This work reports experimental results of the quantitative determination of oxygen and band gap measurement in the TiN_x electrodes in planar TiN_x top/La:HfO₂/TiN_x bottom MIM stacks obtained by plasma enhanced atomic layer deposition on SiO₂. Methodological aspects of extracting structural and chemical information from (scanning) transmission electron microscopy imaging (bright field and high angular annular dark field), energy dispersive X-ray spectrometry and electron energy loss spectroscopy are thoroughly considered. The study shows that the oxygen concentration is higher in the TiN_xO_y bottom electrode (about 14.2 ± 0.1 at. %) compared to the TiN_xO_y top electrode (about 11.4 ± 0.5 at. %). The following average stoichiometric formulas are TiN₀.₅₂O₀.₂₀ top and TiN₀.₅₄O₀.₂₆ bottom for top and bottom electrodes, respectively. The amount of oxygen incorporated into TiN_x during PEALD because of oxygen impurities in the plasma is minor compared to that because of diffusion from SiO₂ and HfO₂. This asymmetry, together with results on a sample grown on a Si substrate, shows that incorporating oxygen impurity from the plasma itself is a minor part compared to diffusion from the SiO₂ substrate and HfO₂ dielectric during the PEALD growth. We observe the presence of TiO₂ at the interface between the Hf oxide layer and the Ti nitride electrodes as well as at the SiO₂ interface. EELS analysis led to a band gap ranging from 2.2 to 2.5 eV for the bottom TiN_xO_y and 1.7–2.2 eV for the top TiN_xO_y, which is in fair agreement with results obtained on the top TiN_x electrode (1.6 ± 01 eV) using optical absorption spectra. Measurement of sheet resistance, resistivity and temperature coefficient of resistance by a four-point probe on the top TiN_xO_y electrode from 20 to 100 °C corresponds to the typical values for semiconductors.

Ion beam etching of the anodic aluminium oxide barrier layer is demonstrated to be an effective and reproducible technique for preparing low-porosity templates for hyperbolic metamaterials with a certain spectral position of epsilon-near-zero point.

The results of RHEED, FTIR and Raman spectroscopy study of silicon and germanium films with the thickness up to 200 nm grown from molecular beams on dielectric Si$_3$N$_4$/SiO$_2$/Si(001) substrates are presented. Noticeable changes of the intensity of the N$-$H and Si$-$N absorption bands have been observed in the IR absorbance spectra as a result of the deposition of the silicon and germanium films. The thicker was the deposited film, the more considerable were the decrease of N$-$H absorption band intensity and the increase in that of the Si$-$N band. This tendency has been observed during the growth of both amorphous and polycrystalline Si or Ge films. The reduction of IR absorption at the band assigned to the N$-$H bond vibration is explained by breaking of these bonds followed by the diffusion of the hydrogen atoms from the Si$_3$N$_4$ layer into the growing film of silicon or germanium. The effect of the deposited film thickness on the diffusion of hydrogen is discussed within a model of the diffusion of hydrogen atoms controlled by the difference in chemical potentials of hydrogen atoms in the dielectric Si$_3$N$_4$ layer and the growing silicon or germanium film. Hydrogen atoms escape from the Si$_3$N$_4$ layer only during the deposition of a Si or Ge film when its thickness gradually grows. The interruption of the film growth stops the migration of hydrogen atoms into the film because of the decline in the chemical potential difference.