A critical requirement for the application of organic thin-film transistors (TFTs) in mobile or wearable applications is low-voltage operation, which can be achieved by employing ultrathin, high-capacitance gate dielectrics. One option is a hybrid dielectric composed of a thin film of aluminum oxide and a molecular self-assembled monolayer in which the aluminum oxide is formed by exposure of the surface of the aluminum gate electrode to a radio-frequency-generated oxygen plasma. This work investigates how the properties of such dielectrics are affected by the plasma power and the duration of the plasma exposure. For various combinations of plasma power and duration, the thickness and the capacitance of the dielectrics, the leakage-current density through the dielectrics, and the current–voltage characteristics of organic TFTs in which these dielectrics serve as the gate insulator have been evaluated. The influence of the plasma parameters on the surface properties of the dielectrics, the thin-film morphology of the vacuum-deposited organic-semiconductor films, and the resulting TFT characteristics has also been investigated.

4H–silicon carbide (SiC) shows the capability of hosting a large number of promising emitters for quantum technology. However, due to its high refractive index, the collection of photoluminescence emission is compromised for further applications. Here, we demonstrate a scalable approach of manufacturing solid-immersion lenses (SILs) on 4H–SiC. The procedure results in SILs with high effective NA. The fluorescence collection efficiency of single quantum emitters under the SILs shows 3.4 times enhancement confirmed by confocal microscopy of individual V2.

We studied chemical stability of atomic layer deposition-grown Al2O3 artificial solid electrolyte interphases (SEIs) on lithium and sodium upon contact with liquid electrolyte by electrochemical impedance spectroscopy (EIS) and in the case of Li also by x-ray photoelectron spectroscopy. Both methods show that the formed Al2O3 is porous for all nominal thicknesses, and that the natural SEI grows in its pores and cracks. EIS shows that the porosity of the SEI on Na is higher than the one observed on Li, in particular at higher nominal thicknesses of Al2O3. The observed values of activation energies related to the transport through the SEI indicate either a denser natural SEI in the pores of Al2O3 and/or considerable space charge effect between Al2O3 and the SEI phase.

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