Here we report a femtosecond laser direct writing(a precise 3D printing also known as two-photon polymerization lithography) of hybrid organic-inorganic SZ2080^(TM)pre-polymer without using any photo-initiator and app...Here we report a femtosecond laser direct writing(a precise 3D printing also known as two-photon polymerization lithography) of hybrid organic-inorganic SZ2080^(TM)pre-polymer without using any photo-initiator and applying ~100 fs oscillator operating at 517 nm wavelength and 76 MHz repetition rate. The proof of concept was experimentally demonstrated and benchmarking 3D woodpile nanostructures, micro-scaffolds, free-form micro-object “Benchy” and bulk micro-cubes are successfully produced. The essential novelty underlies the fact that non-amplified laser systems delivering just 40-500 p J individual pulses are sufficient for inducing localized cross-linking reactions within hundreds of nanometers in cross sections. And it is opposed to the prejudice that higher pulse energies and lower repetition rates of amplified lasers are necessary for structuring non-photosensitized polymers. The experimental work is of high importance for fundamental understanding of laser enabled nanoscale 3D additive manufacturing and widens technology’ s field of applications where the avoidance of photo-initiator is preferable or is even a necessity, such as micro-optics, nano-photonics, and biomedicine.展开更多
Laser direct writing employing multi-photon 3D polymerisation is a scientific and industrial tool used in various fields such as micro-optics,medicine,metamaterials,programmable materials,etc.,due to the fusion of hig...Laser direct writing employing multi-photon 3D polymerisation is a scientific and industrial tool used in various fields such as micro-optics,medicine,metamaterials,programmable materials,etc.,due to the fusion of highthroughput and fine features down to hundreds of nm.Some limitations of technology applicability emerge from photo-resin properties,however any material modifications can strongly affect its printability,as photoexcitation conditions alter as well.Here we present wavelength-independent 3D polymerisation using low peak power laser oscillators.High pulse repetition rate and fast laser direct writing was employed for advancing additive manufacturing out of the SZ2080^(TM)photo-resist without any photo-initiator.Wavelengths of 517 nm,780 nm,and 1035 nm are shown to be suitable for producing 300 nm polymerized features even at high-up to 10^(5)μm/s-writing speeds.Variation of organic-inorganic ratio in hybrid material results in shift and decrease of the dynamic fabrication window,yet not prohibiting the photo-structuring.Controlled energy deposition per focal volume is achieved due to localized heating enabling efficient 3D printing.Such spatio-selective photo-chemical crosslinking widens optical manufacturing capacity of non-photo-sensitive materials.展开更多
基金Project(S-MIP-20-17) supported by the Research Council of LithuaniaProject(871124) supported by the EU Horizon 2020, Research and Innovation program LASERLAB-EUROPE JRA。
文摘Here we report a femtosecond laser direct writing(a precise 3D printing also known as two-photon polymerization lithography) of hybrid organic-inorganic SZ2080^(TM)pre-polymer without using any photo-initiator and applying ~100 fs oscillator operating at 517 nm wavelength and 76 MHz repetition rate. The proof of concept was experimentally demonstrated and benchmarking 3D woodpile nanostructures, micro-scaffolds, free-form micro-object “Benchy” and bulk micro-cubes are successfully produced. The essential novelty underlies the fact that non-amplified laser systems delivering just 40-500 p J individual pulses are sufficient for inducing localized cross-linking reactions within hundreds of nanometers in cross sections. And it is opposed to the prejudice that higher pulse energies and lower repetition rates of amplified lasers are necessary for structuring non-photosensitized polymers. The experimental work is of high importance for fundamental understanding of laser enabled nanoscale 3D additive manufacturing and widens technology’ s field of applications where the avoidance of photo-initiator is preferable or is even a necessity, such as micro-optics, nano-photonics, and biomedicine.
基金funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101007417having benefited from the access provided by FORTH in Two-photon Lithography(TWL),Scanning Electron Microscopy(SEM),PhotoLuminescence(PL)within the framework of the NFFA-Europe Pilot Transnational Access Activity,proposal[ID-077].The research leading to these results has received funding from LASERLAB-EUROPE(grant agreement no.871124,European Union’s Horizon 2020 research and innovation programme)+2 种基金A.B.,E.S.and M.M acknowledge Vilnius University Excellence Initiative programme,and S.J.under Adjunct agreement as Visiting Professor for mutual research activities with the Laser Research Center of the Faculty of Physics of Vilnius UniversityFurthermore,part of this work was co-financed by Greece and the European Union(European Social Fund-ESF)through the Operational Programme“Human Resources Development,Education and Lifelong Learning”in the context of the Act“Enhancing Human Resources Research Potential by undertaking a Doctoral Research”Sub-action 2:IKY Scholarship Programme for Ph.D.candidates in the Greek UniversitiesThe research project was co-funded by the Stavros Niarchos Foundation(SNF)and the Hellenic Foundation for Research and Innovation(H.F.R.I.)under the 5th Call of“Science and Society”Action-“Always Strive for Excellence-Theodore Papazoglou”(Project Number:9578.)。
文摘Laser direct writing employing multi-photon 3D polymerisation is a scientific and industrial tool used in various fields such as micro-optics,medicine,metamaterials,programmable materials,etc.,due to the fusion of highthroughput and fine features down to hundreds of nm.Some limitations of technology applicability emerge from photo-resin properties,however any material modifications can strongly affect its printability,as photoexcitation conditions alter as well.Here we present wavelength-independent 3D polymerisation using low peak power laser oscillators.High pulse repetition rate and fast laser direct writing was employed for advancing additive manufacturing out of the SZ2080^(TM)photo-resist without any photo-initiator.Wavelengths of 517 nm,780 nm,and 1035 nm are shown to be suitable for producing 300 nm polymerized features even at high-up to 10^(5)μm/s-writing speeds.Variation of organic-inorganic ratio in hybrid material results in shift and decrease of the dynamic fabrication window,yet not prohibiting the photo-structuring.Controlled energy deposition per focal volume is achieved due to localized heating enabling efficient 3D printing.Such spatio-selective photo-chemical crosslinking widens optical manufacturing capacity of non-photo-sensitive materials.
