{"title":"Ultralow Electron Temperature Plasma for Damage-Reduced Processing of High-k/Metal Gate Films toward Vertically Stacked Nanosheet Devices","authors":"Hyung-dong Kim,Hyeonho Nahm,Seokhyeon Ha,Youngdon Kim,Min-seok Kim,Chin-Wook Chung","doi":"10.1021/acs.nanolett.6c02458","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c02458","url":null,"abstract":"In vertically stacked nanosheet devices, repeated plasma-processing steps are required to realize multiple threshold voltages (Vth), but such repeated exposure can accumulate plasma-induced damage (PID) in ultrathin high-k/metal gate (HKMG) stacks. Here, we demonstrate that ultralow electron temperature (ULET, Te < 1 eV) plasma generated using a DC-biased grid suppresses PID by controlling the electron temperature and ion energy distribution function (IEDF). Compared with conventional inductively coupled plasma processing at the same substrate bias (−100 V), ULET plasma reduces the mean ion energy from 131 to 101 eV and reduces the IEDF standard deviation by 44% (from 37.4 to 20.9 eV). Consequently, surface roughness decreases by up to 58%, fluorine incorporation decreases by up to 58%, and HfO2 Raman-band intensities are 1.32–1.81 times those under conventional ICP processing. These results establish electron-temperature control as a key parameter for minimizing PID in HKMG films relevant to vertically stacked nanosheet devices.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"11 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano LettersPub Date : 2026-11-10DOI: 10.1021/acs.nanolett.6c03898
Alba Arroyo-Fructuoso,Gianluca Balestra,Marco Esposito,René Hübner,Gregor Hlawacek,Rosa Córdoba
{"title":"Tungsten–Carbon Nanohelix Arrays by Helium-Ion Direct Writing: Geometry-Dependent Circular-Polarization Response in the Visible","authors":"Alba Arroyo-Fructuoso,Gianluca Balestra,Marco Esposito,René Hübner,Gregor Hlawacek,Rosa Córdoba","doi":"10.1021/acs.nanolett.6c03898","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c03898","url":null,"abstract":"3D nanohelices provide a direct route to control light–matter interactions with circular polarization at the nanoscale. Here, we report periodic arrays of W–C nanohelices fabricated by He+ focused-ion-beam-induced deposition (FIBID), combining direct-write 3D growth with high spatial resolution and W-rich deposits (∼65 at. % W). Two arrays with the same lateral geometry were fabricated while varying only the vertical pitch, corresponding to helical ratios HR ≈ 1 and HR ≈ 2. Transmittance measurements under circularly polarized light reveal a clear geometry-dependent response. The compact nanohelices (HR ≈ 1) show a larger circular-polarization-dependent transmission contrast (g ≈ 0.17, θ ≈ 2.35°), moderate transmittance (∼30–50%), and a sign inversion near 600 nm. The larger-pitch helices (HR ≈ 2) show higher transmittance (∼35–100%) with a weaker but stable response (g ≈ 0.13, θ ≈ 1.60°). Qualitative simulations reproduce the main spectral trends and support distinct optical responses of the two pitch geometries.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"14 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano LettersPub Date : 2026-11-10DOI: 10.1021/acs.nanolett.6c04636
Mohammad Bagheri,Pekka Koskinen
{"title":"Machine-Learning-Accelerated Metallene Stabilization from High-Throughput Sandwich Modeling","authors":"Mohammad Bagheri,Pekka Koskinen","doi":"10.1021/acs.nanolett.6c04636","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c04636","url":null,"abstract":"Metallenes have appealing properties, but stabilizing them in a monolayer phase poses synthesis challenges. A recent experiment showed that the van der Waals squeezing method can stabilize certain metallenes in a MoS2 sandwich. This pioneering work motivates systematic studies, but such studies are experimentally impractical, while first-principles modeling remains prohibitive. Here, using universal machine-learning interatomic potentials, we constructed 1620 metallene sandwich heterostructures containing 6 different sandwich layers and 45 metals. We performed phonon calculations, which revealed 1208 dynamically stable structures and narrowed them to 331 after structural filtering. We found that Se-based transition-metal dichalcogenides stabilize metallenes effectively. Specifically, hexagonal and buckled hexagonal crystal lattices exhibit the greatest stability. We further evaluated the thermal stability of selected heterostructures with density-functional-theory molecular dynamics simulations at room temperature. By uncovering the physical and chemical factors that govern metallenes stabilization, our results provide systematic insights to guide and accelerate synthesis for future applications.