Covalent Molecular Assembly of Gold Nanoparticles for Non-Volatile Memory Applications

The synthesis of metal nanoparticles has been the focus of extensive research over the past decade due to their intriguing size and shape-dependent properties and, more importantly, their applications as building blocks for nanoelectronic devices. Controlled assembly of nanoparticles into ordered architectures on substrates is a promising path to develop miniaturized electronic and optical devices. The stability of nanostructures containing organic thin films has always been one of the critical issues in fabricating electronic devices. An avenue to solve this issue is to assemble nanoparticles covalently on to a desired surface to enhance stability of electronic devices for real-world applications.

In this work, we have synthesized thiol-functionalized gold nanoparticles (AuNPs) with a narrow size distribution (diameter °5 nm) as confirmed by Transmission electron microscopy (TEM). The Au NPs were immobilized on a SiO2 substrate using a functionalized polymer as a surface modifier. Microscopic and spectroscopic techniques were used to characterize the AuNPs and their morphology beofre and after immobilization. In addition, the electrical characterization of covalently bound Au NPs as a charge trapping layer in non-volatile memory is also investigated by means of a metal-insulator semiconductor (MIS) device. The present synthetic route to covalently immobilized gold nanoparticles system will be a step towards realization for the nanoparticle-based electronic devices and related applications.