Modeling the EUV multilayer deposition process on EUV blanks

Jindal, V. K.; Kearney, Patrick A.; Harris-Jones, Jenah; Hayes, A.; Kools, J.C.S.

doi:10.1117/12.879467

Cited by 12 publications

(7 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The details of the growth model have been discussed elsewhere. 16,17 In our previous work, 18,19 using level-set modeled multilayer growth over native defect shapes, we showed good comparison between through-focus aerial image intensities as obtained at Actinic Inspection Tool (AIT) 20 and those obtained through defect printability simulations.…”

Section: Introductionmentioning

confidence: 76%

Evaluating printability of buried native extreme ultraviolet mask phase defects through a modeling and simulation approach

Upadhyaya¹,

Jindal²,

Basavalingappa³

et al. 2015

J. Micro/Nanolith. MEMS MOEMS

View full text Add to dashboard Cite

Since completely defect-free masks will be hard to achieve, it is essential to have a good understanding of the printability of the native extreme ultraviolet (EUV) mask defects. In this work, we performed a systematic study of native mask defects to understand the defect printability they cause. The multilayer growth over native substrate mask blank defects was correlated to the multilayer growth over regular-shaped defects having similar profiles in terms of their width and height. To model the multilayer growth over the defects, a multilayer growth model based on a level-set technique was used that took into account the tool deposition conditions of the Veeco Nexus ion beam deposition tool. Further, the printability of the characterized native defects was studied at the SEMATECH-Berkeley Actinic Inspection Tool (AIT), an EUV mask-imaging microscope at Lawrence Berkeley National Laboratory. Printability of the modeled regular-shaped defects, which were propagated up the multilayer stack using level-set growth model, was studied using defect printability simulations implementing the waveguide algorithm. Good comparison was observed between AIT and the simulation results, thus demonstrating that multilayer growth over a defect is primarily a function of a defect's width and height, irrespective of its shape.

show abstract

Section: Introductionmentioning

confidence: 76%

Evaluating printability of buried native extreme ultraviolet mask phase defects through a modeling and simulation approach

Upadhyaya¹,

Jindal²,

Basavalingappa³

et al. 2015

J. Micro/Nanolith. MEMS MOEMS

View full text Add to dashboard Cite

show abstract

“…These results suggest that various problems may occur even if the temperature increase and deformation are suppressed by using an electrostatic chuck, H 2 flow, or some other cooling method. [27][28][29][30][31][32] We plan to create a model that can estimate the actual process through the development of various models that include the aforementioned cooling processes.…”

Section: Discussionmentioning

confidence: 99%

Modeling of thermomechanical changes of extreme-ultraviolet mask and their dependence on absorber variation

Ban¹,

Park²,

Park³

et al. 2018

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

Thermal and structural deformation of extreme-ultraviolet lithography (EUVL) masks during the exposure process may become important issues as these masks are subject to rigorous image placement and flatness requirements. The reflective masks used for EUVL absorb energy during exposure, and the temperature of the masks rises as a result. This can cause thermomechanical deformation that can reduce the pattern quality. The use of very thick low-thermal-expansion substrate materials (LTEMs) may reduce energy absorption, but they do not completely eliminate mask deformation. Therefore, it is necessary to predict and optimize the effects of energy transferred from the extreme-ultraviolet (EUV) light source and the resultant patterns of structured EUV masks with complex multilayers. Our study shows that heat accumulates in the masks as exposure progresses. It has been found that a higher absorber ratio (pattern density) applied to the patterning of EUV masks exacerbates the problem, especially in masks with more complex patterns.

show abstract

“…The multilayer growth model, we developed, 14,15 looks at the deposition conditions of the Veeco Instruments' Nexus low defect density tool located in the SEMATECH cleanroom facility in Albany, New York. The tool consists of an ion source, Si, Mo, and Ru targets, and an electrostatic chuck to hold the mask substrate.…”

Section: Multilayer Growth Modelmentioning

confidence: 99%

“…The details of the experimental and modeling results are reported elsewhere. 15,16 Level-set method was later used to determine the multilayer growth on defect interface with input of sputtered atom flux (of the target materials) reaching the substrate, rotational speed of substrate, and other deposition parameters such as substrate and target angles. The substrate rotation that is commonly used to improve uniformity in the Veeco Nexus tools was modeled to take into account the shadowing effects at defect location.…”

Section: Multilayer Growth Modelmentioning

confidence: 99%

Level-set multilayer growth model for predicting printability of buried native extreme ultraviolet mask defects

Upadhyaya

Basavalingappa

Herbol

et al. 2015

Journal of Vacuum Science &Amp; Technology B, Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phen

Self Cite

View full text Add to dashboard Cite

The availability of defect-free masks is considered to be a critical issue for enabling extreme ultraviolet lithography (EUVL) as the next generation technology. Since completely defect-free masks will be hard to achieve, it is essential to have a good understanding of the printability of EUV mask defects. In this work, two native mask blank defects were characterized using atomic force microscopy (AFM) and cross-section transmission electron microscopy (TEM), and the defect printability of the characterized native mask defects was evaluated using simulations implementing the finitedifference time-domain and the waveguide algorithms. The simulation results were compared with through-focus aerial images obtained at the SEMATECH Berkeley Actinic Inspection Tool (AIT), an EUV mask-imaging microscope at Lawrence Berkeley National Laboratory. The authors found agreement between the through-focus simulation results and the AIT results. To model the Mo/Si multilayer growth over the native defects, which served as the input for the defect printability simulations, a level-set technique was used to predict the evolution of the multilayer disruption over the defect. Unlike other models that assume a constant flux of atoms (of materials to be deposited) coming from a single direction, this model took into account the direction and incident fluxes of the materials to be deposited, as well as the rotation of the mask substrate, to accurately simulate the actual deposition conditions existing inside the ion beam deposition tool. The modeled multilayer growth was compared to the cross-section TEM images through the defects, as well as to the AFM scans for the given defects, and a good agreement was observed between them.

show abstract

Modeling the EUV multilayer deposition process on EUV blanks

Cited by 12 publications

References 9 publications

Evaluating printability of buried native extreme ultraviolet mask phase defects through a modeling and simulation approach

Evaluating printability of buried native extreme ultraviolet mask phase defects through a modeling and simulation approach

Modeling of thermomechanical changes of extreme-ultraviolet mask and their dependence on absorber variation

Level-set multilayer growth model for predicting printability of buried native extreme ultraviolet mask defects

Contact Info

Product

Resources

About