Abstract Memtransistors are active analog memory devices utilizing ionic memristive materials as channel layers. Since their introduction, the term “memtransistor” has widely been adopted for transistors exhibiting nonvolatile memory characteristics. Currently, memtransistor devices possessing both transistor on/off functionality and nonvolatile memory characteristics include ferroelectric field‐effect transistors (FeFETs) and charge‐trap flash (floating gate), yet ionic memtransistors have not matched their performance. Here a facile and extendable lithium (Li)‐well oxide memtransistor (LWOM) is reported as a promising candidate. Forming a Li well, analogous to an n + well beneath electrodes in n‐metal‐oxide‐semiconductor field‐effect transistor (MOSFET) processes, induces Li⁺‐ion migration via write V DS , achieving analog memory characteristics through Schottky barrier modulation. LWOM enables low‐voltage weight updates and precise gate‐controlled weight update characteristics. Analysis via 3D secondary ion mass spectrometry (SIMS) confirms Li‐ion redistribution and the resistance‐switching mechanism. A 21 × 21 crossbar array demonstrates 99.31% operational yield and successful weight updates to target conductance values. Fabricated using mature oxide semiconductor technology with a 230 °C thermal budget and a simple process, LWOM stands as a strong contender for next‐generation nonvolatile memory and artificial neural network (ANN) acceleration hardware.

Abstract Inexpensive, high‐speed deposition techniques that ensure uniformity, scalability, wide applicability, and tunable thickness are crucial for the practical application of 2D materials. In this work, rapid drying is identified as a key mechanism for pioneering two high‐speed wet deposition methods: hot dipping and air knife sweeping (AKS). Both techniques allow thickness control proportional to flake concentration, achieving tiled monolayers and pinhole‐free coverage across the entire substrate, as long as evaporation outpaces flake diffusion. AKS prevents non‐uniformity along substrate edges by eliminating contact line pinning. The achieved deposition speed of 0.21 m 2 min −1 with AKS significantly surpasses traditional methods, enabling the equipment for large substrates > 1 m 2 . Combined with the ultralow debonding force for mechanically susceptible flexible display production and short‐circuit‐proof nanometer‐thin capacitors with capacitance comparable to commercial multilayer ceramic capacitors (MLCCs), these new protocols showcase simple and swift solutions for manufacturing 2D materials‐based nanodevices.

Abstract Memtransistors are active analog memory devices utilizing ionic memristive materials as channel layers. Since their introduction, the term “memtransistor” has widely been adopted for transistors exhibiting nonvolatile memory characteristics. Currently, memtransistor devices possessing both transistor on/off functionality and nonvolatile memory characteristics include ferroelectric field‐effect transistors (FeFETs) and charge‐trap flash (floating gate), yet ionic memtransistors have not matched their performance. Here a facile and extendable lithium (Li)‐well oxide memtransistor (LWOM) is reported as a promising candidate. Forming a Li well, analogous to an n + well beneath electrodes in n‐metal‐oxide‐semiconductor field‐effect transistor (MOSFET) processes, induces Li⁺‐ion migration via write V DS , achieving analog memory characteristics through Schottky barrier modulation. LWOM enables low‐voltage weight updates and precise gate‐controlled weight update characteristics. Analysis via 3D secondary ion mass spectrometry (SIMS) confirms Li‐ion redistribution and the resistance‐switching mechanism. A 21 × 21 crossbar array demonstrates 99.31% operational yield and successful weight updates to target conductance values. Fabricated using mature oxide semiconductor technology with a 230 °C thermal budget and a simple process, LWOM stands as a strong contender for next‐generation nonvolatile memory and artificial neural network (ANN) acceleration hardware.

Abstract Inexpensive, high‐speed deposition techniques that ensure uniformity, scalability, wide applicability, and tunable thickness are crucial for the practical application of 2D materials. In this work, rapid drying is identified as a key mechanism for pioneering two high‐speed wet deposition methods: hot dipping and air knife sweeping (AKS). Both techniques allow thickness control proportional to flake concentration, achieving tiled monolayers and pinhole‐free coverage across the entire substrate, as long as evaporation outpaces flake diffusion. AKS prevents non‐uniformity along substrate edges by eliminating contact line pinning. The achieved deposition speed of 0.21 m 2 min −1 with AKS significantly surpasses traditional methods, enabling the equipment for large substrates > 1 m 2 . Combined with the ultralow debonding force for mechanically susceptible flexible display production and short‐circuit‐proof nanometer‐thin capacitors with capacitance comparable to commercial multilayer ceramic capacitors (MLCCs), these new protocols showcase simple and swift solutions for manufacturing 2D materials‐based nanodevices.

Abstract Band engineering is an effective strategy to improve the electronic transport properties of semiconductors. In thermoelectric materials research, density‐of‐states effective mass is an undoubted key factor in verifying the band engineering effect and establishing a strategy for enhancing thermoelectric performance. However, estimation of the effective mass is demanding or inaccurate depending on the methods taken. A simple equation is proposed, valid for all degeneracy: Log 10 ( m d * T /300) = (2/3) Log 10 ( n ) − (2/3) [20.3 − (0.00508 × | S |) + (1.58 × 0.967 | S | )] that utilizes experimentally determined Seebeck coefficient ( S ) and carrier concentration ( n ) to determine the effective mass ( m d *) at a temperature ( T ). This straightforward equation, which gives an accurate analysis of the band modulation in terms of m d *, is indispensable in designing thermoelectric materials of maximized performance.

