Share Email Print

Journal of Micro/Nanolithography, MEMS, and MOEMS

Resolution-linewidth roughness-sensitivity performance tradeoffs for an extreme ultraviolet polymer bound photo-acid generator resist
Format Member Price Non-Member Price
PDF $20.00 $25.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

The goal of this work is to use a combination of experiment and calibrated resist models to understand the impact of photo-acid generator (PAG) and sensitizer loading on the performance of a polymer bound PAG resist based processes for extreme ultraviolet (EUV) lithography. This paper describes construction of a chemically amplified resist model across 248 nm, 193 nm, and EUV imaging wavelengths. Using resist absorbance input as obtained from experiment and modeling, only the acid formation kinetics are allowed to vary across imaging wavelengths. This constraining system affords very good fitting results, which provides high confidence that the extracted parameters from the model have actual physical significance. The quantum efficiency for acid formation in EUV is found to be ∼8× higher than at 248 or 193 nm, due to the excitation mechanism by secondary electrons. Most notably for the polymer bound PAG system under study the model provides an extremely low acid diffusion length (∼8 nm), suggesting an excellent inherent resolution for this material. Next, resist models are created for a series of sensitizer containing polymer bound PAG formulations, where the sensitizer loading is systematically varied. Compared to the reference polymer bound PAG resist without sensitizer the efficiency of acid formation is significantly increased, without a negative impact on either resolution or linewidth roughness. For these materials the quantum efficiency of acid formation in EUV is found to be ∼12× higher than at 248 nm. In these formulations the impact of sensitizer loading on the sizing dose is found to be rather moderate. This may suggest that even at the lowest sensitizer loading studied the energy of the secondary electrons is already efficiently transferred to the PAGs.

Paper Details

Date Published: 1 January 2011
PDF: 8 pages
J. Micro/Nanolith. 10(1) 013017 doi: 10.1117/1.3555090
Published in: Journal of Micro/Nanolithography, MEMS, and MOEMS Volume 10, Issue 1
Show Author Affiliations
Roel Gronheid, IMEC (Belgium)
Alessandro Vaglio Pret, IMEC (Belgium)
Benjamen M. Rathsack, Tokyo Electron America, Inc. (United States)
Joshua S. Hooge, Tokyo Electron America, Inc. (United States)
Steven A. Scheer, Tokyo Electron America, Inc. (United States)
Kathleen Nafus, Tokyo Electron Kyushu Ltd. (Belgium)
Hideo Shite, Tokyo Electron Kyushu Ltd. (Japan)
Junichi Kitano, Tokyo Electron Kyushu Ltd. (Japan)

© SPIE. Terms of Use
Back to Top