Effects of the ratio of sphere size to laser focal spot on the dominant in-band EUV emitting region

Sam Yuspeh; Kevin L. Sequoia; Yezheng Tao; Mark S. Tillack; Russell A. Burdt; Farrokh Najmabadi

doi:10.1117/12.814167

18 March 2009 Effects of the ratio of sphere size to laser focal spot on the dominant in-band EUV emitting region

Sam Yuspeh, Kevin L. Sequoia, Yezheng Tao, Mark S. Tillack, Russell A. Burdt, Farrokh Najmabadi

Proceedings Volume 7271, Alternative Lithographic Technologies; 727136 (2009) https://doi.org/10.1117/12.814167
Event: SPIE Advanced Lithography, 2009, San Jose, California, United States

Abstract

Previous experiments on Nd:YAG laser produced Sn plasmas showed little dependence of the location of the dominant in-band extreme ultraviolet emitting region on target geometry. Modeling and experiments were preformed in order to better understand this phenomenon. A two-dimensional radiation hydrodynamic code, h2d, was benchmarked with experiments using Sn microspheres. Numerically obtained densities above the diagnostic limitation and temperature profile maps, which cannot be measured experimentally, were used to explain the effect, which comes from a relatively small change in the location of the critical density surface. This is important to EUV lithography because both the density and temperature play significant roles in the generation and transport of in-band EUV light. It is desired to have the highest possible density at the dominant emitting surface and the smallest possible surrounding plasma to produce high 13.5 nm conversion efficiency (2% bandwidth). The target geometry impacts the amount of lateral expansion leading to dramatically different density profiles and therefore can be optimized to meet these conditions.

Citation Download Citation

Sam Yuspeh, Kevin L. Sequoia, Yezheng Tao, Mark S. Tillack, Russell A. Burdt, and Farrokh Najmabadi "Effects of the ratio of sphere size to laser focal spot on the dominant in-band EUV emitting region", Proc. SPIE 7271, Alternative Lithographic Technologies, 727136 (18 March 2009); https://doi.org/10.1117/12.814167

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
8 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Plasmas

Extreme ultraviolet

Optical spheres

Absorption

Tin

Extreme ultraviolet lithography

Diagnostics

Show All Keywords

Keywords/Phrases

Search In:

Publication Years