Introducing a Dynamic Reconstruction Methodology for Multilayered Structures in Atom Probe Tomography.

Atom probe tomography (APT) is a powerful three-dimensional nanoanalyzing microscopy technique considered key in modern materials science. However, progress in the spatial reconstruction of APT data has been rather limited since the first implementation of the protocol proposed by Bas et al. in 1995.

Hyperdoped Si nanocrystals embedded in silica for infrared plasmonics.

We present the experimental realization of plasmonic hyperdoped Si nanocrystals embedded in silica a combination of sequential low energy ion implantation and rapid thermal annealing. We show that phosphorus dopants are incorporated into the nanocrystal cores at concentrations up to six times higher than P solid solubility in bulk Si by combining 3D mapping with atom probe tomography and analytical transmission electron microscopy. We shed light on the origin of nanocrystal growth at high P doses, which we attribute to Si recoiling atoms generated in the matrix by P implantation, which likely increase Si diffusivity and feed the Si nanocrystals.

Infrared nanoplasmonic properties of hyperdoped embedded Si nanocrystals in the few electrons regime.

Using localized surface plasmon resonance (LSPR) as an optical probe we demonstrate the presence of free carriers in phosphorus doped silicon nanocrystals (SiNCs) embedded in a silica matrix. In small SiNCs, with radius ranging from 2.6 to 5.

Influence of phosphorus on the growth and the photoluminescence properties of Si-NCs formed in P-doped SiO/SiO multilayers.

This work reports on the influence of phosphorous atoms on the phase separation process and optical properties of silicon nanocrystals (Si-NCs) embedded in phosphorus doped SiO/SiO multilayers. Doped SiO/SiO multilayers with different P contents have been prepared by co-evaporation and subsequently annealed at different temperatures up to 1100 °C. The sample structure and the localization of P atoms were both studied at the nanoscale by scanning transmission electron microscopy and atom probe tomography.

Simultaneous quantification of indium and nitrogen concentration in InGaNAs using HAADF-STEM.

To unambiguously evaluate the indium and nitrogen concentrations in In(x)Ga(1-x)N(y)As(1-y), two independent sources of information must be obtained experimentally. Based on high-resolution scanning transmission electron microscopy (STEM) images taken with a high-angle annular dark-field (HAADF) detector the strain state of the InGaNAs quantum well is determined as well as its characteristic HAADF-scattering intensity. The strain state is evaluated by applying elasticity theory and the HAADF intensity is used for a comparison with multislice simulations.

Nanoscale evidence of erbium clustering in Er-doped silicon-rich silica.

: Photoluminescence spectroscopy and atom probe tomography were used to explore the optical activity and microstructure of Er3+-doped Si-rich SiO2 thin films fabricated by radio-frequency magnetron sputtering. The effect of post-fabrication annealing treatment on the properties of the films was investigated. The evolution of the nanoscale structure upon an annealing treatment was found to control the interrelation between the radiative recombination of the carriers via Si clusters and via 4f shell transitions in Er3+ ions.

Atomic scale investigation of silicon nanowires and nanoclusters.

In this study, we have performed nanoscale characterization of Si-clusters and Si-nanowires with a laser-assisted tomographic atom probe. Intrinsic and p-type silicon nanowires (SiNWs) are elaborated by chemical vapor deposition method using gold as catalyst, silane as silicon precursor, and diborane as dopant reactant. The concentration and distribution of impurity (gold) and dopant (boron) in SiNW are investigated and discussed.

Atomic characterization of Si nanoclusters embedded in SiO2 by atom probe tomography.

Silicon nanoclusters are of prime interest for new generation of optoelectronic and microelectronics components. Physical properties (light emission, carrier storage..

Evidence of superparamagnetic co clusters in pulsed laser deposition-grown Zn0.9Co0.1O thin films using atom probe tomography.

Nanosized Co clusters (of about 3 nm size) were unambiguously identified in Co-doped ZnO thin films by atom probe tomography. These clusters are directly correlated to the superparamagnetic relaxation observed by ZFC/FC magnetization measurements. These analyses provide strong evidence that the room-temperature ferromagnetism observed in the magnetization curves cannot be attributed to the observed Co clusters.