During the past two decades, ultrafast lasers have been widely employed for high accuracy and high resolution micromachining purposes including both high precision surface micromachining and 3D internal structuring. Due to the ultrashort timescale and the ultrahigh laser intensity coupled to the electronic system, nonlinear absorption induces just at the focus point leading to highly localised material ablation or modification, thus assuring high processing accuracy and cleanness.
Recently, non-conventional beams such as Bessel beams have been used for in-bulk micromachining of various crystals. In contrast to conventional Gaussian beams, finite energy Bessel beams have the advantage of a long focal length, the so-called Bessel zone, orders of magnitude larger than the typical Rayleigh range for a given spot size, thanks to its quasi-non-diffracting nature. This leads to the possibility of fabricating high aspect-ratio microstructures in different materials without the need for sample translation. At the same time, due to their self-reconstruction property and their elongated focal zone, finite energy Bessel beams are ideal not only for internal micro structuring but also for high-impact technological applications.
The research activity on beam shaping and application to micromachining led by Dr. O. Jedrkiewicz is performed at the unit of Como (Insubria Univeristy, detached unit of IFN-CNR of Milano). The study and use of Bessel beams for the micromachining of transparent materials targets different applications such as:
- Cutting, drilling and etching of transparent materials
- Deep surface texturing on oxide semiconductors devices for photonic and gas sensing applications
- Generation of microfluidics components in Diamond
- Generation of Graphitic conductive microelectrodes in Diamond
Ongoing project
Bilateral project CNR-RS (UK), «Laser-patterned diamond superconducting single-photon sensors», (PI O. Jedrkiewicz)
Collaboration in the projects:
ITN Horizon2020 «LasIonDef» project (PI Shane M. Eaton, IFN Milano)
FISR project Fabbricazione intelligente di dispositivi QUANTistici in DIAmante mediante irraggiamento laser e impiantazione ionica (PI Shane M. Eaton, IFN Milano)
