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Ferroelectric hafnia is one of the most promising materials for next generation of non-volatile memory devices. Several strategies have demonstrated to be of interest to improve its functional properties. Interface engineering, realized by the introduction of additional layer in the capacitor structure, is demonstrated as a promising strategy. However, interface layers can have multiple implications, such as changes in the chemistry of the interfaces and an increase of depolarization field, whose effects are difficult to discriminate. The role of HfO2 and ZrO2 capping is explored on polarization, retention, endurance, and leakage properties of Hf0.5Zr0.5O2 epitaxial films. In HfO2 capped films, lower polarization is observed, and endurance and retention are also comparably worse than in ZrO2 capped films. Complementary under illumination ferroelectric characterization and capacitance measurements indicate a reduction of defects and interface capacitance contribution in ZrO2 capped films. For both cappings, the interfaces with the Hf0.5Zr0.5O2 layer are shown to be compositionally sharp and the phase of Hf0.5Zr0.5O2 (HZO) grains is replicated on the capping layer, indicating that electrostatic effects prevail and that the use of interface layers with high permittivity, here ZrO2, is crucial to favor good functional properties.

Silicon core optical fibres have been fabricated using an experimental draw tower based on a CO laser furnace. Fabricated fibres have achieved a submicron core size and shown a record low loss of 0.1 dBcm. Frontiers in Optics / Laser Science, Part of proceedings: ISBN 978-1-55752-820-9 QC 20220927

The effects of Pd, Ni, Nb, and Ti interface layers on the thermal stability of Ag films were investigated, and those metals that are appropriate for the interface layers were summarized. The results indicated that Ti and Nb interface layers resulted in thermally stable Ag films by improving the adhesion strength of the Ag films to SiO2 substrates and by enhancing the crystal orientation of Ag(111). It was determined that appropriate interface layer metals for Ag film should have a large Gibbs free energy of formation for the oxide and an appropriate atomic diameter ratio of dmetal/dAg.

This paper presents an assessment of titanium tungsten (TiW) coatings and their applicability as components of biosensing systems. The focus is put on using TiW as an electromechanical interface layer between carbon nanotube (CNT) forests and silicon nanograss (SiNG) cell scaffolds. Cytotoxicity, applicability to plasma-enhanced chemical vapor deposition (PECVD) of aligned CNT forests, and electrochemical performance are investigated. Experiments include culturing of NIH3T3 mouse embryonic fibroblast cells on TiW coated silicon scaffolds, CNT growth on TiW substrates with nickel catalyst, and cyclic voltammetric investigation with PBS-buffered potassium hexacyanoferrate (II/III).

The increasing usage of lithium titanate (Li4Ti5O12; LTO) as anode material in Li-ion batteries creates challenges and possibilities for the electrolytes. Traditional Li-ion battery electrolytes are tailored primarily for chemistries that use graphite as anode, and are therefore not optimized for LTO electrodes. In this study, propylene carbonate is, together with LiPF6 salt, investigated as an alternative electrolyte system in such batteries. The LTO surface is investigated with photoelectron spectroscopy after the formation cycle and after 10 cycles to characterize the decomposition products. The results show the presence of a surface layer formed on the LTO electrode irrespective of counter electrode used, but with varying thickness. Contrary to conventional ethylene carbonate based electrolytes, no manganese crossover could be observed when using either lithium manganese oxide or lithium nickel manganese oxide/lithium cobalt oxide composite as cathodes in LTO cells.