Nanoparticle contamination is one of the crucial issues for the semiconductor industry on the move towards structure sizes of and below. In extreme ultraviolet lithography (EUVL), a likely successor to optical lithography, the masks cannot be protected by common pellicles. Different protection methods, such as a “thermophoretic pellicle” [L. Klebanoff and D. J. Rader, US Patent No. 6,153,044 (2000) and US Patent No. 6,253,464 B1 (2001)] have therefore been proposed to protect a face-down mask in an EUV scanner, which might be operated at . In order to quantify the effectiveness of such protection schemes, we developed an analytical model that allows simple determination of the particle stopping distance as a function of particle and gas properties as well as a thermal gradient that might be employed to make use of a thermophoretic force in order to protect the mask. The analytical results indicate that drag force is most effective in slowing down particles, traveling at high initial velocities. Thermophoresis can add effective protection to particles traveling at low velocities and therefore decrease diffusional deposition. The results from the analytical model were used to check the accuracy of the discrete phase model in FLUENT for particle diameters between 100 and and pressure levels between and (corresponding Knudsen numbers . The comparison results indicate that with no thermal gradient, the results agree very well with less than 2% deviation. If thermophoresis is included, the absolute deviation generally increases with increasing Knudsen number and with increasing temperature gradient. For a temperature gradient of and a Knudsen number of , the deviation reaches almost 50% for initial particle velocity.
Skip Nav Destination
,
,
,
,
Article navigation
November 2005
This content was originally published in
Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena
Research Article|
November 03 2005
Modeling of protection schemes for critical surfaces under low pressure conditions: Comparison between analytical and numerical approach
Christof Asbach;
Christof Asbach
Particle Technology Laboratory,
University of Minnesota
, Minneapolis, Minnesota 55455
Search for other works by this author on:
David Y. H. Pui;
David Y. H. Pui
a)
Particle Technology Laboratory,
University of Minnesota
, Minneapolis, Minnesota 55455
Search for other works by this author on:
Jung Hyeun Kim;
Jung Hyeun Kim
Particle Technology Laboratory,
University of Minnesota
, Minneapolis, Minnesota 55455
Search for other works by this author on:
Se-Jin Yook;
Se-Jin Yook
Particle Technology Laboratory,
University of Minnesota
, Minneapolis, Minnesota 55455
Search for other works by this author on:
Heinz Fissan
Heinz Fissan
Institute for Energy and Environmental Technology
, Duisburg, Germany
Search for other works by this author on:
Christof Asbach
David Y. H. Pui
a)
Jung Hyeun Kim
Se-Jin Yook
Heinz Fissan
Particle Technology Laboratory,
University of Minnesota
, Minneapolis, Minnesota 55455a)
Electronic mail: [email protected]
J. Vac. Sci. Technol. B 23, 2419–2426 (2005)
Article history
Received:
June 30 2005
Accepted:
September 19 2005
Citation
Christof Asbach, David Y. H. Pui, Jung Hyeun Kim, Se-Jin Yook, Heinz Fissan; Modeling of protection schemes for critical surfaces under low pressure conditions: Comparison between analytical and numerical approach. J. Vac. Sci. Technol. B 1 November 2005; 23 (6): 2419–2426. https://doi.org/10.1116/1.2122927
Download citation file:
Pay-Per-View Access
$40.00
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Citing articles via
Future of plasma etching for microelectronics: Challenges and opportunities
Gottlieb S. Oehrlein, Stephan M. Brandstadter, et al.
Transferable GeSn ribbon photodetectors for high-speed short-wave infrared photonic applications
Haochen Zhao, Suho Park, et al.
Exploring SiC CVD growth parameters compatible with remote epitaxy
Daniel J. Pennachio, Jenifer R. Hajzus, et al.
Related Content
Simple theoretic approach to estimate the effect of gravity and thermophoresis on the diffusional nanoparticle contamination under low pressure conditions
J. Vac. Sci. Technol. B (December 2006)
Investigation of thermophoretic protection with speed-controlled particles at 100, 50, and 25 mTorr
J. Vac. Sci. Technol. B (April 2006)
Verification studies of thermophoretic protection for extreme ultraviolet masks
J. Vac. Sci. Technol. B (January 2005)
Recent advance in protection technology for extreme ultraviolet lithography masks under low-pressure condition
J. Vac. Sci. Technol. B (January 2008)
Effect of reverse flow by differential pressure on the protection of critical surfaces against particle contamination
J. Vac. Sci. Technol. B (June 2006)