Analysis of the charging kinetics in silver nanoparticles-silica nanocomposite dielectrics at different temperatures

C Djaou,L Boudou,C Villeneuve-Faure,K Makasheva,G Teyssedre

doi:10.1088/2632-959x/ac3886

Abstract

Dielectric nanocomposite materials are now involved in a large panel of electrical engineering applications ranging from micro-/nano-electronics to power devices. The performances of all these systems are critically dependent on the evolution of the electrical properties of the dielectric parts, especially under temperature increase. In this study we investigate the impact of a single plane of silver nanoparticles (AgNPs), embedded near the surface of a thin silica (SiO2) layer, on the electric field distribution, the charge injection and the charge dynamic processes for different AgNPs-based nanocomposites and various temperatures in the range 25°C–110°C. The electrical charges are injected locally by using an Atomic Force Microscopy (AFM) tip and the related surface potential profile is probed by Kelvin Probe Force Microscopy (KPFM). To get deeper in the understanding of the physical phenomena, the electric field distribution in the AgNPs-based nanocomposites is computed by using a Finite Element Modeling (FEM). The results show a strong electrostatic coupling between the AFM tip and the AgNPs, as well as between the AgNPs when the AgNPs-plane is embedded in the vicinity of the SiO2-layer surface. At low temperature (25°C) the presence of an AgNPs-plane close to the surface, i.e., at a distance of 7 nm, limits the amount of injected charges. Besides, the AgNPs retain the injected charges and prevent from charge lateral spreading after injection. When the temperature is relatively high (110°C) the amount of injected charges is increased in the nanocomposites compared to low temperatures. Moreover, the speed of lateral charge spreading is increased for the AgNPs-based nanocomposites. All these findings imply that the lateral charge transport in the nanocomposite structures is favored by the closely situated AgNPs because of the strong electrostatic coupling between them, additionally activated by the temperature increase.

Highlights

Any of the future directions of development of micro-/nano-electronics, beyond-Complementary Metal Oxide Semiconductor (CMOS) systems or sensors, requires scaling down the size of developed devices, reducing their energy consumption and refining their performances under enlarged environmental constraints As clearly indicated in a recent roadmap for European Nanoelectronics a major challenge would be to solve issues related to energy losses and heating, with the latter potentially leading to a strong evolution of the electrical characteristics of the device [1]
In this study we addressed the impact of a single plane of AgNPs embedded in a SiO2 layer close to its surface on the electric field distribution, the charge injection and the charge dynamic processes for different AgNPs-based NCs and various temperatures in the range 25°C–110°C
Electrostatic modelling by Finite Element Model (FEM) of these heterogeneous structures and measurements by Kelvin Probe Force Microscopy (KPFM) of the surface potential after charge injection are combined to reveal the impact of the AgNPs on the electric field distribution and on the processes of charge injection

Summary

Introduction

Any of the future directions of development of micro-/nano-electronics, beyond-Complementary Metal Oxide Semiconductor (CMOS) systems or sensors, requires scaling down the size of developed devices, reducing their energy consumption and refining their performances under enlarged environmental constraints (temperature variations, humidity, exposure to intense light, etc.) As clearly indicated in a recent roadmap for European Nanoelectronics a major challenge would be to solve issues related to energy losses and heating, with the latter potentially leading to a strong evolution of the electrical characteristics of the device [1] To overcome these problems rational engineering and characterization of new materials, like core–shell nanomaterials [2, 3], 2Dmaterials (for example MoS2) [4], alternative channel materials for CMOS, high-k dielectrics [5, 6], multi-gates, thin layers, heterostructures, etc., are timely due. Tuning of the electrical properties in a very broad range can be achieved by controlling the size, density, and distribution of metal nanoparticles:

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Results

Conclusion