Laser-plasma EUV source dedicated for surface processing of polymers

abstract In this work, a 10 Hz laser-plasma extreme ultraviolet (EUV) source built for surface processing ofpolymers is presented. The source is based on a double-stream gas puff target created in a vacuumchamber synchronously with the pumping laser pulse. The target is formed by pulsed injection of Kr, Xeor a KrXe gas mixture into a hollow stream of helium. The EUV radiation is focused using a grazingincidence gold-plated ellipsoidal collector. Spectrum of the reflected radiation consists of a narrowfeature with intensity maximum at 10–11 nm wavelength and a long-wavelength spectral tail up to70 nm. The exact spectral distribution depends on a gas applied for plasma creation. To avoid strongabsorption of the EUV radiation in a residual gas present in the chamber during the source operation atwo step differential pumping system was employed. The system allows for polymer processing underrelatively high vacuum conditions (10 5 mbar) or in a reactive gas atmosphere. Polymer samples canbe irradiated in a focal plane of the EUV collector or at some distance downstream the focal plane. Thisway fluence of the EUV beam at the polymer surface can be regulated.& 2011 Elsevier B.V. All rights reserved.

[1]  D. Nakamura,et al.  Investigation of debris dynamics from laser-produced tin plasma for EUV lithography light source , 2008 .

[2]  A. Bartnik,et al.  Physical and chemical modifications of PET surface using a laser-plasma EUV source , 2010 .

[3]  Randall L. Headrick,et al.  Self-assembled and etched cones on laser ablated polymer surfaces , 2006 .

[4]  Armin Bayer,et al.  Damage threshold measurements on EUV optics using focused radiation from a table-top laser produced plasma source. , 2010, Optics express.

[5]  Andrzej Bartnik,et al.  Ablation and surface modifications of PMMA using a laser-plasma EUV source , 2009 .

[6]  Chiew-seng Koay,et al.  Debris studies for the tin-based droplet laser-plasma EUV source , 2004, SPIE Advanced Lithography.

[7]  Andrzej Bartnik,et al.  Sub-70 nm resolution tabletop microscopy at 13.8 nm using a compact laser-plasma EUV source. , 2010, Optics letters.

[8]  S. Ellwi,et al.  In-band EUV radiation of ablative capillary discharges in PVC , 2003 .

[9]  Eric Robert,et al.  A novel fast capillary discharge system emitting intense EUV radiation: possible source for EUV lithography , 2003 .

[10]  M. Jaworski,et al.  Origins of debris and mitigation through a secondary RF plasma system for discharge-produced EUV sources , 2005 .

[11]  Hiroki Tanaka,et al.  Comparative study on emission characteristics of extreme ultraviolet radiation from CO2 and Nd:YAG laser-produced tin plasmas , 2005 .

[12]  Michael Olbrich,et al.  Cell microarrays on photochemically modified polytetrafluoroethylene. , 2005, Biomaterials.

[13]  Andrzej Bartnik,et al.  PMMA and FEP surface modifications induced with EUV pulses in two selected wavelength ranges , 2009 .

[14]  A. Bartnik,et al.  EUV micropatterning for biocompatibility control of PET , 2010 .

[15]  Libor Juha,et al.  Strong temperature effect on X-ray photo-etching of polytetrafluoroethylene using a 10 Hz laser-plasma radiation source based on a gas puff target , 2006 .

[16]  Libor Juha,et al.  Micromachining of organic polymers by X-ray photo-etching using a 10Hz laser-plasma radiation source , 2005 .

[17]  Sebastian Kranzusch,et al.  Spectral characterization of EUV radiation emitted from a laser-irradiated gas puff target , 2001 .

[18]  F. Leisch,et al.  Adhesion and proliferation of human endothelial cells on photochemically modified polytetrafluoroethylene. , 2003, Biomaterials.

[19]  R. Srinivasan,et al.  Surface properties of poly(ethylene terephthalate) films modified by far-ultraviolet radiation at 193nm (laser) and 185nm (low intensity) , 1986 .

[20]  Bjoern A. M. Hansson,et al.  A liquid-xenon-jet laser-plasma x-ray and EUV source , 2000 .

[21]  T. Lippert.  Laser application of polymers , 2004 .

[22]  Hans M. Hertz,et al.  Liquid-tin-jet laser-plasma extreme ultraviolet generation , 2004 .

[23]  Andrzej Bartnik,et al.  Compact laser plasma EUV source based on a gas puff target for metrology applications , 2005 .

[24]  Andrzej Bartnik,et al.  Strong extreme ultraviolet emission from a double-stream xenon/helium gas puff target irradiated with a Nd:YAG laser , 2000 .

[25]  Martin Richardson,et al.  Studies of high-repetition-rate laser plasma EUV sources from droplet targets , 2003 .

[26]  A. Bartnik,et al.  Characterization and optimization of the laser-produced plasma EUV source at 13.5 nm based on a double-stream Xe/He gas puff target , 2010 .