Synchrotron Radiation Direct Photo Etching of Polymers

Zhang, Y.

doi:10.1007/b12684

Cited by 17 publications

(7 citation statements)

References 77 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore its radiation-chemical and radiation-physical properties have been extensively studied and nowadays they are well understood over a wide range of irradiation conditions. PMMA erosion induced by high-energy photons (often also called direct photoinduced PMMA etching) in vacuum has already been investigated with synchrotron radiation [3,4] and with incoherent XUV/X-ray radiation from plasma-based sources [5,6]. Earlier studies [7][8][9] in the XUV laser-induced ablation of PMMA showed that the process is very clean.…”

Section: Introductionmentioning

confidence: 99%

Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids

Chalupský¹,

Juha²,

Kuba³

et al. 2007

Opt. Express

102

View full text Add to dashboard Cite

A linear accelerator based source of coherent radiation, FLASH (Free-electron LASer in Hamburg) provides ultra-intense femtosecond radiation pulses at wavelengths from the extreme ultraviolet (XUV; lambda<100nm) to the soft X-ray (SXR; lambda<30nm) spectral regions. 25-fs pulses of 32-nm FLASH radiation were used to determine the ablation parameters of PMMA - poly (methyl methacrylate). Under these irradiation conditions the attenuation length and ablation threshold were found to be (56.9+/-7.5) nm and approximately 2 mJ*cm(-2), respectively. For a second wavelength of 21.7 nm, the PMMA ablation was utilized to image the transverse intensity distribution within the focused beam at mum resolution by a method developed here.

show abstract

Section: Introductionmentioning

confidence: 99%

Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids

Chalupský¹,

Juha²,

Kuba³

et al. 2007

Opt. Express

102

View full text Add to dashboard Cite

show abstract

“…However, thermal graphitization cannot follow HH irradiation because the surface temperature is too low even if 100% of the radiation energy would be absorbed and thermalized in the near-surface layer. Single-photon damage to material structure can occur there, as suggested by Deacon [12], and was demonstrated with synchrotron radiation as photo-induced material removal [13,14] as well as sample expansion [14].…”

Section: Resultsmentioning

confidence: 96%

Radiation damages to amorphous-carbon optical coatings

Juha¹,

Bittner

Grazia

et al. 2005

SPIE Proceedings

View full text Add to dashboard Cite

The multi-mJ, 21-nm soft-x-ray laser at the PALS facility was focused onto the surfaces of amorphous carbon (a-C) coatings, developed for heavily loaded XUV/x-ray optical elements. AFM (Atomic Force Microscopy) images show a 3-micrometer expansion of the irradiated material. Raman spectra, measured with an Ar + laser microbeam in both irradiated and unirradiated areas, confirm a high degree of graphitization in the irradiated layer. In addition to this highfluence (~ 1 J/cm 2 ), single-shot experiment, it was necessary to carry out an experiment to investigate the consequences of prolonged XUV irradiation at relatively low fluence. A high-order harmonic (HH) beam generated at the LUCA facility of the CEA/Saclay Research Center was used as a source of short-wavelength radiation delivering high-energy photons to the surfaces at a low single-shot fluence but with high-average power. a-C irradiated at low fluence, (< 0.1 mJ/cm 2 ) by many HH shots exhibits an expansion of several nanometers. Although it is a less dramatic change of surface morphology than that due to single-shot x-ray-laser exposures, even the observed nanometer-sized changes caused on an a-C surface by an HH beam could influence the reflectivity of a grazing incidence optical element. These results seem to be important for estimating damage to surfaces of highly irradiated optical elements developed for guiding and focusing the ultra-intense XUV/x-ray beams provided by the new generation of sources (VUV FEL and XFEL in Hamburg; LCLS in Stanford) because, up to now, only melting and vaporization, and not graphitization, have been taken into account.

show abstract

“…For instance, polarized NEXAFS studies of polyethylene and fluorinated polyethylenes were already studied by Ohta et al in 1990 . Surface modification of poly(tetrafluoroethylene) (PTFE) by SR exposure has been the subject of many publications in the past, − including studies using several kinds of gas atmospheres to investigate the chemical changes after irradiation . Okudaira et al investigated the photodegradation of PTFE and poly(vinylidene fluoride) (PVDF) thin films by inner shell excitation .…”

Section: Introductionmentioning

confidence: 99%

Selective Fragmentation of Radiation-Sensitive Novel Polymeric Resist Materials by Inner-Shell Irradiation

Chagas

Satyanarayana

Kessler

et al. 2015

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Two key concepts in extreme ultraviolet lithography (EUVL) are important for it to be a candidate for the mass production of future integrated circuits: the polymer formulation and the photofragmentation process. In this work, both concepts were carefully studied. The design and synthesis of radiation-sensitive organic polymeric materials based on the inclusion of a radiation-sensitive tetrahydrothiophenium functional group are outlined. A 1-(4-methacryloyoxy)naphthalene-1-yl)tetrahydro-1H-thiophenium trifluoromethanesulfonate (MANTMS) monomer containing the tetrahydrothiophenium group undergoes homo- and copolymerizations using free-radical polymerization with a 2,2'-azobis(isobutyronitrile) initiator. The surface photodegradation and oxidation of these novel polymeric materials were investigated using highly monochromatized soft X-rays from synchrotron radiation at the carbon K-edge excitation region. An efficient functionalization was observed when the excitation energy was tuned to C 1s → π*C═C. A high rate of defluorination and a loss of sulfonated groups as a result of an increase in the irradiation time for the MANTMS homopolymer thin films were mainly observed under the π*C═C excitation of the naphthyl functional groups. On the contrary, excitation similar to C 1s → π*C═O or C 1s → σ*C-F did not produce important degradation, showing a highly selective process of bond breaking. Additionally, the presence of methyl methacrylate copolymer in the original MANTMS yielded a much higher degree of stability against inner-shell radiation damage. Our results highlight the importance of choosing the right polymer formulation and excitation energy to produce a sensitive material for EUVL without using the concept of chemical amplification.

show abstract

Synchrotron Radiation Direct Photo Etching of Polymers

Cited by 17 publications

References 77 publications

Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids

Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids

Radiation damages to amorphous-carbon optical coatings

Selective Fragmentation of Radiation-Sensitive Novel Polymeric Resist Materials by Inner-Shell Irradiation

Contact Info

Product

Resources

About