rio, ASML (Belgium)
Yi-Hsing Peng, ASML Brion (United States)
Bart Laenens, ASML Brion (United States)

Published in SPIE Proceedings Vol. 9778:
Metrology, Inspection, and Process Control for Microlithography XXX
Martha I. Sanchez, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?