Article
Chemistry, Multidisciplinary
Chia-You Liu, Kai-Ying Tien, Po-Yuan Chiu, Yu-Jui Wu, Yen Chuang, Hsiang-Shun Kao, Jiun-Yun Li
Summary: TFETs are considered as a promising choice for low-power applications due to their steep subthreshold swing, and research progress in GeSn Esaki diodes is expected to enhance the performance of TFETs.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Chithraja Rajan, Omdarshan Paul, Dip Prakash Samajdar, Tarek Hidouri, Samia Nasr
Summary: This study investigates the performance of Hetero Material (HM) tunnel FETs (TFETs) with a combination of ferroelectric (FE) HfZrO2 and dielectric (DE) SiO2. The presence of negative capacitance (NC) improves the electric field at the tunnel junction, leading to a reduced threshold voltage (V-th). By utilizing a suitable combination of different III-V and IV semiconductors, the ON current (I-ON) and subthreshold swing (SS) of the HM-TFETs are significantly improved compared to conventional TFETs. The results show that the Ge/GaAs based device exhibits higher energy efficiency and superior performance.
Article
Engineering, Multidisciplinary
Ahmed Shaker, Islam Sayed, Mohamed Abouelatta, Wael Fikry, S. Marwa Salem, Mohamed El-Banna
Summary: Accurate physically based models of TFETs are highly required for analyzing and predicting their device characteristics in circuits. This study focused on the physics-based modeling of InAs-based TFETs and showed that the electrostatic potential in these devices should depend on biasing conditions, contrary to Si-based TFETs. The interpretation of the electron quasi-Fermi potential (eQFP) correctly predicts the electrostatic potential and the drain-to-source band to band tunneling current.
AIN SHAMS ENGINEERING JOURNAL
(2023)
Article
Materials Science, Ceramics
Lingling Wu, Cuiping Guo, Ruohan Feng, Haoyue Zhang, Nan Shi, Yao Li, Huilan Su, Xinjiang Cui, Fang Song
Summary: This study successfully enhanced the visible light absorption and solar photocatalytic efficiency of TiO2 by codoping phosphonis(V) and Titanium(III) into leaf-architectured TiO2 via a sol-gel biotemplating approach. The codoping strategy led to a 2.6 times higher solar photocatalytic degradation rate compared to commercial TiO2 P25.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Engineering, Electrical & Electronic
Wei-Chih Hou, Pao-Chuan Shih, Hao-Hsiung Lin, Barry Bing-Ruey Wu, Jiun-Yun Li
Summary: In this study, InAs/GaSb heterojunction Esaki diodes with a high peak current density of 9 MA/cm(2) were demonstrated to exhibit negative differential resistance (NDR) from 300 to 4 K. The dominant transport mechanism was shown to be band-to-band tunneling (BTBT), with the peak current increasing due to higher doping concentrations. The research also proposed a model of tunneling enhancement near the mesa sidewalls by surface defects induced during dry etching, emphasizing the importance of careful processing steps to avoid overestimation of the BTBT current.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Nanoscience & Nanotechnology
Fan Cui, Yunyan Zhang, H. Aruni Fonseka, Premrudee Promdet, Ali Imran Channa, Mingqing Wang, Xueming Xia, Sanjayan Sathasivam, Hezhuang Liu, Ivan P. Parkin, Hui Yang, Ting Li, Kwang-Leong Choy, Jiang Wu, Christopher Blackman, Ana M. Sanchez, Huiyun Liu
Summary: The use of a thin layer of TiO2 deposited by atomic layer deposition can provide robust protection to III-V semiconductor nanowires, enhancing both their stability and performance in water-splitting applications. The protected nanowires showed improved photoluminescence intensity retention, higher photocurrent density, and a record-long highly stable performance compared to unprotected counterparts, demonstrating the effectiveness of the TiO2 layer as a protective coating.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Changming Ke, Yihao Hu, Shi Liu
Summary: Using first-principles calculations, we demonstrate the softening of unswitchable wurtzite III-V semiconductors at the nanoscale, resulting in ultrathin two-dimensional sheets with reversible polarization states. We identify a three-atomic-layer AlSb sheet that exhibits both ferroelectricity and antiferroelectricity, with tristate switching accompanied by a metal-semiconductor transition. Phonon spectrum calculations, ab initio molecular dynamics simulations, and variable-composition evolutionary structure search confirm the thermodynamic stability and potential synthesis of this triatomic layer. We propose a 2D AlSb-based homojunction field effect transistor that supports three distinct and nonvolatile resistance states, enabling nonvolatile multibit-based integrated nanoelectronics.
