Share Email Print

Proceedings Paper

Damage and degradation of optics and sensors under intense EUV radiation from a table-top laser produced plasma source
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

In recent years, technological developments in the area of extreme ultraviolet lithography (EUVL) have experienced great improvements. Currently, the application of EUV radiation apart from microlithography comes more and more into focus. Main goal of our research is to utilize the unique interaction between soft x-ray radiation and matter for probing, modifying, and structuring solid surfaces. In this contribution we present a setup capable of generating and focusing EUV radiation. It consists of a table-top laser-produced plasma source. In order to obtain a small focal spot resulting in high EUV fluence, a modified Schwarzschild objective consisting of two spherical mirrors with Mo/Si multilayer coatings is adapted to this source, simultaneously blocking unwanted out-of-band radiation. By demagnified (10x) imaging of the plasma an EUV spot of 5 μm diameter with a maximum energy density of ~7.4 J/cm² is generated (pulse length 8.8 ns). We present first applications of this integrated source and optics system, demonstrating its potential for high-resolution modification and structuring of solid surfaces. As an example, etch rates for PMMA, PC and PTFE depending on EUV fluences were determined, indicating a linear etch behavior for lower energy densities. In order to investigate damage tests on EUV sensors and optics, 1-on-1 damage tests were performed on grazing incidence gold mirrors, Mo/Si multilayer mirrors and mirror substrates. To our knowledge, this is the first time that such experiments using nanosecond EUV-pulses were carried out.

Paper Details

Date Published: 31 December 2009
PDF: 10 pages
Proc. SPIE 7504, Laser-Induced Damage in Optical Materials: 2009, 75041J (31 December 2009); doi: 10.1117/12.837357
Show Author Affiliations
Frank Barkusky, Laser-Lab. Göttingen e.V. (Germany)
Armin Bayer, Laser-Lab. Göttingen e.V. (Germany)
Bernhard Flöter, Laser-Lab. Göttingen e.V. (Germany)
Christian Peth, Laser-Lab. Göttingen e.V. (Germany)
Klaus Mann, Laser-Lab. Göttingen e.V. (Germany)

Published in SPIE Proceedings Vol. 7504:
Laser-Induced Damage in Optical Materials: 2009
Gregory J. Exarhos; Vitaly E. Gruzdev; Detlev Ristau; M. J. Soileau; Christopher J. Stolz, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?