Paper
13 March 2012 New methodology to predict pattern collapse for 14nm and beyond
Author Affiliations +
Abstract
Critical aspect ratio induced pattern collapse has been a concern for lithography process engineers since before the 180 nm node. This line bending can lead to pattern deformation or complete substrate adhesion failure. Several process improvements, such as surfactant-laced final rinse, have been proposed to alter surface energies and increase the critical aspect ratio for collapse. The challenge is more severe for sub-60 nm pitch ground-rules that are being developed for the 14 nm technology node, since 30nm and smaller spaces will produce extremely large capillary forces acting on very narrow resist patterns. In previous studies, an analytical model was used to predict pattern collapse of simplified line/space structures. In this work, we propose a new framework to predict pattern collapse of sub-60 nm pitch EUV resist structures by the use of a semi-empirical model. This semi-empirical model is derived from the one-dimensional analytical model, which includes a term dependent on the local pattern geometry and the physical properties of the resist and rinse solution. We calibrate/verify the model with various EUV pattern collapse data collected from onedimensional (e.g., line/space) patterns. Hotspots predicted by the semi-empirical model are compared with those obtained from EUV wafer exposures. Weaknesses in model prediction were then used to adjust the model terms. Determining pattern collapse and identifying hot-spots early in the development cycle is critical for setting restricted design rules and refining DFM/RET solutions.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Aasutosh Dave, Kenji Yoshimoto, and John Sturtevant "New methodology to predict pattern collapse for 14nm and beyond", Proc. SPIE 8326, Optical Microlithography XXV, 83261K (13 March 2012); https://doi.org/10.1117/12.917885
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Extreme ultraviolet

Photoresist materials

Calibration

Capillaries

Data modeling

Semiconducting wafers

Extreme ultraviolet lithography

RELATED CONTENT

EUV OPC modeling and correction requirements
Proceedings of SPIE (March 18 2014)
Availability of underlayer application to EUV process
Proceedings of SPIE (April 08 2011)
Predictive modeling of EUV lithography the role of mask,...
Proceedings of SPIE (October 04 2011)
Full chip correction of EUV design
Proceedings of SPIE (March 20 2010)

Back to Top