Structural Evolution and Photoluminescence of SiO₂ Layers with Sn Nanoclusters Formed by Ion Implantation

Abstract

Samples of SiO2 (600 nm)/Si have been implanted with Sn ions (200 keV, 5×1016 cm−2 and 1×1017 cm−2) at room temperature and afterwards annealed at 800 and 900°C for 60 minutes in ambient air. The structural and light emission properties of “SiO2+Sn-based nanocluster” composites have been studied using Rutherford backscattering spectroscopy, transmission electron microscopy in cross section and plan-view geometry, electron microdiffraction, and photoluminescence (PL). A strict correspondence of Sn concentration profiles and depth particle distributions has been found. In the case of 1×1017 cm−2 fluence, the impurity accumulation in the subsurface zone during the thermal treatment leads to swelling and to the formation of dendrites composed of large and coalesced nanoparticles of grey contrast. The appearance of dendrites is most probably due to the SnO2 phase formation. The as-implanted samples are characterized by a weak emission with maximum at the blue range (2.9 eV). The PL intensity increases by an order of magnitude after annealing in an oxidizing atmosphere. The narrowest and most intense PL band has maximum at 3.1 eV. Its intensity increases with increasing fluence and annealing temperature. This emission can be attributed to the formation of the SnO2 phase (in the form of separate clusters or shells of Sn clusters) in the subsurface region of the SiO2 matrix.

Ion-Beam Synthesis of Gallium Oxide Nanocrystals in a SiO2/Si Dielectric Matrix

“…Ion-synthesized nanoinclusions of semiconductors such as Si [ 22 ], Sn [ 23 ], ZnO [ 24 ], In 2 O 3 [ 25 ] and many others have been previously reported. However, the ion synthesis of nc-Ga 2 O 3 was practically not reported, except in the case of our work, which demonstrated the possibility of synthesizing such nanocrystals in an Al 2 O 3 matrix [ 26 ].…”

Identification of paramagnetic centers in irradiated Sn-doped silicon dioxide by first-principles

“…As compared to the case of the Si-FO [58,68], the structure of the Sn-FO configurations is quite strained and at first sight considerably more similar to the one of a twofold coordinated Si/Ge atom [33]. The difference between Si-FO and Sn-FO structures is especially evident when looking to the O [3] -Sn and O [3] -Si bond distances formed by the three-fold coordinated oxygen (O [3] ): in the Sn-FO structure, the latter O [3] -Si distances are slightly longer (∼1.75 Å) than usual Si-O bond in silica (1.6 Å), while the former O [3] -Sn distance is remarkably longer (∼2.3 Å). By contrast for the Si-FO structure all the O [3] -Si bond distances are ∼1.8 Å [58].…”

“…Ion implantation is a largely exploited experimental way to introduce point defects in a solid matrix so to functionalize the host material [1]. For instance, Sn implantation of silica constitutes a way to make silica glass a luminescent material that can be interesting for optoelectronic or even photonic applications [2][3][4]. Moreover, Sn-doped silica glass has recently been proved to work as a dosimetric material based on the photoluminescence of Sn point defects [5].…”

“…Besides the 4.9 eV absorption band, twofold Sn centers in silica glass, and in other glasses, are responsible for singlet-singlet and triplet-singlet emissions at ∼4.2 eV and ∼3.1 eV which currently make them interesting for luminescence applications [3,5,[23][24][25][26][27]]. Yet, it is not so clear what kind of paramagnetic centers could be generated in irradiated Sn-doped silica containing twofold Sn centers [28].…”

Plasmonic Nanoparticles in Dielectrics Synthesized by Ion Beams: Optical Properties and Photonic Applications

“…[ 103 ] Recently, a number of literature have been published on the formation of hollow NPs and synthesis of core–shell NPs by one‐ or two‐step ion implantation. [ 104,106–118 ] In addition, specific nuclei‐shell structures such as multilayer NPs can also be synthesized by ion implantation in the simple operating steps. Ren et al performed the fabrication of sandwiched structure of NPs (i.e., Ag shell–nanovoid‐Ag core NPs) by one‐step ion implantation with Ag fluence as high as 2 × 10 17 ions cm −2 , as depicted in Figure .…”