Deconvolution of Tunneling Current in Large-Area Junctions Formed with Mixed Self-Assembled Monolayers

Abstract

Whereas single-component self-assembled monolayers (SAMs) have served widely as organic components in molecular and organic electronics, how the performance of the device is influenced by the heterogeneity of monolayers has been little understood. This paper describes charge transport by quantum tunneling across mixed SAMs of n-alkanethiolates of different lengths formed on ultraflat template-stripped gold substrate. Electrical characterization using liquid metal comprising eutectic gallium-indium alloy reveals that the surface topography of monolayer largely depends on the difference in length between the thiolates and is translated into distribution of tunneling current density. As the length difference is more significant, more phase segregation takes place, leading to an increase in the modality of Gaussian fitting curves. Consequently, statistical analysis permits access to deconvolution of tunneling currents, mirroring the phase-segregated surface. Our work provides an insight into the role of surface topography in the performance of molecular-scale electronic devices.

Mixed Molecular Electronics: Tunneling Behaviors and Applications of Mixed Self‐Assembled Monolayers

“…Katsouras et al8g examined the tunneling behaviors of large‐area junctions formed with mixed SAMs composed of n ‐alkanethiolates or n ‐alkanedithiolates of different lengths (C n X; n = number of carbons, X = end group, either monothiol (MT) or dithiols [DT]), and demonstrated the remarkable effect of molecular dilution on the on‐surface supramolecular structure of molecules, which significantly influenced the electrical characteristics of top contact and molecules in different microenvironments. They used the junctions of the form Au/SAM//PEDOT:PSS/Au, where PEDOT:PSS is poly(3,4‐ethylene‐dioxythiophene)‐poly(styrenesulfonate) as an interfacial layer to protect delicate monolayer surfaces against the gold top‐electrode deposition.…”

“…Although the field of molecular and organic electronics has long utilized pure molecular systems, studies on how charges traverse across multicomponent molecular systems have only recently emerged . This review article focuses on the emergence of, and recent advances in mixed molecular electronics, defined as an electronics field exploiting heterogeneous molecular systems such as mixed SAMs ( Figure ).…”

Binding Energy‐dependent Growth Behaviors and Surface Characteristics of Sequentially Polymerized Zincone Films

“…Many researchers have attempted to alter their electrical, optical, and mechanical properties to improve device performance. In these studies, the surface characteristics of the organic layers were important parameters for energy‐level alignment in electronic devices and were influenced by the fabrication process . Molecular layer deposition (MLD) is distinct from conventional solution‐based methods, as it is a vapor‐phase technique for the fabrication of organic and organic–inorganic hybrid thin films.…”

Single-cell RNA-seq data reveals TNBC tumor heterogeneity through characterizing subclone compositions and proportions

“…While these findings still focus on signature gene markers of cell subpopulations (Aarts et al, 2001;Arienti et al, 2017;Karaayvaz et al, 2018), but in our study we mainly analyze subclonal proportion in tissue bulks. Based on the deconvolution algorithm (Jin et al, 2018;Newman et al, 2015;Zeng et al, 2019), we connected single-cell level with bulk-tissue level by estimating subclones' proportion in tumor tissue then reveal genetic features, biological functions and clinical behaviors of TNBC subclones. And in result, we found that distinct subclone has its special function such as "regulation of T cell activation" in C1, "regulation of ARF GTPase activity" in C3, "programmed cell death" in C5 and so on.…”