Exploring photomask etching capabilities for new extreme ultraviolet absorber materials

Rebecca D. Stern; Jeff Chen; Rao Yalamanchili

doi:10.1117/12.2680780

29 September 2023 Exploring photomask etching capabilities for new extreme ultraviolet absorber materials

Rebecca D. Stern, Jeff Chen, Rao Yalamanchili

Proceedings Volume 12915, Photomask Japan 2023: XXIX Symposium on Photomask and Next-Generation Lithography Mask Technology; 129150A (2023) https://doi.org/10.1117/12.2680780
Event: Photomask Japan 2023, 2023, Online Only

Abstract

As semiconductor device fabrication moves towards 2 nm technology nodes with EUV lithography, new EUV absorber materials will be needed to replace the current Ta-based EUV photomasks. The industry is looking for new absorber materials with a low refractive index (n) and a high extinction coefficient (k), to produce an attenuated phase-shift EUV photomask capable of minimizing 3D effects. The challenge is that these new materials are often difficult to etch. To identify the etching pathway for new EUV material candidates, this paper proposes the approach of thermodynamic characterization for various chemistries as etching byproducts. The Gibbs free energy of formation for these compounds can be collected at standard state conditions, so the potential for such chemical reactions can be evaluated. Meanwhile, the volatility of these reaction products can be estimated by the respective boiling points, which can be calculated from respective heats of vaporization at reduced pressures typically found in a plasma etch chamber. Collectively, this information can help to screen for new low-n / high-k absorber materials, to focus the selection only to candidates with potential etching feasibilities.

Citation Download Citation

Rebecca D. Stern, Jeff Chen, and Rao Yalamanchili "Exploring photomask etching capabilities for new extreme ultraviolet absorber materials", Proc. SPIE 12915, Photomask Japan 2023: XXIX Symposium on Photomask and Next-Generation Lithography Mask Technology, 129150A (29 September 2023); https://doi.org/10.1117/12.2680780

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
18 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Chemistry

Chemical elements

Etching

Extreme ultraviolet

Photomasks

Plasma

Refractive index

Show All Keywords

Keywords/Phrases

Search In:

Publication Years