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"23 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Intrinsically Moiré-Patterned Two-Dimensional Polymorphic Networks for Modulated Charge Order and Proximity Superconductivity","authors":"Yanhao Shi,Hui Chen,Qian Fang,Jingyi Duan,Zhongyi Cao,Yikai Chen,Haitao Yang,Wei Jiang,Hui Guo,Hong-Jun Gao","doi":"10.1021/acs.nanolett.6c03918","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c03918","url":null,"abstract":"Moiré superlattices provide a versatile route to engineering correlated electronic and topological states in van der Waals heterostructures, yet their use to organize structural polymorphism and phase-selective charge, magnetic, and superconducting states within a single two-dimensional material remains elusive. Here, we report modulated charge order and proximity superconductivity in an intrinsically moiré-patterned 1T/1T′ polymorphic network of monolayer VTe2 grown epitaxially on superconducting NbSe2. Scanning tunneling microscopy/spectroscopy and first-principles calculations show that in situ annealing of twist-moiré VTe2/NbSe2 creates alternating 1T and 1T′ domains. The origin of the selective 1T-to-1T′ conversion is due to the moiré-induced anisotropic strain. This moiré-registered network hosts phase-specific short-range charge orders: 4 × 4 in 1T and 3 × 3 in 1T′. In the proximity-superconducting regime, spatially modulated in-gap bound states and suppressed coherence peaks reveal phase-dependent magnetic pair breaking. This work establishes intrinsically moiré-patterned polymorphism as a route to programmable two-dimensional quantum materials.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"24 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano LettersPub Date : 2026-11-10DOI: 10.1021/acs.nanolett.6c02894
Juho Luomahaara,Kristupas Razas,Omid Sharifi Sedeh,Renan P. Loreto,Janne S. Lehtinen,Mingchi Xu,Armel A. Cotten,Aldo Tarascio,Peter Müller,Nikolai Yurttagül,Lassi Lehtisyrjä,Leif Grönberg,Christian P. Scheller,Jonathan R. Prance,Michael D. Thompson,Richard P. Haley,Mika Prunnila,Dominik M. Zumbühl
{"title":"A Scalable Nonsuperconducting Tunnel Junction Technology","authors":"Juho Luomahaara,Kristupas Razas,Omid Sharifi Sedeh,Renan P. Loreto,Janne S. Lehtinen,Mingchi Xu,Armel A. Cotten,Aldo Tarascio,Peter Müller,Nikolai Yurttagül,Lassi Lehtisyrjä,Leif Grönberg,Christian P. Scheller,Jonathan R. Prance,Michael D. Thompson,Richard P. Haley,Mika Prunnila,Dominik M. Zumbühl","doi":"10.1021/acs.nanolett.6c02894","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c02894","url":null,"abstract":"Tunnel junctions are essential for various technologies ranging from classical microelectronics to quantum information and cryogenic electronics. Aluminum and its oxide (AlOx) have long dominated cryogenic and quantum tunnel junction applications for their excellent material quality and superconductivity. However, some applications require junctions to remain normal conducting, either as standalone components or integrated with superconducting circuitry. Magnetic fields, impurity doping, or proximity effects can suppress superconductivity, but often pose challenges for scalability and integration. Here, we present a CMOS-compatible normal conducting tunnel junction platform using TiW alloy electrodes and AlOx tunnel barriers, achieving high yield and uniformity through wafer-scale fabrication. As a cryogenic use-case, the wafers incorporate junction arrays designed for Coulomb blockade thermometry, confirming reliable normal conducting state performance down to 20 mK. These results demonstrate a scalable and integrable normal conducting junction technology, supporting its use in cryogenic, quantum, and nanoelectronic systems, including hybrid superconducting-normal metal circuits.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"44 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano LettersPub Date : 2026-11-10DOI: 10.1021/acs.nanolett.6c04118
Honey Boban,Tanguy Prongué,Amarjyoti Choudhury,Dario Marchiani,Salony Mandloi,Andrés Bareño,Felix Eder,Enrico Giannini,Fabian O. von Rohr,Alberto F. Morpurgo,Marco Gibertini,Anna Tamai,Felix Baumberger
{"title":"Quasi-One-Dimensional Topological Band Structure and Van Hove Singularities in Monolayer TaIrTe4 from Laser μ-ARPES","authors":"Honey Boban,Tanguy Prongué,Amarjyoti Choudhury,Dario Marchiani,Salony Mandloi,Andrés Bareño,Felix Eder,Enrico Giannini,Fabian O. von Rohr,Alberto F. Morpurgo,Marco Gibertini,Anna Tamai,Felix Baumberger","doi":"10.1021/acs.nanolett.6c04118","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c04118","url":null,"abstract":"Recent transport experiments reported a quantum spin Hall insulator phase in monolayer 1T-TaIrTe4 gated away from charge neutrality. This phase is not predicted by band structure calculations and has been attributed to an electronic instability induced by strong correlations at a putative Van Hove singularity. Here, we investigate the electronic structure of exfoliated monolayer 1T-TaIrTe4 using microfocus laser angle resolved photoemission. We find a strongly anisotropic band structure susceptible to density wave instabilities. Our data further reveal a saddle point singularity in the density of states. However, we find that the saddle point lies at a density for which linear transport experiments found no anomalies. Moreover, the quasiparticle line widths suggest weak electron correlations only. This points to a secondary role of Van Hove singularities and electron correlations in the transport phase diagram of monolayer 1T-TaIrTe4.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"1 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano LettersPub Date : 2026-11-10DOI: 10.1021/acs.nanolett.6c03563
