Review
Chemistry, Multidisciplinary
Yoshihiro Kangawa, Akira Kusaba, Pawel Kempisty, Kenji Shiraishi, Shugo Nitta, Hiroshi Amano
Summary: In order to control semiconductor epitaxy, it is necessary to conduct sequential analysis of all elementary growth processes and promote the development of an accurate integrated crystal growth model. This model, based on first-principles calculations, can predict changes in carbon concentration during epitaxy processes and provide important references for solving innovation issues in the semiconductor manufacturing industry.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Physics, Multidisciplinary
Wenhui Wan, Na Kang, Yanfeng Ge, Yong Liu
Summary: In this study, the structural and magnetic properties of Si-doped bulk and 2D AlN were systematically investigated. It was found that Si atoms prefer to substitute Al atoms in both bulk and 2D AlN, and their behavior differs under different conditions. The results also suggest that 2D AlN doped with group IV elements has potential applications in spintronic devices.
FRONTIERS IN PHYSICS
(2022)
Correction
Chemistry, Multidisciplinary
Yusen Qiao, Huabing Yin
Summary: This article presents a correction for the ferromagnetic and half-metallic phase transition in a one-dimensional narrow-bandgap W6PCl17 semiconductor through doping.
Article
Engineering, Chemical
Sungil Yun, Feiyang Ou, Henrik Wang, Matthew Tom, Gerassimos Orkoulas, Panagiotis D. Christofides
Summary: Atomistic simulations using density functional theory and a kinetic Monte Carlo method were used to investigate the area-selective atomic layer deposition (ASALD) process with the integration of small-molecule inhibitors (SMIs) for improved regioselectivity of thin-layer deposition. The simulation results were in good agreement with experimental findings.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Materials Science, Multidisciplinary
Ling Niu, Jianmei Du, Xu Tian, Daochuan Jiang, Lina Gu, Yupeng Yuan
Summary: In this study, S-doped g-CN nanosheets were successfully synthesized via a steam activation route, which exhibited enhanced visible light absorption ability and surface area. The resulted g-CN-TM1 showed significantly improved performance in photocatalytic H-2 generation compared to pristine g-CN.
Article
Chemistry, Multidisciplinary
Avto Tavkhelidze, Amiran Bibilashvili, Larissa Jangidze, Nima E. Gorji
Summary: Recent study observed geometry-induced quantum effects in periodic nanostructures, particularly in Silicon NG layers. The Fermi-level tuning of G-doped layers by changing NG depth was investigated, showing a significant increase in the Fermi level at 10 nm depth, with decreasing effects in p- and n-type substrates. The results were explained using the G-doping theory and G-doped layer formation mechanism introduced in previous works.
Article
Energy & Fuels
Nithin Thomas Jacob, Jeroen Lauwaert, Bart Vermang, Johan Lauwaert
Summary: Carbon capture and utilization (CCU) is a promising solution to reduce reliance on fossil fuels by using effective photo/electrocatalysts. Direct Z-scheme heterojunctions, simulating photosynthesis in plants, use sunlight for various photocatalytic reactions. This study proposes a method to model direct Z-scheme junctions in a solar cell simulator and discusses the impact of defects on the performance of the junction.
Article
Engineering, Electrical & Electronic
Yuxing Zhou, Wei Zhang, En Ma, Volker L. Deringer
Summary: This study presents a machine-learning-based potential model that can simulate phase-change materials, including germanium-antimony-tellurium compositions, under realistic device conditions. The model's speed allows for atomistic simulations of multiple thermal cycles and complex operations, making it potentially valuable for neuro-inspired computing.
NATURE ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Yuxing Zhou, Wei Zhang, En Ma, Volker L. Deringer
Summary: Computer simulations are important for understanding phase-change materials and developing memory technologies, but there are limitations in directly simulating with quantum mechanics. In this study, a machine-learning-based potential model was trained using quantum-mechanical data to simulate a range of compositions of phase-change materials under realistic device conditions. The model allows for atomistic simulations of multiple thermal cycles and delicate operations for neuro-inspired computing.