In this study, we report a systematic investigation of the dielectric properties and structural evolution of K(Ca₁₋ₓSrₓ)₂Nb₃O₁₀ and H(Ca₁₋ₓSrₓ)₂Nb₃O₁₀ layered perovskite ceramics (x = 0, 0.25, 0.5, 0.75, 1) to evaluate their potential for high-temperature multilayer ceramic capacitor (MLCC) applications. While BaTiO₃-based MLCCs suffer from dielectric instability above 120 °C, the proton-exchanged series H(Ca₁₋ₓSrₓ)₂Nb₃O₁₀ demonstrated stable temperature coefficient of capacitance (TCC) performance up to 200 °C, particularly for samples sintered at 1300 °C. Among them, HSr₂Nb₃O₁₀ (x = 1) exhibited the highest dielectric constant (>700 at 25 °C, 1 kHz) and exceptional TCC stability within ±15% across the full temperature range. Structural analysis revealed that sintering induces phase decomposition into stable binary niobates such as SrNb₂O₆ and Sr₂Nb₂O₇. Interestingly, the dielectric constants of the sintered HSr₂Nb₃O₁₀ ceramics exceeded the weighted average of their constituent phases. Transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD) analyses revealed that strain fields and high-angle grain boundaries introduced during phase decomposition are responsible for this enhancement. In particular, the localized tensile stress at grain boundaries in HSr₂Nb₃O₁₀ (x = 1) is suggested to promote high polarization regions, leading to improved dielectric performance. These findings highlight the role of strain engineering and multiphase interfaces in designing advanced dielectric ceramics for next-generation MLCCs.

This study investigates the thermoelectric properties of W-doped p-type Ge0.9Sb0.1Te thermoelectricmaterials using the Single Parabolic Band (SPB) model and conducts an analysis aimed at optimizingperformance at room temperature. GeTe, a type IV-VI chalcogenide semiconductor, has gained attention asa mid-temperature (600 ~ 900 K) thermoelectric material. GeTe-based alloys are particularly utilized as ptypethermoelectric materials at high temperatures. However, pure GeTe contains a high concentration of Gevacancies, leading to a high hole concentration, a low Seebeck coefficient, and high thermal conductivity,which inherently limit its thermoelectric performance. In this study, the density-of-states effective mass (md*),non-degenerate mobility (μ0), weighted mobility (μW), and B-factor were calculated for Ge0.9-xWxSb0.1Te (x =0.01-0.05) composites with varying W doping levels (x). Based on the calculations, the theoretical maximumzT and the optimal carrier concentration were derived. Experimental results confirmed that the optimal Wdoping concentration for maximizing thermoelectric performance at 325 K is x = 0.05. At this composition,due to band convergence, md* reached its peak. Given that the suppression of μ0 was less pronounced relativeto the increase in md*, a maximum μW value was obtained. Additionally, the lattice thermal conductivity (κlat)was minimized, and the B-factor reached its peak. The theoretical maximum zT at this composition wasapproximately 0.91 when nH was optimized to 3.29 × 1019 cm-3, representing a 106.8% increase compared tothe pristine phase (Ge0.9Sb0.1Te, ~0.44) and a 295.7% increase compared to the x = 0.05 composition reportedby Bayikadi et al. (Ge0.85W0.05Sb0.1Te, ~0.23). And this suggests that this composition has the potential to beutilized not only for conventional high-temperature power generation but also for active cooling applications.

Thermoelectric (TE) technology offers a sustainable solution that improves energy efficiency by converting waste heat into electrical energy. Among various thermoelectric materials, ZnSb has attracted attention due to its stable operation in the medium temperature range, its abundance, and its low cost. However, its simple crystal structure results in high ther- mal conductivity, which limits its thermoelectric performance. In this study, we doped Fe at the Zn sites to improve the electrical and thermal transport properties of ZnSb and analyzed the effects of Fe substitution. Fe Zny 1-ySb (y = 0, 0.001, 0.002, 0.004, and 0.006) compounds were synthesized via a melting-quenching-annealing process, and thermoelectric performance was evaluated according to Fe content. Low Fe doping significantly reduced lattice thermal conductivity by maximizing phonon scattering without significantly degrading electrical properties. The Fe0.002Zn0.998Sb sample exhibited an improved zT value of ~ 0.613 at 723 K, a 21% improvement over the ~ 0.507 value of pure ZnSb. These results pro- vide new insights into the enhancement of ZnSb thermoelectric properties through Fe doping and will contribute to the development of efficient and sustainable thermoelectric materials.

This review focuses on TSV-based bumpless hybrid bonding for AI semiconductors, covering metal passivation layers (Pt, Au, Ag, etc.) and surface activation techniques.

Fe-based dichalcogenides, captivating interest for their narrow 3d bands and potential as thermoelectric materials, have recently garnered attention. Park et al. reported enhanced zT of 0.18 for (Fe1-xCox )Te2 (x = 0.5) at 600 K, attributing it to the emergence of a fat band near the Fermi level. However, the infuence of alloying-induced band engineering and point defect-mediated phonon scattering remains elusive. Herein, we investigate the impact of compositional variation (x) on elec- tronic transport properties using the Single Kane Band model. Our analysis reveals predominant band convergence (x < 0.5) transitioning to band sharpening (x > 0.5). Notably, the weighted mobility, directly linked to the theoretical maximum power factor, exhibits a pronounced increase with increasing x. To evaluate the strength of phonon scattering by point defects, the Callaway-von Baeyer (CvB) model was employed. Surprisingly, the highest scattering parameter was not observed at x = 0.5 (maximum mixing) but at x = 0.25 and 0.75, signifying stronger phonon scattering at these compositions. Finally, considering the weighted mobility and lattice thermal conductivity, the theoretical maximum zT was calculated. Our fndings predict a potential enhancement of 118 times in zT for x = 0.75 (0.68) compared to the experimental value at x = 0 (0.005). This study underscores the signifcant potential for discovering novel, unexplored metal chalcogenide-based solid solutions with enhanced thermoelectric performance.