Study of Gold Thin Films Evaporated on Polyethylene Naphthalate Films toward the Fabrication of Quantum Cross Devices

Abstract

We have studied Au thin films evaporated on polyethylene naphtalate (PEN) organic substrates as a function of Au thickness < ~20 nm and discussed its feasibility toward metal/insulator hybrid materials used for quantum cross devices using atomic force microscope. The Au grain size increases from 28.0±4.6 nm to 48.5±11.4 nm with increasing the Au thickness from 6.9 to 20.8 nm and it denotes that the Au grain size is larger than its Au-thickness size, respectively. The surface roughness of Au films of sub-15-nm thickness, in the scanning scale of the Au-thickness size, is less than 0.9 nm, corresponding to 4-5 atomic layers. These experimental results indicate that Au thin films on PEN substrates are suitable for possible metal/insulator hybrid materials to be used in quantum cross devices.

Fabrication of Nickel/Organic-Molecule/Nickel Nanoscale Junctions Utilizing Thin-Film Edges and Their Structural and Electrical Properties

“…9) The schematic illustration of the fabrication procedure has been reported in our previous papers. 9,10) Utilizing this DNB structure, we can expect to realize high-density memory devices, the crossing point of which can be scaled down to ultimate feature sizes of a few nanometers owing to their atomic-scale resolution of film thickness determined by the rate of metal deposition, ranging from 0.01 to 1 nm/s. One element of this structure is called a quantum cross (QC) device, which consists of two metal nanoribbons having the edge-to-edge configuration, as shown in Fig.…”

“…1. [9][10][11][12][13] In this QC device, the area of the crossed section is determined by film thickness, that is, 1-20 nm thick films could produce 1 Â 1-20 Â 20 nm 2 nanoscale junctions. This method offers a way to overcome the feature size limit of conventional optical lithography.…”