Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) Lerdemo line edge detection (black lines) of top-down CDSEM image. (b) Height-height correlation function (HHCF) of the detected edges; the slope of the function represents α, and ξ is the value for which the HHCF starts saturating. (c) PSD of the detected edges as a function of the frequency (nm −1 ). Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. Simulated lines for uncorrelated [(a), c-factor = 0], correlated [(b), c-factor ∼ −1], and anticorrelated edges [(c), c-factor = 1]. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) PSD curves of 45-nm L/S pattern exposed with dipole 40 illumination in immersion lithography (dashed and rhombic lines). The asterisk line represents the same pattern exposed with annular illumination. In the graph the two gray areas represent LF and HF cut-offs respectively of FOV and pixel dimension along the lines (y direction). (b) Top-down CDSEM of 45-nm L/S resist lines exposed with dipole 40 (top) and annular (bottom). Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) CD and CD variation (3σCD) on measure numbers. (b) 3σLWR and 3σLWR variation (3σ-3σLWR) on measure numbers. Both CD and 3σLWR values were found stable after 40 images. A further increment in measure numbers was found beneficial for CD variation, but not for 3σLWR variation. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. 3σLWR (nanometer) contributions on frequency. Frequencies higher than 40 μm −1 do not contribute to the final 3σLWR value. Frequencies lower than 20 μm −1 “contain” high 3σLWR. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. CDSEM top-down image captured with (a) 300-kx symmetric FOV = 0.450×0.450 μm 2, and (b) 300-kx x-direction and 49-kx y- direction asymmetric FOV = 0.450×2.755 μm 2. The white line was added to highlight the tilting lines. (c) and (d) are readaptations of (a) and (b) keeping the original dimensions. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a), (b), and (c) show CD and 3σLWR trends respectively upon frame number, pixel number, and magnification used to capture the CDSEM images. Increasing the e- dose by increasing frame number, pixel number, and magnification causes the CD to shrink more. (d) and (e) show PSDs of the same resist pattern captured with different magnification. Even after normalization (e), the curves are not superimposed in the low and high frequencies. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. CD (black) and 3σLWR (gray) trends on different Hitachi software image analysis filters. Different filters may affect final outputs in different ways. Substantial discrepancies in the analyses comparison were found by varying the values of these filters. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) 3σLWR uniformity (dots) and 3σLWR variance (errors bars) for long- (black) and short- (gray) period measurements. (b) 3σLWR variance bar representation of left graph errors bars. Δ3σ is the quadratic difference between long- and short-period error bars. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) and (b) show simulated CD (gray circles), 3σLER (black asterisk), experimental 3σLER (black full dots), and 3σLWR (black full triangle) on tilt angle for uncorrect (a) and correct (b) line tilting. Once the line tilting was corrected by software, experimental 3σLER did not show any dependence on tilt angle. c-factor for (c) uncorrected and (d) corrected line tilting. Also in this case the software with the tilting correction did not show any edge-correlation angle dependence. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) and (b) show top-down asymmetric SEM-CD FOV for low and high dose exposures. (c) 3σLWR (black) and photon shot noise (gray) on dose. 3σLWR decreased quadratically with the dose. (d) PSDs for different doses. Increasing the dose (from black to light- gray) decreased 3σLWR, in particular in the LF region. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) and (b) show top-down asymmetric FOV SEM images for bright- (high flare) and dark-field (low flare) exposures. (c) PSD trends for two bright-field (light-gray) and two dark-field (dark-gray) exposures. The dashed line represents the difference between the averages of these two exposures. The major contribution to the roughness due to the flare arose from the LF region. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /

Date of download: 6/2/2016 Copyright © 2016 SPIE. All rights reserved. (a) and (b) show top-down SEM images for symmetric and asymmetric FOVs for surfactant rinse plus a 150ºC hardbake smoothing process. These two images represent the same lines. (c) PSD trends for different hardbake temperatures performed with symmetric CDSEM FOV. The roughness reduction of mid- and HF is evident. (d) PSD trends for different hardbake temperatures performed with asymmetric CDSEM FOV. The mid- and HF improvements were overridden by the detrimental effect of the hardbake in the LF region. Figure Legend: From: Resist roughness evaluation and frequency analysis: metrological challenges and potential solutions for extreme ultraviolet lithography J. Micro/Nanolith. MEMS MOEMS. 2010;9(4): doi: /