The elongation of spherical Au nanoparticles embedded in [Formula: see text] under swift heavy ion (SHI) irradiation is an extensively studied phenomenon. The use of a TEM grid as a substrate facilitates the identification of the same nanoparticle before and after the irradiation. Since the underdensification of [Formula: see text] inside the ion track plays a key role, the elongation is sensitive to the matrix material properties. Therefore, we studied the elongation process of SHI irradiated Au spherical nanoparticles of various diameters (5–80 nm) embedded either in atomic layer deposition (ALD) or plasma-enhanced chemical vapor deposition (PECVD) [Formula: see text]. The results show that a different elongation ratio is achieved depending on the particle initial size, ion fluence, and a different [Formula: see text] deposition method. The embedded nanoparticles in ALD [Formula: see text] elongate roughly 100% more than the nanoparticles embedded in PECVD [Formula: see text] at the biggest applied fluence ([Formula: see text]). On the other hand, at fluences lower than [Formula: see text], nanoparticles elongate slightly more when they are embedded in PECVD [Formula: see text].

Highly energetic ions have been previously used to modify the shape of metal nanoparticles embedded in an insulating matrix. In this work, we demonstrate that under suitable conditions, energetic ions can be used not only for shape modification but also for manipulation of nanorod orientation. This observation is made by imaging the same nanorod before and after swift heavy ion irradiation using a transmission electron microscope. Atomistic simulations reveal a complex mechanism of nanorod re-orientation by an incremental change in its shape from a rod to a spheroid and further back into a rod aligned with the beam.

Metal oxide semiconductor capacitors that incorporate tantalum pentoxide (Ta2O5) thin films as dielectric were fabricated via the atomic layer deposition (ALD) technique and characterized through TEM, XPS, C–V, and I–V measurements. TEM analysis revealed the amorphous phase of Ta2O5 films and the existence of an ultrathin SiOx layer in the Ta2O5/p-Si interface, also evidenced by XPS spectra. XPS analysis verified the stoichiometry of the ALD-deposited Ta2O5 films. Furthermore, XPS results indicate values of 2.5 and 0.7 eV for the conduction and valence band offsets of the Ta2O5/p-Si interface, respectively. I–V measurements, for positive and negative applied bias voltages, reveal that the conduction is governed by Ohmic, trap controlled space charge limited, and Schottky mechanisms depending on the applied voltage and temperature region. Through the analysis of Schottky emission data, the conduction band offset of Ta2O5/p-Si (φΒ) is calculated to be 0.6 eV, while the valence band offset is 2.6 eV, in very good agreement with the XPS results. The energy band diagram of Ta2O5/p-Si is constructed.

Shape modification of embedded nanoparticles by swift heavy ion (SHI) irradiation is an effective way to produce nanostructures with controlled size, shape, and orientation.