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Abstract Interface engineering is pivotal for enhancing the performance and stability of devices with layered structures, including solar cells, electronic devices, and electrochemical systems. Incorporating the interfacial dipole between the bulk layers effectively modulates the energy level difference at the interface and does not significantly influence adjacent layers overall. However, interfaces can drastically affect adjoining layers in ultrathin devices, which are essential for next‐generation electronics with high integrity, excellent performance, and low power consumption. In particular, the interfacial effect is pronounced in ultrathin semiconductors, which have a weak electric field screening effect. Herein, the substantial interfacial impact on the ultrathin silicon is shown, the p‐ to n‐type inversion of the semiconductor solely through the deposition of a self‐assembled monolayer (SAM) without external bias. The effects of SAMs with different interfacial dipoles are investigated by using Hall measurement and surface analytic techniques, such as UPS, XPS, and KPFM. Furthermore, the lateral electronic junction of the ultrathin silicon is engineered by the regioselective deposition of SAMs with opposite dipoles, and the device exhibits rectification behavior. When the interfacial dipole of SAM is manipulated, the rectification ratio changes sensitively, and thus the fabricated diode shows potential to be developed as a sensing platform.

Abstract Two-dimensional (2D) ferroelectric materials have emerged as significant platforms for multi-functional three-dimensional (3D) integrated electronic devices. Among 2D ferroelectric materials, ferro-ionic CuInP2S6 has the potential to achieve the versatile advances in neuromorphic computing systems due to its phase tunability and ferro-ionic characteristics. As CuInP2S6 exhibits a ferroelectric phase with insulating properties at room temperature, the external temperature and electrical field should be required to activate the ferro-ionic conduction. Nevertheless, such external conditions inevitably facilitate stochastic ionic conduction, which completely limits the practical applications of 2D ferro-ionic materials. Herein, free-standing 2D ferroelectric heterostructure is mechanically manipulated for nano-confined conductive filaments growth in free-standing 2D ferro-ionic memristor. The ultra-high mechanical bending is selectively facilitated at the free-standing area to spatially activate the ferro-ionic conduction, which allows the deterministic local positioning of Cu+ ion transport. According to the local flexoelectric engineering, 5.76×102-fold increased maximum current is observed within vertical shear strain 720 nN, which is theoretically supported by the 3D flexoelectric simulation. In conclusion, we envision that our universal free-standing platform can provide the extendable geometric solution for ultra-efficient self-powered system and reliable neuromorphic device.

Abstract Polycrystalline silicon (poly‐Si) is essential in integrated circuits and microelectromechanical systems. In addition, poly‐Si is gaining attention for next‐generation display research with high thermal conductivity, stability, and versatile applications. Conventional fabrication methods for doping patterns involve complex lithography and chemical usage, which have raised environmental concerns. The study of novel methods is necessary for environmental friendliness and a significant simplification of the manufacturing processes. This study introduces a novel bipolar work function control technology utilizing deionized water (DI‐W) and nanonewton‐scale mechanical force using an atomic force microscope. The method is implemented with a mechanically induced SiOx layer on poly‐Si in DI‐W. The induced Si─OH and Si─O bonds decreases the work function, whereas a thicker SiOx layer with a high oxidation state increases the work function. Based on the magnitude of the applied force (26.73–75.24 nN) and additional DI‐W immersion, the induced bond and thickness of the SiOx layer are controlled. Therefore, bipolar work function control is achieved in the range of −0.25–+0.103 eV. In addition, the electrical characteristics of the fabricated p‐ and n‐type poly‐Si diodes are investigated. This method is eco‐friendly and enables bipolar doping patterns in a single process with high efficiency.

In the era of big data, negative differential resistance (NDR) devices have attracted significant attention as a means of handling massive amounts of information. While 2D materials have been used to achieve NDR behavior, their intrinsic material characteristics have produced limited performance improvements. In this article, a facile phase modification method is presented via a plasma‐assisted sulfidation process to synthesize multiphased WS2 thin films, including distorted 1 T (D‐1 T) phase and 2 H phases for photoreactive NDR devices with p‐Si. The D‐1 T phase offers a feasible route to achieve high‐performance NDR devices with excellent stability and semimetallic properties. A comprehensive investigation of experimental and computational analyses elucidates the phase transition mechanism with various temperatures and electrical properties of D‐1 T WS2. In addition, optimizing electron tunneling in the multiple‐phased tungsten disulfide (MP‐WS2)/p‐Si heterojunction at MP‐WS2 with 77.4% D‐1 T phase results in superior NDR performance with a peak‐to‐valley current ratio of 13.8 and reliable photoreactive random‐access memory. This unique phase engineering process via plasma‐assisted sulfidation provides a pioneering perspective in functionalization and reliability for next‐generation nanoelectronics.

Abstract Molecular electronics enables functional electronic behavior via single molecules or molecular self‐assembled monolayers, providing versatile opportunities for hybrid molecular‐scale electronic devices. Although various molecular junction structures are constructed to investigate charge transfer dynamics, significant challenges remain in terms of interfacial charging effects and far‐field background signals, which dominantly block the optoelectrical observation of interfacial charge transfer dynamics. Here, tip‐induced optoelectrical engineering is presented that synergistically correlates photo‐induced force microscopy and Kelvin probe force microscopy to remotely control and probe the interfacial charge transfer dynamics with sub‐10 nm spatial resolution. Based on this approach, the optoelectrical origin of metal–molecule interfaces is clearly revealed by the nanoscale heterogeneity of the tip‐sample interaction and optoelectrical reactivity, which theoretically aligned with density functional theory calculations. For a practical device‐scale demonstration of tip‐induced optoelectrical engineering, interfacial tunneling is remotely controlled at a 4‐inch wafer‐scale metal–insulator–metal capacitor, facilitating a 5.211‐fold current amplification with the tip‐induced electrical field. In conclusion, tip‐induced optoelectrical engineering provides a novel strategy to comprehensively understand interfacial charge transfer dynamics and a non‐destructive tunneling control platform that enables real‐time and real‐space investigation of ultrathin hybrid molecular systems.

Abstract Band‐to‐band tunneling (BTBT) devices with superior subthreshold swing directly related to on/off switching speed and power consumption efficiency have emerged as a breakthrough of the limitation in conventional metal‐oxide‐semiconductor field‐effect transistors (MOSFETs). However, it is difficult to reach a higher level of electrical characteristics with only a combination of materials based on their intrinsic characteristics. External forces, such as electric fields, light, and temperature, can modulate the electron and hole concentration and control the tunneling probability and the electrical characteristics of heterostructure electronics. Recent articles employing external forces to improve the BTBT performance and demonstrate the mechanism of BTBT devices are summarized with five representative external forces. Moreover, the utility of the external force‐induced performance improvement of the BTBT device is also discussed by providing various applications.

Beyond conventional silicon, emerging semiconductor materials have been actively investigated for the development of integrated circuits (ICs). Considerable effort has been put into implementing complementary circuits using non-silicon emerging materials, such as organic semiconductors, carbon nanotubes, metal oxides, transition metal dichalcogenides, and perovskites. Whereas shortcomings of each candidate semiconductor limit the development of complementary ICs, an approach of hybrid materials is considered as a new solution to the complementary integration process. This article revisits recent advances in hybrid-material combination-based complementary circuits. This review summarizes the strong and weak points of the respective candidates, focusing on their complementary circuit integrations. We also discuss the opportunities and challenges presented by the prospect of hybrid integration.