Enhancement of Sensitivity with High−Reflective−Index Guided−Wave Nanomaterials for a Long−Range Surface Plasmon Resonance Sensor

A guided−wave long−range surface plasmon resonance (GW−LRSPR) sensor was proposed in this investigation. In the proposed sensor, high−refractive−index (RI) dielectric films (i.e., CH3NH3PbBr3 perovskite, silicon) served as the guided−wave (GW) layer, which was combined with the long−range surface plasmon resonance (LRSPR) structure to form the GW−LRSPR sensing structure. The theoretical results based on the transfer matrix method (TMM) demonstrated that the LRSPR signal was enhanced by the additional high#x2212;RI GW layer, which was called the GW−LRSPR signal. The achieved GW−LRSPR signal had a strong ability to perceive the analyte. By optimizing the low− and high−RI dielectrics in the GW−LRSPR sensing structure, we obtained the highest sensitivity (S) of 1340.4 RIU−1 based on a CH3NH3PbBr3 GW layer, and the corresponding figure of merit (FOM) was 8.16 × 104 RIU−1 deg−1. Compared with the conventional LRSPR sensor (S = 688.9 RIU−1), the sensitivity of this new type of sensor was improved by nearly 94%.

Influence of radiation exposure on the properties of dielectric layers based on anodic aluminum oxide

Devices that are used in the aerospace industry must operate in extreme conditions, so it is important to understand how the properties of materials change under the influence of radiation and low temperatures. Anodic aluminum oxide, due to its mechanical and dielectric properties, is widely used in electronic devices with a high degree of integration. Radiation exposure can lead to degradation of the electrophysical parameters of dielectric films and can also change their chemical composition. The methods for studying the effect of radiation exposure on the dielectric properties of films are shown in this article. The research has been carried out and the results of the influence of α-particles on the dielectric properties of a porous film of anodic aluminum oxide during the influence of low temperature are presented.

High-k Fluoropolymers Dielectrics for Low-Bias Ambipolar Organic Light Emitting Transistors (OLETs)

Organic light emitting transistors (OLETs) combine, in the same device, the function of an electrical switch with the capability of generating light under appropriate bias conditions. In this work, we demonstrate how engineering the dielectric layer based on high-k polyvinylidene fluoride (PVDF)-based polymers can lead to a drastic reduction of device driving voltages and the improvement of its optoelectronic properties. We first investigated the morphology and the dielectric response of these polymer dielectrics in terms of polymer (P(VDF-TrFE) and P(VDF-TrFE-CFE)) and solvent content (cyclopentanone, methylethylketone). Implementing these high-k PVDF-based dielectrics enabled low-bias ambipolar organic light emitting transistors, with reduced threshold voltages (<20 V) and enhanced light output (compared to conventional polymer reference), along with an overall improvement of the device efficiency. Further, we preliminary transferred these fluorinated high-k dielectric films onto a plastic substrate to enable flexible light emitting transistors. These findings hold potential for broader exploitation of the OLET platform, where the device can now be driven by commercially available electronics, thus enabling flexible low-bias organic electronic devices.

FEATURES OF SELECTING DIELECTRIC LAYERS FOR ELECTROLUMINESCENT STRUCTURES

The paper considers an equivalent scheme of a thin-film electroluminescent emitter (TFELE), taking into account dielectric leaks, and proposes a criterion for the optimal choice of a dielectric in the structure to increase its efficiency. A calculation method is proposed for the optimal choice of material for dielectric films in an electroluminescent structure, taking into account their dielectric loss tangent. The algorithm for optimizing the parameters is based on the method of pairwise comparison of two dielectrics, provided that the charge flowing through the structure is constant or increased. The calculated data for materials are given in the form of a table according to the sequence of deterioration of their characteristics. The most attractive of the materials considered are PbTiO3, Ta2O5, Y2O3, as well as improved ceramics, which is confirmed by experiment. The possibility of applying the proposed model to explain the dependence of the luminosity of electroluminescent emitters on their excitation voltage is shown. A comparative analysis of the results of the calculation and experiment of the dependence of brightness on the applied voltage (B-V) for three types of TFELE based on a luminescent layer ZnS : Mn (0.5%) with a thickness of 0.6 μm, placed between two dielectric layers with a thickness of about 0.3- 0.35 μm with Ta2O5, Sm2O3 and Y2O3, respectively. It is established that the threshold luminescence excitation voltage correlates with the value of εE, and the maximum brightness with the value of εE / tg (δ). The table also shows the calculated characteristics of NdAlO3 and AlN films deposited by high-frequency magnetron sputtering. Higher brightness values can be expected from electroluminescent structures with such a dielectric than from structures with dielectric films with Sm2O3 and Y2O3. The results of such studies are presented in the form of a graph and table. This method can find practical application in the development of new materials and technologies for their production.

Electrical Characteristics and Reliability of SiCN/ Porous SiOCH Stacked Dielectric: Effects of Deposition Temperature of SiCN Film

Silicon carbonitride (SiCN) films deposited using silazane singe-precursor with different temperatures were capped onto porous carbon-doped silicon oxide (p-SiOCH) dielectric films. Effects on the electrical and reliability characteristics of the fabricated SiCN/p-SiOCH stacked dielectrics were investigated. Experimental results indicated that increasing the deposition temperature of the SiCN film increased barrier capacity against Cu migration under thermal and electrical stress and time-dependence-dielectric-breakdown reliability for the SiCN/p-SiOCH stacked dielectric. Therefore, this study provides a promising processing to deposit a SiCN barrier by elevating the deposition temperature and using N-methyl-aza-2,2,4-trimethylsilacyclopentane singe-precursor, which can be applied to back-end-of-line interconnects for advanced technological nodes in the semiconductor industry. A larger capacitance, however, is the main issue due to a larger intrinsic dielectric constant of the SiCN film and stronger plasma-induced damage on the p-SiOCH film. As a result, the related actions will be taken in the future research to improve this issue.

Evaluation of magnetic properties of thin magneto-dielectric films deposited from beam plasma in medium vacuum

By electron-beam evaporation of a solid state dielectrics (alumina ceramics) and a magnetic material (steel-3) in fore-vacuum, thin films of several μm, possessing both dielectric and magnetic properties, were deposited on a substrate. The work shows that the microstrip resonator method can be used to assess the presence of magnetic properties in films.