Research Institute of Industrial Science and Technology

Tellurium (Te) is increasingly gaining attention as a scalable p-type channel material owing to its inherently high carrier mobility and ambient stability. However, in sub-5 nm Te channels, high contact resistance remains a major obstacle to achieving high-performance device operation. In this study, an estimated contact resistance of ≈1.7 kΩ·μm is obtained in 4 nm-thick Te channels by engineering the band structure in the source and drain (S/D) regions using a raised source and drain (RSD) structure. To isolate intrinsic contact behavior, electrical measurements are conducted at 77 K, in which thermally activated defect states are suppressed, and carrier injection is dominated by the metal-semiconductor interface. Transport characterization reveals a more than 17-fold increase in on-state current and a more than 50-fold reduction in contact resistance relative to Te devices without the RSD structure. This enhancement is attributed to selectively increasing the Te thickness at the S/D terminals, which tunes the bandgap by thickness-dependent modulation. The resulting RSD architecture enhances tunneling current by narrowing the barrier width─modulated by gate bias. This scalable, low-temperature approach offers broad applicability to other ultrathin channel materials.

ABSTRACT Developing high‐energy lithium batteries inevitably involves separators that suppress uncontrolled ion transport and parasitic reactions over repeated cycling. Here, we introduce a dual‐functional active separator comprising a uniformly dip‐coated double‐bond‐containing poly(vinylidene fluoride) (DPVDF) layer with covalently cross‐linked branched polyethyleneimine (BPEI) robust framework interfaces. The amine‐enriched DPVDF–BPEI‐modified separator (PDB) electrostatically regulates PF 6 − anions, as evidenced by spectroscopic, computational, and electrochemical studies. PF 6 − regulation suppresses significantly hydrofluoric acid (HF)‐forming fragmentation and facilitates selective Li + diffusion, leading to ca. twice higher Li + transference numbers (polypropylene (PP): 0.49 and PDB: 0.80) and ca. 3 times higher Li + diffusion coefficient (PP: 0.46 × 10 −6 and PDB: 1.29 × 10 −6 cm 2 s −1 ) than PP. In addition, it thereby results in the formation of ultrathin, compositionally uniform electrode–electrolyte interphases (SEI/CEI). Those unique effects of the PDB enable long‐term stability, ca. 1,000 cycles in Li||LFP and ca. 400 cycles in Li||NCM811 half‐cells. The Si||LFP full‐cell exhibits stable cycling for more than 400 cycles at 3.0 C. The PDB supports dendrite‐free operation for 1,000 h in Li||Li symmetric cells, demonstrating uniform Li deposition. This work establishes a scalable separator design strategy that integrates structural durability with targeted anion regulation and efficient ion‐diffusion control, providing a practical pathway toward stable, high‐energy lithium‐based batteries.

ABSTRACT Co‐integration of extremely thin n‐ and p‐type semiconductor layers deposited in wafer‐scale at low temperatures (≤200°C) opens new avenues for novel electronic devices. Here, a multi‐functional ZnO–Te heterojunction device exhibiting double negative differential transconductance (D‐NDT) characteristics is presented. By modulating the overlap length of n‐ and p‐type regions, the carrier transport mechanism transitions from single NDT to D‐NDT, enabling multi‐state switching within a single device. Leveraging the unique double‐peak transfer curve, a single‐stage frequency quadrupler is demonstrated, resulting in a reduction of device count by 64%–75% compared to standard analog and digital circuit topologies. The functionality of the frequency quadrupler is verified using a system clock generator driving a 2‐bit binary counter, achieving a fourfold increase in data processing throughput within a single input cycle. These results suggest that the ZnO–Te D‐NDT device offers a promising pathway for realizing area‐efficient and multi‐functional integrated circuits for future electronics.

Stacked Graphene Films The diagram illustrates the use of a pellicle made from a multilayer composite film, composed of layer-by-layer stacked graphene, for extreme ultraviolet (EUV) lithography. This graphene-based pellicle offers excellent optical transparency, mechanical strength, and thermal stability, ensuring superior protection for the photomask during EUV exposure and minimizing degradation or contamination. More information can be found in the Research Article by Yun Sung Woo, Byung Hee Hong, and co-workers (10.1002/adfm.202518685).

Abstract Graphene is a promising material for next‐generation extreme ultraviolet (EUV) pellicles due to its excellent optical transparency, mechanical, and thermal stability under intense EUV radiation. However, challenges remain in precisely controlling its thickness at large scales and preventing hydrogen radical‐induced degradation. In this study, a multilayer graphene composite with protective capping layers, enabling nanometer‐scale thickness control is devloped. A 10‐layer, 5 nm thick graphene film achieves ≈92% transparency and an effective Young's modulus of 220 GPa. When integrated into a free‐standing molybdenum (Mo)/graphene/silicon nitride (SiN) composite, the Young's modulus increases by 29%, and the fracture load improves by 840% compared to a single‐layer SiN membrane. Molecular dynamics simulations confirm that the enhanced mechanical strength mainly results from graphene's intrinsic properties. Additionally, a full‐size pellicle with five graphene layers and a 100 nm SiN layer are fabricated, which maintains over 90% EUV transparency on a 7 nm SiN substrate. These results suggest that multilayer graphene membranes can overcome current EUV pellicle limitations and support the broader commercialization of EUV lithography in the near future.