Stochastically Broken Inversion Symmetry of Van der Waals Topological Insulator for Nanoscale Physically Unclonable Functions.

Owing to the exotic state of quantum matter, topological insulators have emerged as a significant platform for new-generation functional devices. Among these topological insulators, tetradymites have received significant attention because of their van der Waals (vdW) structures and inversion symmetries. Although this inversion symmetry completely blocks exotic quantum phenomena, it should be broken down to facilitate versatile topological functionalities.

Lateral Electronic Junction of a Single Ultrathin Silicon Induced by Interfacial Dipole of Self-Assembled Monolayer.

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.

Ultrastable 3D Heterogeneous Integration via N-Heterocyclic Carbene Self-Assembled Nanolayers.

The commercialization of 3D heterogeneous integration through hybrid bonding has accelerated, and accordingly, Cu-polymer bonding has gained significant attention as a means of overcoming the limitations of conventional Cu-SiO hybrid bonding, offering high compatibility with other fabrication processes. Polymers offer robust bonding strength and a low dielectric constant, enabling high-speed signal transmission with high reliability, but suffer from low thermomechanical stability. Thermomechanical stability of polymers was not achieved previously because of thermal degradation and unstable anchoring.

Remote-Controllable Interfacial Electron Tunneling at Heterogeneous Molecular Junctions via Tip-Induced Optoelectrical Engineering.

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.

Hybrid Thin-Film Materials Combinations for Complementary Integration Circuit Implementation.

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.

Energy-Band Engineering by Remote Doping of Self-Assembled Monolayers Leads to High-Performance IGZO/p-Si Heterostructure Photodetectors.

Metal oxide semiconductors are of great interest for enabling advanced photodetectors. However, operational instability and the absence of an appropriate doping technique hinder practical development and commercialization. Here, a strategy is proposed to dramatically increase the conventional photodetection performance, having superior stability in operational and environmental atmospheres.

Unprecedentedly Uniform, Reliable, and Centimeter-Scale Molybdenum Disulfide Negative Differential Resistance Photodetectors.

Negative differential resistance (NDR) can be applied to various devices such as reflection amplifiers, relaxation oscillators, and neuromorphic devices. However, the development of NDR photodetectors with uniformity, stability, and reproducibility for use in practical applications is still lacking. Herein, we demonstrate highly reliable NDR photodetectors by constructing a MoS/-Si heterostructure.

Recyclable free-polymer transfer of nano-grain MoS film onto arbitrary substrates.

Clean transfer of transition metal dichalcogenides (TMDs) film is highly desirable, as intrinsic properties of TMDs may be degraded in a conventional wet transfer process using a polymer-based resist and toxic chemical solvent. Residues from the resists often remain on the transferred TMDs, thereby causing a significant variation in their electrical and optical characteristics. Therefore, an alternative to the conventional wet transfer method is needed-one in which no residue is left behind.