Share Email Print

Proceedings Paper

Verification studies of thermophoretic protection for EUV masks
Author(s): Daniel J. Rader; Daniel E. Dedrick; Eric W. Beyer; Alvin H. Leung; Leonard E. Klebanoff
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

A 'thermophoretic pellicle' has been proposed as an alternative to the traditional organic pellicle as a means of protecting EUV lithographic photomasks from particle contamination. The thermophoretic pellicle protects a mask from particles by exploiting the thermophoretic force, which is exerted on a particle by a surrounding gas in which a temperature gradient exists. Two critical requirements of the thermophoretic pellicle are: 1) the mask is kept warmer than its surroundings (either by heating the mask or by cooling the surroundings) and 2) the surrounding gas pressure is kept sufficiently high to enable thermophoretic protection. Experiments are presented which verify the viabilitiy of thermophoretic protection for EUV masks under model conditions. In these experiments, wafers are exposed to monodisperse polystyrene latex (PSL) spheres under carefully controlled experimental conditions. Robust thermophoretic protection is observed over a wide range of argon gas pressures (50-1600 mTorr or 6.66-213 Pa), particle sizes (65-300 nm), and temperature gradients (2-15 K/cm).

Paper Details

Date Published: 1 July 2002
PDF: 12 pages
Proc. SPIE 4688, Emerging Lithographic Technologies VI, (1 July 2002); doi: 10.1117/12.472288
Show Author Affiliations
Daniel J. Rader, Sandia National Labs. (United States)
Daniel E. Dedrick, Sandia National Labs. (United States)
Eric W. Beyer, Sandia National Labs. (United States)
Alvin H. Leung, Sandia National Labs. (United States)
Leonard E. Klebanoff, Sandia National Labs. (United States)

Published in SPIE Proceedings Vol. 4688:
Emerging Lithographic Technologies VI
Roxann L. Engelstad, Editor(s)

© SPIE. Terms of Use
Back to Top