Bruno Stojcic,Ana Agostinho,Luca Panconi,Hans Blom,Hjalmar Brismar
{"title":"Direct Visualization of Na,K-ATPase Clustering by 3D DNA-PAINT MINFLUX Nanoscopy","authors":"Bruno Stojcic,Ana Agostinho,Luca Panconi,Hans Blom,Hjalmar Brismar","doi":"10.1021/acs.nanolett.6c03563","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c03563","url":null,"abstract":"The sodium–potassium pump (Na,K-ATPase) is an essential plasma-membrane transporter that consumes 20%–30% of cellular energy, and up to approximately 50% in the kidneys. Whether it assembles into defined oligomers in its native membrane has been debated for decades. Resolving this question demands imaging precision at molecular length scales. Here, we combine 3D MINFLUX nanoscopy with DNA-PAINT to map EGFP-tagged Na,K-ATPase α1 and β1 subunits in mammalian cells with 3–5 nm localization precision. We introduce two point-cloud analysis tools: a data-driven algorithm that assigns localizations to the apical or basal membrane, removing trans-membrane artifacts, and a sequential nearest-neighbor analysis that estimates oligomer stoichiometry without structural priors. Both subunits show preferential nearest-neighbor distances of approximately 7 nm, direct evidence of dimerization, and are further organized into nanoclusters of approximately 7 to 12 molecules. These results provide direct structural evidence of Na,K-ATPase self-assembly and a framework for quantifying membrane-protein clustering at single-molecule resolution.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"6 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Single-Twinned Seed-Mediated Synthesis of Au Right Bipyramids for Uniform Near-Field Focusing","authors":"Hao Zhang,Chenyang Luo,Yu Lan,Bin Dong,Xiang Lin,Shunping Zhang,Hongxing Xu","doi":"10.1021/acs.nanolett.6c03991","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c03991","url":null,"abstract":"Noble metal nanoparticles with sharp edges and corners, such as triangles, tetrahedrons, bipyramids, etc., support superior plasmonic field enhancement for enhanced spectroscopy. However, high-yield synthesis of gold right bipyramids (Au RBPs) with sharp tips has remained limited because they have a single-twinned (ST) crystal structure whose growth pathway is hard to control. Here, we report the seed-mediated growth of Au RBPs using ST seeds, achieving a yield exceeding 70% by moderately increasing the size of these seeds. Au RBPs with sizes from 34 to 94 nm and controlled corner sharpness are achieved through the regulation of seed and bromide amounts. Uniform and strong near-field enhancement is generated in the Au RBPs-on-mirror configuration, which outperforms the well-established nanocube-on-mirror configuration in Raman enhancement. This work highlights the merits of ST seed-mediated growth for anisotropic nanocrystals and their potentials in plasmonic near-field focusing.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"15 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano LettersPub Date : 2026-11-10DOI: 10.1021/acs.nanolett.6c03121
Rebecca Rahmel,Hristiyana Kyoseva,Lukas Conrads,Matthias Wuttig,Gero von Plessen,Thomas Taubner
{"title":"Optical Resonance Tuning of Single Polystyrene Microspheres Using the Phase-Change Material In3SbTe2 as a Switchable Mirror","authors":"Rebecca Rahmel,Hristiyana Kyoseva,Lukas Conrads,Matthias Wuttig,Gero von Plessen,Thomas Taubner","doi":"10.1021/acs.nanolett.6c03121","DOIUrl":"https://doi.org/10.1021/acs.nanolett.6c03121","url":null,"abstract":"Dielectric nanoparticles and microparticles show rich optical responses due to their electric and magnetic multipolar Mie modes and low losses. These optical resonances can be modified via the particle size, shape, and dielectric environment. Here we tune the infrared multipolar Mie resonances of dielectric polystyrene microspheres using the plasmonic phase-change material In3SbTe2 (IST). IST exhibits a phase change between a dielectric amorphous phase and a crystalline phase that is metallic in the infrared. We show that a reversibly switchable particle-on-mirror geometry can be created by locally switching the IST under the polystyrene microspheres. Measuring the light-scattering spectra of single polystyrene microspheres before and after crystallization and reamorphization, we observe huge shifts of the resonance wavelength, e.g., from 5.2 to 8.9 μm and back for 6 μm diameter spheres. Our work is a first step toward a controlled tuning of multipolar Mie modes of various particles using reprogrammable IST mirror structures.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"1 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2026-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}