Share Email Print

Proceedings Paper

Transistor layout configuration effect on actual gate LER
Author(s): Guy Ayal; Eitan Shauly; Israel Rotshtein; Ovadya Menadeva; Amit Siany; Ram Peltinov; Yosi Shacham-Diamand
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

The importance of Line Edge Roughness (LER) and Line Width Roughness (LWR) has long surpassed its effect on process control. As devices scale down, the roughness effects have become a major hindrance for further advancement along Moore's law. Many studies have been conducted over the years on the sensitivity of LER to various changes in the materials and the process, which have been considered the main way to tackle the problem - especially through Photoresist improvement. However, despite the increased development of DFM tools in recent years, limited research was done as to LER sensitivity to layout, and the research that was done was limited to proximity effects. In this paper, we study the sensitivity of LER to the layout around the transistor, defined by the gate structure of poly over AA (Active Area). Using different types and geometries of transistors, we found that the poly-gate LER is sensitive to the structure of the Active Area around it (source/drain from gate to contact, both shape and length). Using local LER measurement (moving standard deviation of poly edge location), we found a clear correlation between LER value and the length of the AA/STI boundary located at a close range. Longer AA edges yield higher LER, as proved by comparing gate LER of dog-bone transistor with classical transistor. Based on these results, we suggest that LER is sensitive not only to proximity effects, but also to the layout of underlying layers, through the effect of light scattering of the edges during the lithographic process.

Paper Details

Date Published: 12 March 2009
PDF: 7 pages
Proc. SPIE 7275, Design for Manufacturability through Design-Process Integration III, 72750Y (12 March 2009); doi: 10.1117/12.813953
Show Author Affiliations
Guy Ayal, Tower Semiconductor Ltd. (Israel)
Tel-Aviv Univ. (Israel)
Eitan Shauly, Tower Semiconductor Ltd. (Israel)
Israel Rotshtein, Tower Semiconductor Ltd. (Israel)
Ovadya Menadeva, Applied Materials, Inc. (Israel)
Amit Siany, Applied Materials, Inc. (Israel)
Ram Peltinov, Applied Materials, Inc. (Israel)
Yosi Shacham-Diamand, Tel-Aviv Univ. (Israel)

Published in SPIE Proceedings Vol. 7275:
Design for Manufacturability through Design-Process Integration III
Vivek K. Singh; Michael L. Rieger, 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?