Morphology of single picosecond pulse subsurface laser-induced modifications of sapphire and subsequent selective etching

Results of the work in the Laser4Fun project has been published as:

L. Capuano, R. Pohl, R. M. Tiggelaar, J. W. Berenschot, J. G. E. Gardeniers, and G. R. B. E. Römer, “Morphology of single picosecond pulse subsurface laser-induced modifications of sapphire and subsequent selective etching” Opt. Express26, 29283-29295 (2018)

Abstract

The effect of 1030nm single picosecond pulsed laser-induced modification of the bulk of crystalline sapphire using a combined process of laser amorphization and selective wet chemical etching is studied. Pulse durations of more than 1 picosecond are not commonly used for this subsurface process. We examine the effect of 7 picosecond pulses on the morphology of the unetched, as well as etched, single pulse modifications, showing the variation of shape and size when varying the pulse energy and the depth of processing. In addition, a qualitative analysis of the material transformation after irradiation is provided as well as an analysis of cracking phenomena. Finally, a calculated laser intensity profile inside sapphire, using the Point Spread Function (PSF), is compared to the shape of the modifications. This comparison is employed to calculate the intensity threshold leading to amorphization, which equals 2.5⋅1014 ± 0.4⋅1014 W/cm2.

Links:

DOI: 10.1364/OE.26.029283

Laser-Induced Periodic Surface Structures (LIPSS) on Polymers Processed with Picosecond Laser Pulses

Results of the work in the Laser4Fun project has been published as:

Marek Mezera, Martin van Drongelen and G.R.B.E. Römer. Laser-Induced Periodic Surface Structures (LIPSS) on Polymers Processed with Picosecond Laser Pulses, Journal of Laser Micro/Nanoengineering  Vol. 13, No. 2, 2018; doi: 10.2961/jlmn.2018.02.0010

Abstract

Based on a literature review, it was concluded that Laser-induced Periodic Surface Structures (LIPSS) on polymers are produced when applying laser sources operating either in the ultraviolet wavelength and nanosecond pulse duration, or radiation of wavelengths ranging from 265nm to 1045nm and pulse durations in the femtosecond regime. LIPSS were not reported when using pico-second laser sources. The purpose of this paper is to study whether (and if so which) LIPSS form on polymers when picosecond pulsed laser source is applied. Low Spatial Frequency LIPSS (LSFL) and High Spatial Frequency LIPSS (HSFL) have been obtained on polycarbonate and on polystyrene when applying picosecond laser pulses at a wavelength of 343nm on single spots and on processed lines. When using a wavelength of 515nm, LSFL and HSFL have been produced only on polycar-bonate, but also led to porosity of the structured area.

Links:

DOI: 10.2961/jlmn.2018.02.0010

Annual Technical Board and Supervisory Board Meeting in Bari, Italy (2018)

The 2018 Technical Board (TB) meeting and Supervisory Board (SB) meeting of the Laser4Fun project took place on October 4 and 5 in Bari, Italy. The meeting was hosted by prof. Antonio Ancona of IFN-CNR, Istituto di Fotonica e Nanotecnologie, Bari, Italy. The TB & SB discussed the progress of the project, results, management and reporting issues, as well as communication and dissemination topics. Also all Early Stage Researchers (ESRs) presented their progress and results to the SB. We were happy to conclude the project is well on track.

Technical Board (TB) meeting and Supervisory Board (SB) and all ESRs during the annual progress meeting in Bari, Italy.
Technical Board (TB) and Supervisory Board (SB) and all ESRs during the annual progress meeting in Bari, Italy.

Summer School on Laser Micro/Nanostructuring and Surface Tribology 2018

The 3rd Laser4Fun international Summer School took place from October 1st to 5th and was hosted by prof. Antonio Ancona of the IFN-CNR, Istituto di Fotonica e Nanotecnologie in Bari, Italy. The participants of the summer school were “fully-immersed” into the world of Laser Micro/Nanostructuring and Surface Tribology. Lectures and presentations by academic experts and of the participants alternated, with ample time for discussions. Topics included, but were not limited to:

  • Contact mechanics of elastic bodies, by dr. Ing. Carmine Putignano (Politecnico di Bari, Department of Mechanics, Mathematics and Management)
  • Universal lab-on-a-chip platform for complex, perfused 3D tissues generated by 3D printing – opportunities and perspectives for laser technology, by dr. Ing. Udo Klotzbach (Fraunhofer-Institut Material and Beam Technology IWS Dresden, Business Unit Manager Microtechnology)
  • Management of innovative project at Bosch: LST case study, by ing. Antonio Grimaldi and Ing. Renato Giannoccaro (Robert Bosch Group – Centro Studi Componenti per Veicoli s.p.a)
  • Cross Cultural Competences through cooperation and autonomy. Learning organization: higher education management and research administration, by dr.ssa Mariapia Circella (Physics Department, University of Bari)
  • Femtosecond laser micro-fabrication of polymeric lab-on-chip for advanced and mini-invasive diagnostics, by Udith K. Vadakkum Vadukkal (University of Bari, Italy)
  • Femtosecond laser bursts induced micro and nanostructuring on steel surface, by Giuseppe Giannuzzi (Università di Bari, Italy)
  • Contact mechanics of viscoelastic bodies, by prof. Ing. Giuseppe Carbone (PoliBa- Department of Mechanics, Mathematics and Management)
  • University of 21st century: threats and opportunities. Organizational chart: practical experiences, by dr.ssa Mariapia Circella (Physics Department, University of Bari)
Prticipants of the international School on Laser Micro/Nanostructuring and Surface Tribology 1st-5th October 2018, Bari, Italy
Prticipants of the international School on Laser Micro/Nanostructuring and Surface Tribology
1st-5th October 2018, Bari, Italy