Designable lateral layered semiconductor multijunction overview: from controllable synthesis, property modulation to novel electronic devices.

Excitons are quasi-particles composed of electron–hole pairs through Coulomb interaction. Due to the atomic-thin thickness, they are tightly bound in monolayer transition metal dichalcogenides (TMDs) and dominate their optical properties. The capability to manipulate the excitonic behavior can significantly influence the photon emission or carrier transport performance of TMD-based devices. However, on-demand and region-selective manipulation of the excitonic states in a reversible manner remains challenging so far. Herein, harnessing the coordinated effect of femtosecond-laser-driven atomic defect generation, interfacial electron transfer, and surface molecular desorption/adsorption, we develop an all-optical approach to manipulate the charge states of excitons in monolayer molybdenum disulfide (MoS2). Through steering the laser beam, we demonstrate reconfigurable optical encoding of the excitonic charge states (between neutral and negative states) on a single MoS2 flake. Our technique can be extended to other TMDs materials, which will guide the design of all-optical and reconfigurable TMD-based optoelectronic and nanophotonic devices.

No abstract

As Moore's law deteriorates, the research and development of new materials system are necessary for moving towards the post Moore’s era. Traditional semiconductor materials, such as silicon, have been the cornerstone of modern technologies for more than half a century. This has been due to the abundant research and engineering on new techniques to continuously enrich silicon-based materials system and, subsequently, to develop better performed silicon based devices. Meanwhile, in emerging post Moore’s era, layered semiconductor materials, such as transition metal dichalcogenides, have piqued the interest of researchers due to their unique electronic and optoelectronic properties to power up the new era of next generation electronics. As a result, techniques to engineer the properties of layered semiconductors have expanded the possibilities of layered semiconductor-based devices. However, there are still few serious limitations on layered semiconductor synthesis and engineering, impeding the utilization of layered semiconductor-based devices for mass applications. As a practical alternative, heterogeneous integration between layered and traditional semiconductors provides valuable opportunities to combine the unique properties of layered semiconductors with well-developed traditional semiconductors materials system. Here, we provide an overview of the comparative coherence between layered and traditional semiconductors, starting with transition metal dichalcogenides as the representation of layered semiconductors. We highlight the meaningful opportunities presented by the heterogeneous integration of layered semiconductors with traditional semiconductors, which might be the optimum strategy for emerging semiconductor research community and chip industry in the next few decades.

No abstract