Vol.:(0123456789) 1 3 Applied Physics A (2020) 126:404 https://doi.org/10.1007/s00339-020-03538-x S.I.: CURRENT STATE-OF-THE-ART IN LASER ABLATION 10 B‑based flms grown by pulsed laser deposition for neutron conversion applications Maura Cesaria 1  · Antonella Lorusso 1,2  · Anna Paola Caricato 1,2  · Paolo Finocchiaro 3  · Simone Amaducci 3,4  · Maurizio Martino 1,2  · Muhammad Rizwan Aziz 1  · Lucio Calcagnile 2,5  · Alessio Perrone 1,2  · Gianluca Quarta 2,5 Received: 9 October 2019 / Accepted: 9 April 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020 Abstract Solid-state neutron detectors exploit nuclear interactions producing energetic charged particles within a converter layer embedding nuclei with high neutron capture cross section and with thickness compatible with the charged particle range. Recently, boron-10 ( 10 B) is being considered as a valid alternative to the expensive and decreasingly available 3 He gas thanks to its large neutron absorption cross section and high-energy reaction products. Minimized amounts of impurities, flms with optimal and well-controlled thickness, good uniformity over large areas and good adhesion to the substrates are essential to achieve efcient neutron detection performance. In this study, we present well-adherent 1-µm-thick 10 B-enriched boron coatings, deposited over a large area by of-axis pulsed laser deposition (PLD) using a nanosecond Nd-YAG laser beam oper- ating at 1064 nm and high fuence (~ 10 J/cm 2 ), onto 1-mm-thick Al substrate as well as smooth and rough C substrates. By combining plasma plume divergence and peaked profle under of-axis deposition geometry, uniform 10 B flms were obtained over an area of a 3.4 × 3.4 cm 2 . We discuss the morphological characteristics of our deposits as related to the mechanisms of nanosecond laser ablation and present energy dispersive spectroscopy (EDS) elemental analysis of the flm, paying atten- tion to the diferent surface features. Negligible presence of O, N and C contaminants was achieved by controlled vacuum conditions. Moreover, we present encouraging neutron detection performances of our flm deposited onto Al. Keywords Solid neutron-to-charge converter · Boron coatings · Pulsed laser deposition · Boron enrichment · Textured substrate 1 Introduction Early studies of boron (B) date back to two centuries ago and point out the ability of boron to combine with almost any element to form compounds [1]. The frst report on pure boron in 1957 [2] documented a very complex structure which is nowadays known to have the most varied poly- morphs (at least sixteen) including interlinked B 12 icosa- hedra structural units arranged/linked in diferent lattice architectures [3, 4]. Boron and boron compounds have outstanding physi- cal properties, such as high hardness (comparable to dia- mond), high stability of B–B bonds, corrosion resistance, low densities, high melting temperatures, high refectance in the extreme ultraviolet (40–200 nm), as well as tunable thermal and electric transport properties depending on the dimensionality (thin flms, nanowires, boron fullerene (B 40 molecules), borophene (graphene-like structures composed of boron atoms) [5–8]. It results in a large number of appli- cation areas that make up the elemental boron and boron- based materials of scientifc and technological interest. For instance, elemental boron flms can be used in thermoelec- tric energy conversion devices operating at high tempera- tures [9], as protective coatings and biomedical implants * Anna Paola Caricato annapaola.caricato@unisalento.it 1 Department of Mathematics and Physics “Ennio De Giorgi”, University of Salento, Lecce, Italy 2 National Institute of Nuclear Physics (INFN), Lecce, Italy 3 National Institute of Nuclear Physics (INFN) - Laboratori Nazionali del Sud, Catania, Italy 4 Department of Physics and Astronomy, University of Catania, Catania, Italy 5 Centre of Applied Physics, Dating and Diagnostics (CEDAD), Department of Mathematics and Physics “Ennio De Giorgi”, University of Salento, Lecce, Italy