Rigorous EM simulation of the influence of the structure of mask patterns on EUVL imaging

Deng, Yunfei; Fontaine, Bruno M. La; Levinson, Harry; Neureuther, Andrew R.

doi:10.1117/12.484986

Cited by 16 publications

(13 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Then, the curve flattens out significantly more than the conventional Cr/SiO 2 absorber stack. This result is understandable since it was demonstrated by Deng et al [2] that beside a higher aerial image contrast, 99.96%, the multilayer etch structures reflects only 0.09% of the substrate surface in the etched trench. Therefore the light reflected back from the substrate is not very sensitive to the side wall angle, and its interference with the light from the top surface is minimal.…”

Section: Simulationsupporting

confidence: 60%

“…As shown in a previous work [2] , it is desirable for the EUV mask to have high contrast at the inspection wavelength in order to improve inspection sensitivity. Table 1 shows the etched multilayer mask to provide higher contrast and therefore better inspection sensitivity at the inspection wavelength.…”

Section: Inspectionmentioning

confidence: 96%

“…The effect of new patterning techniques for EUVL masks on defect inspection, defect repair, cleaning and on the image process are now being investigated [3,4] . It was demonstrated through simulation the superiority of subtractive patterning against the conventional patterning [2] .…”

Section: Introductionmentioning

confidence: 99%

“…Many authors have demonstrated the patterning of EUVL masks using different types of absorber stacks that were deposited on top of the multilayer reflector [1] . More recently, a new approach based on the etching of the multilayer reflector in order to define the mask pattern was proposed [2] . Using rigorous electro-magnetic simulations, it was shown that this subtractive approach could provide better process latitude, less H-V bias and smaller image-placement errors compared to the traditional masks based on the additive method.…”

mentioning

confidence: 99%

See 3 more Smart Citations

EUV mask making: an approach based on the direct patterning of the EUV reflector

et al. 2003

Self Cite

View full text Add to dashboard Cite

Extreme Ultraviolet Lithography (EUVL) is the leading candidate for manufacturing integrated circuits beyond the 45-nm technology node. The masks for EUVL are reflective and significantly different from current transmission masks for deep UV lithography. Many authors have demonstrated the patterning of EUVL masks using different types of absorber stacks that were deposited on top of the multilayer reflector [1] . More recently, a new approach based on the etching of the multilayer reflector in order to define the mask pattern was proposed [2] . Using rigorous electro-magnetic simulations, it was shown that this subtractive approach could provide better process latitude, less H-V bias and smaller image-placement errors compared to the traditional masks based on the additive method. Even though the mask processing shows interesting challenges, this approach might offer immediate advantages over the more traditional patterning technique using the absorber stack, beyond those predicted for lithography imaging. These include the possibility to use optical inspection in transmission mode, which can provide the high-contrast images that are essential for high-sensitivity detection of small defects. In this paper, we present the first results on the patterning of EUVL masks using the direct etching the EUVL multilayer reflector (Mo/Si type) to produce EUV binary masks. In particular, we show how the process parameters can be adjusted to control the pattern side wall angle. We also present an analysis of the influence of this side wall angle on lithography imaging, based on lithography simulations. Finally, we show results from the optical inspection of these etched-multilayer binary masks (EMBM).

show abstract

Section: Simulationsupporting

confidence: 60%

Section: Inspectionmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

EUV mask making: an approach based on the direct patterning of the EUV reflector

et al. 2003

Self Cite

View full text Add to dashboard Cite

show abstract

“…Various forms of etched multilayer configurations were proposed and investigated with the goal to realize phase shift masks for EUV lithography [34][35][36][37]. Aside from the technical challenges to fabricate these masks, the design and the comparison of their lithographic performance to standard mask stacks is far from trivial.…”

Section: Alternative Mask Stacksmentioning

confidence: 99%

Characterization and mitigation of 3D mask effects in extreme ultraviolet lithography

Erdmann

Evanschitzky

et al. 2017

Advanced Optical Technologies

View full text Add to dashboard Cite

Abstract:The reflection and diffraction of extreme ultraviolet (EUV) light from lithographic masks and the projection imaging of these masks by all-reflective systems introduce several significant imaging artifacts. The off-axis illumination of the mask causes asymmetric shadowing, a size bias between features with different orientations and telecentricity errors. The image contrast varies with the feature orientation and can easily drop far below intuitively expected values. The deformation of the wavefront or phase of the incident light by thick absorbers generates aberration-like effects, especially variations of the best-focus (BF) position vs. the pitch and size of the imaged patterns. Partial reflection of light from the top of the absorber generates a weak secondary image, which superposes with the main image. Based on a discussion of the root causes of these phenomena, we employ mask diffraction and imaging analysis for a quantitative analysis of these effects for standard EUV masks. Simulations for various non-standard types of mask stacks (e.g. etched multilayers, buried shifters, etc.) and for various non-standard absorber materials are used to explore the imaging capabilities of alternative masks for EUV lithography. Finally, an outlook at anamorphic systems for larger numerical apertures is given.

show abstract

Mask Materials and Designs for Extreme Ultra Violet Lithography

Kim

Ahn

2018

Electron. Mater. Lett.

View full text Add to dashboard Cite

Rigorous EM simulation of the influence of the structure of mask patterns on EUVL imaging

Cited by 16 publications

References 0 publications

EUV mask making: an approach based on the direct patterning of the EUV reflector

EUV mask making: an approach based on the direct patterning of the EUV reflector

Characterization and mitigation of 3D mask effects in extreme ultraviolet lithography

Mask Materials and Designs for Extreme Ultra Violet Lithography

Contact Info

Product

Resources

About