Improved figures of merit of nano-Schottky diode by embedding and characterizing individual gold nanoparticles on n-Si substrates

Abstract

Improving Schottky diode characteristics in semiconducting devices is essential for better functionality in electronic and optoelectronic devices at nanoscale. In this paper, we investigate the electric transport characteristics of a gold (Au)-tip/n-Si-based nano-Schottky diode by using a conductive-mode atomic force microscope (CAFM). First, 10 nm average diameter Au nanoparticles (NPs) are monodispersed on the highly cleaned n-type Si substrate using an optimized spin-coating technique. The controlled and well dispersed NPs are confirmed by using the AC imaging mode of the AFM. The electrical characteristics are established by using an Aucoated AFM tip, by either soft engaging at the surface of the n-Si substrate or at the top of an individual Au NP. Landing of the AFM tip on the NP or n-Si substrate is validated by the force curves of the AFM. From the localized CAFM electrical characteristics, we observed the improvement in the figures of merit (FOM) that characterize the rectification performance including the (1-V) asymmetry ( f ASYM ), and the turn-on voltage due to placing the Au NP between the AFM tip and n-Si substrate. These improved FOM of the nanoscale diodes are explained based on the increase in the tunneling current at the nanoscale Au-NP/n-Si interface. Moreover, the nanoscale control of interface structure is extremely important to improve the characteristics of nano-Schottky diodes.

Nanojunction Material Effect on the Photoelectric Response of Single-Wall Carbon Nanotube Rectennas

“… 1 One of the novel techniques to realize nanoantennas at a nanoscale is to utilize nanoprobes (or ultrasharp tips) 2 − 4 that will be used to make physical contact with individual CNTs and form a nano-Schottky diode rectifier. 5 Additionally, we have demonstrated the feasibility of designing an optical rectenna by engineering a rectifying diode at the interface between a metal nanoprobe of an atomic force microscope (AFM) and single-wall carbon nanotubes (SWCNTs). 6 This has paved the way for more investigations, wherein, in this work, we study the effect of the metal type of the nanoprobe on the rectenna performance.…”

Single wall carbon nanotube based optical rectenna

“…Moreover, this has been integrated with a new approach used for modeling and fabrication of a tunneling-based nano-Schottky diode rectier. 5 CNTs' outstanding electrical, mechanical, and physical properties make them ideal candidates for many potential applications including transistors, [6][7][8] gas sensors, 9,10 optical sensors, 11 light emitters 12,13 and for MEMS/NEMS applications. 14 Also, CNTs make exemplary antenna elements as they absorb electromagnetic energy in a broad spectrum.…”

Time dependence of electrical characteristics during the charge decay from a single gold nanoparticle on silicon

“…[5][6][7][8][9] Namely, it has been reported that the photodetection and electrical characteristics depend only on the size of the metal-semiconductor nano interfaces. [10][11][12] Because of their compatibility with organic compounds and ability to bond with reduced graphene oxide the Au-NPs have been used to improve the efficiency of semiconducting devices. 13,14 The Au-NPs, being chemically stable with high work function, are considered to be excellent candidates for charge trapping elements.…”

“…The distribution of these NPs on the substrate can be controlled by different deposition methods like spin coating and dip coating. 11,26,27 Recently, the solution processed Au-NPs have been used for electron storage centers by properly embedding NPs in the carefully engineered blocking and tunneling layers of Al 2 O 3 on an n-Si substrate. 26 To characterize individually or discretely dispersed NPs on the substrate, atomic force and scanning tunneling microscopies (AFM and STM) are considered to be among the best tools.…”

“…[28][29][30] Earlier, we have shown the signicant effect of individual NPs deposited on a thin lm passivated n-Si substrate on the enhancement of the electric eld, and, in turn, on the reverse tunneling current through the nano-Schottky junction. 11 In this work, the effect of the charge trapped in the NP on the I-V characteristics of the nano Schottky junctions, formed between the NP and Si substrate, and the time evolution of the I-V curves during the charge decay is studied. Moreover, this will help to assess and optimize the use of these metal nanoparticles in future memory based devices.…”