NATURE ELECTRONICS
(2023)
Article
Chemistry, Multidisciplinary
Andreij C. Gadelha, Viet-Hung Nguyen, Eliel G. S. Neto, Fabiano Santana, Markus B. Raschke, Michael Lamparski, Vincent Meunier, Jean-Christophe Charlier, Ado Jorio
Summary: This study investigates the importance of phonons in twisted-bilayer graphene at the magic-angle using gate-dependent micro-Raman spectroscopy. The results reveal that the unique electronic structure at the magic-angle influences the electron-phonon coupling, resulting in a larger G band line width.
Article
Chemistry, Multidisciplinary
Jinming Xue, Bo Wang, Ziqiang Li, Zongbo Xie, Zhanggao Le
Summary: This study utilized NH4Br as a source of bromide to conduct bromine doping in g-C3N4, aiming to enhance its light absorption and efficiency in photocatalytic reduction of uranium. The resulting materials demonstrated a smaller band gap, indicating an extended light absorption range. Compared to bulk carbon nitride, the efficiency of photocatalytic reduction of uranium was increased by 2.2 times, with good stability over five cycles.
RESEARCH ON CHEMICAL INTERMEDIATES
(2022)
Article
Chemistry, Physical
Osung Kwon, Yoon Kim, Myounggon Kang, Sungjun Kim
Summary: The study analyzed Cu/SiN/SiO2/Si devices with different dopant concentrations to be used in neuromorphic systems, revealing distinct resistive switching behavior under various operating conditions. Among them, the Cu/SiN/SiO2/p(+)-Si device showed more suitable characteristics for synaptic applications.
APPLIED SURFACE SCIENCE
(2021)
Article
Physics, Condensed Matter
Yun Kang, Le Chen, Caiyun Liu, Xuemei Tang, Xingrui Zhu, Wei Gao, Hong Yin
Summary: In this study, the enhancement of n-type conductivity of nanocrystalline hexagonal boron nitride (h-BN) films with simultaneous incorporation of Si and O was reported, which effectively healed nitrogen vacancy (V-N) defects and significantly reduced electric resistivity in h-BN thin films.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Chemistry, Physical
Jing Luo, Ming Yan, Haiyan Ji, Liping Mu, Yan Huang, Linhua Zhu, Yiru Zou, Chao Wang, Peiwen Wu, Yanhong Chao, Wenshuai Zhu
Summary: This study successfully synthesized Ce@C-BN materials through a direct pyrolysis strategy, which exhibited high specific surface area and excellent adsorption performance for desulfurization. The presence of Ce-MOFs not only provided active sites but also enhanced the interaction between Ce and BN.
APPLIED SURFACE SCIENCE
(2022)
Article
Engineering, Environmental
Amarachi Udoka Nkwoada, Gerald Onyedika, Emeka Oguzie, Martin Ogwuegbu
Summary: A new-fangled PSA@PS-TiO2 photocatalyst was fabricated using periwinkle shell ash (PSA) and polystyrene (PS). The morphological images of all samples showed a size distribution of 50-200 nm. The PSA@PS-TiO2 exhibited better photocatalytic efficiency for methyl orange degradation due to its rough surface morphology, main crystal phases of TiO2, low bandgap, and beneficial functional groups.
WATER SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
A. Parisi, F. Tesolin, M. Mercandelli, L. Bertulessi, A. L. Lacaita
Summary: This study introduces a compact self-biasing dynamic startup circuit for class-C voltage-controlled oscillators, achieving excellent startup time and extremely small area.
IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Francesco Buccoleri, Andrea Bonfanti, Andrea L. Lacaita
Summary: This paper presents novel equations to describe the dependence of oscillation frequency on harmonic content in differential oscillators, rigorously considering the effect of common-mode oscillation. The inclusion of an additional term related to transistor current on drain voltage is disclosed for the first time, showing dominance in ohmic operation. Results obtained from applying this framework to Van der Pol oscillators in 28-nm bulk CMOS technology match well with detailed circuit simulations. The analysis reveals that the classical theory may not account for close-in phase noise performance when even harmonics are relevant, while the novel theoretical framework justifies the simulation results and explores new mechanisms of flicker noise up-conversion in the considered oscillator structures.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2021)
Article
Engineering, Electrical & Electronic
Mario Mercandelli, Alessio Santiccioli, Angelo Parisi, Luca Bertulessi, Dmytro Cherniak, Andrea L. Lacaita, Carlo Samori, Salvatore Levantino
Summary: This article introduces a novel fractional-N sampling type-I phase-locked loop (PLL) with digital phase error correction (DPEC) and frequency locking method, which provides low jitter performance, fast lock, low spurs, and power consumption, while occupying a small area.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2022)
Article
Engineering, Electrical & Electronic
Luca Bertulessi, Dmytro Cherniak, Mario Mercandelli, Carlo Samori, Andrea L. Lacaita, Salvatore Levantino
Summary: This paper presents a novel technique to reduce locking time in a Digital Phase-Locked Loop (DPLL) based on Bang-Bang Phase Detector (BB-PD), improving the trade-off between phase noise and locking time. The implemented CMOS fractional-N frequency synthesizer demonstrates low output signal spot noise and a fast locking time, overcoming limitations and cycle slips associated with 1-bit phase detector PLLs.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2022)
Article
Engineering, Electrical & Electronic
Gerardo Malavena, Mattia Giulianini, Luca Chiavarone, Alessandro S. Spinelli, Christian Monzio Compagnoni
Summary: In this research, it is shown through experiments that a high-temperature idle/data-retention phase leads to a permanent intensification of random telegraph noise (RTN) in 3-D NAND Flash arrays. The effect is explained by the depassivation of traps at grain boundaries during the high-temperature phase, resulting in nonuniformities in channel inversion and an increased number of active defects in the RTN process.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Alessandro Garghetti, Andrea L. Lacaita, David Seebacher, Matteo Bassi, Salvatore Levantino
Summary: This study analyzes harmonic generation in ring-based injection-locked frequency dividers, presenting a novel divide-by-five ILFD that significantly broadens locking range through reinforced multi-injection. The implemented stage operates over a wide frequency range with good power consumption efficiency, achieving the highest operating frequency among current CMOS ILFDs.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2022)
Article
Engineering, Electrical & Electronic
Simone M. Dartizio, Francesco Tesolin, Mario Mercandelli, Alessio Santiccioli, Abanob Shehata, Saleh Karman, Luca Bertulessi, Francesco Buccoleri, Luca Avallone, Angelo Parisi, Andrea L. Lacaita, Michael P. Kennedy, Carlo Samori, Salvatore Levantino
Summary: This work introduces a new bang-bang fractional-N phase-locked loop with quantization noise shaping that overcomes the noise limit of a standard phase detector. An adaptive algorithm ensures optimal noise shaping across process and environmental variations. The prototype, implemented in a standard 28-nm CMOS process, achieves low jitter power consumption and high performance in different channel configurations.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2022)
Article
Physics, Applied
M. Dossena, G. Malavena, A. S. Spinelli, C. Monzio Compagnoni
