Multi-energy ion implantation from high-intensity laser

Abstract

Abstract. The laser-matter interaction using nominal laser intensity above 10 15 W/cm 2 generates in vacuum non--equilibrium plasmas accelerating ions at energies from tens keV up to hundreds MeV. From thin targets, using the TNSA regime, plasma is generated in the forward direction accelerating ions above 1 MeV per charge state and inducing high-ionization states. Generally, the ion energies follow a Boltzmann-like distribution characterized by a cutoff at high energy and by a Coulomb-shift towards high energy increasing the ion charge state. The accelerated ions are emitted with the high directivity, depending on the ion charge state and ion mass, along the normal to the target surface. The ion fl uencies depend on the ablated mass by laser, indeed it is low for thin targets. Ions accelerated from plasma can be implanted on different substrates such as Si crystals, glassy-carbon and polymers at different fl uences. The ion dose increment of implanted substrates is obtainable with repetitive laser shots and with repetitive plasma emissions. Ion beam analytical methods (IBA), such as Rutherford backscattering spectroscopy (RBS), elastic recoil detection analysis (ERDA) and proton-induced X-ray emission (PIXE) can be employed to analyse the implanted species in the substrates. Such analyses represent 'off-line' methods to extrapolate and to character the plasma ion stream emission as well as to investigate the chemical and physical modifi cations of the implanted surface. The multi-energy and species ion implantation from plasma, at high fl uency, changes the physical and chemical properties of the implanted substrates, in fact, many parameters, such as morphology, hardness, optical and mechanical properties, wetting ability and nanostructure generation may be modifi ed through the thermal-assisted implantation by multi-energy ions from laser-generated plasma.

Investigation of the effect of plasma waves excitation on target normal sheath ion acceleration using fs laser‐irradiating hydrogenated structures

“…TNSA can be employed to accelerate light ions at a high charge state, which can be used as a compact ion accelerator, in order to induce nuclear reactions for astrophysical and matter structure interest. Moreover, proton and helium beams accelerated in the TNSA regime can be employed for surface ion beam analysis and surface ion beam treatments . The accelerated ions can be used to irradiate secondary targets and to be implanted in order to modify their chemical and physical properties.…”

“…Moreover, proton and helium beams accelerated in the TNSA regime can be employed for surface ion beam analysis and surface ion beam treatments. [7] The accelerated ions can be used to irradiate secondary targets and to be implanted in order to modify their chemical and physical properties. TNSA can also be employed to accelerate and to extract from a punctual source relativistic electron beams or to generate high-intensity X-ray emission, which can be filtered in the region of soft or hard energy.…”

Ion Beam Analysis applied to laser-generated plasmas

“…Preliminary results show significant changes of the substrate roughness and wetting ability of the ion implanted surfaces with respect to the pristine ones [14].…”

Fabrication and characterization of porous opaque PMMA foils to be laser irradiated producing ion acceleration

“…Possible applications of such opaque PMMA with Au nanoparticles concern the proton acceleration for protontherapy [18], the proton and deuterium acceleration to induce nuclear reaction and fusion processes [19], the simulation of astrophysical environment, the use of ion beams for material treatments and the use of ion implantation to modify the chemical and physical properties of many elements [20].…”