Summary: This paper presents a comprehensive modeling investigation of the Pt/BaTiO3/Nb:SrTiO3 stack designed as a Ferroelectric Tunnel Junction (FTJ), with a focus on specific material features often overlooked. The analysis includes validation through a consistent comparison with experimental data, exploring the resistive memory window of the FTJ, and providing insights for the development of next-generation memory technologies based on FTJ.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Gabriele Be, Angelo Parisi, Luca Bertulessi, Luca Ricci, Lorenzo Scaletti, Mario Mercandelli, Andrea L. Lacaita, Salvatore Levantino, Carlo Samori, Andrea Bonfanti
Summary: This paper presents a 12-bit SAR-based TI-ADC with a fully programmable interleaving factor, achieving low interleaving spurs and high SNDR at different configurations. The ADC demonstrates good performance metrics and low power dissipation at 900MS/s.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS
(2022)
Article
Engineering, Electrical & Electronic
Giacomo Castoro, Simone M. Dartizio, Andrea L. Lacaita, Salvatore Levantino
Summary: The paper provides a detailed analysis of phase noise in periodically switched oscillators (PSOs) and shows that their output phase noise cannot be estimated using the analogy to retimed oscillators. The authors derive closed form expressions for the transfer of both the reference and the oscillator noise, including a correction for the contribution of the oscillator close-in phase noise. The results are validated through simulations and the excess noise arising from the on-off transients is also discussed.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2023)
Article
Engineering, Electrical & Electronic
Mattia Giulianini, Gerardo Malavena, Christian Monzio Compagnoni, Alessandro S. Spinelli
Summary: This paper presents a detailed analysis of the time dynamics of the down-coupling phenomenon (DCP) in 3-D NAND Flash memory strings. The transient time dynamics of the channel potential following the wordline (WL) bias transition from the pass voltage to zero is studied via numerical simulation. The results highlight the existence of three temporal regimes controlled by different physical processes and can be used as a design guideline for NAND strings.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Francesco Tesolin, Simone M. Dartizio, Francesco Buccoleri, Alessio Santiccioli, Luca Bertulessi, Carlo Samori, Andrea L. Lacaita, Salvatore Levantino
Summary: An LO phase-shifting system based on digital fractional -N bang-bang phase-locked loops (PLLs) in the 8.5-10.0-GHz range is presented. The system leverages a direct phase modulation method to perform LO phase-shifting within the frequency synthesizer, achieving inherently linear phase-shifting characteristic. The synchronization between fractional -N PLL cores is achieved by clocking with the same reference clock.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2023)
Article
Engineering, Electrical & Electronic
Simone M. Dartizio, Francesco Tesolin, Giacomo Castoro, Francesco Buccoleri, Michele Rossoni, Dmytro Cherniak, Carlo Samori, Andrea L. Lacaita, Salvatore Levantino
Summary: This work presents a solution for a low-spur and low-jitter fractional-N digital phase-locked loop (PLL). The use of an inverse-constant-slope DTC and a frequency-control-word subtractive dithering technique effectively reduces the fractional spurs caused by non-linearity and improves system performance.
IEEE JOURNAL OF SOLID-STATE CIRCUITS
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
G. Malavena, J. L. Mazzola, M. Greatti, C. Monzio Compagnoni, A. L. Lacaita, V Marano, M. Lauria, D. Paci, E. Speroni, A. S. Spinelli
Summary: This study investigates the statistical spread of Time-Dependent Dielectric Breakdown (TDDB) in thick polymeric dielectrics for galvanic isolation devices. By conducting Monte Carlo simulations and introducing inhomogeneities in the material properties, the experimental TDDB spread is successfully reproduced. The findings of this study have important implications for the design and use of galvanic isolation devices.
2022 IEEE LATIN AMERICAN ELECTRON DEVICES CONFERENCE (LAEDC)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Angelo Parisi, Mario Mercandelli, Carlo Samori, Andrea L. Lacaita
Summary: The novel technique utilizes numerical Phase-Locked Loops (NPLLs) to autonomously generate a distortion-less replica of the input signal and adaptively estimate polynomial correction via filters, significantly improving ADC performance.
2021 28TH IEEE INTERNATIONAL CONFERENCE ON ELECTRONICS, CIRCUITS, AND SYSTEMS (IEEE ICECS 2021)
(2021)