NANOSCALE HORIZONS
(2023)
Article
Physics, Applied
Philip C. Klipstein
Summary: In a photodiode made from a narrow bandgap III-V material such as InSb, the dominant dark current mechanism is thermal generation-recombination in the depletion region. XBn or XBp barrier detectors suppress the generation-recombination current by using a wide bandgap barrier material. Diffusion limited barrier detectors have a unity gain device architecture that is fundamentally different from traditional photodiodes. High performance barrier detector arrays for mid- and long-wave infrared detection have been developed using bulk alloy and type II superlattice (T2SL) absorbers.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Wei Yu, Zhaofu Zhang, Xuhao Wan, Hailing Guo, Qingzhong Gui, Yuan Peng, Yifei Li, Wenjie Fu, Dingyi Lu, Yuchen Ye, Yuzheng Guo
Summary: Density functional theory (DFT) is a powerful computational tool for electronic structure calculations of materials. DFT + U + V is an alternative approach that can overcome the limitations of accuracy and efficiency. In this study, we propose the use of Bayesian optimization with a dropout (BOD) algorithm to optimize the U and V terms, resulting in improved electronic properties for bulk materials at a lower computational cost. We also observe that U/V parameters are reasonably transferable between surface slabs and interfaces, allowing for accurate electronic property calculations of large-scale systems.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Physics, Applied
Mithun Bhowmick, Haowen Xi, Bruno Ullrich
Summary: This article introduces a model that accurately fits the absorption saturation parameter linked to the effective electron density of states, allowing for the comparison of experimentally found absorption limits and their variations in compound semiconductors with theoretical expectations. This is crucial for certain optoelectronic device applications.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Trupti K. Gajaria, Narayan N. Som, Shweta D. Dabhi, Prafulla K. Jha
Summary: This article introduces the study of III-V materials, focusing on the electronic dispersion and band alignment of heterostructure nanowires. The results show that these materials have potential applications in photocatalysis and photovoltaics, and exhibit good catalytic activity in the hydrogen evolution reaction. Additionally, the nano-scale nature of these systems offers cost-effective production advantages.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Nanoscience & Nanotechnology
Joseph Sink, Craig Pryor
Summary: Suitable tight-binding models for wurtzite III-V (non-nitride) and group-V materials are currently lacking in literature. Existing models for cubic-zincblende semiconductors result in inaccurate band structures for hexagonal polytypes. Wurtzite parameters are useful for modeling nanowires condensing into either wurtzite or zincblende phases. We have developed spds tight-binding parameters for wurtzite crystal phase in non-nitride III-V and group V semiconductors, which, when combined with zincblende parameters, allow for modeling heterostructures with both crystal phases.
Article
Chemistry, Physical
Maciej J. Winiarski
Summary: This study investigated the electronic structures of ternary alloys of group III and rare earth nitrides, revealing that the introduction of rare earth ions can affect the band gap width. The findings suggest potential applications of these materials, encouraging further experimental investigations.
Article
Engineering, Electrical & Electronic
K. Vanlalawmpuia, Aditya Sankar Medury
Summary: In this article, the impact of ferroelectric layer thickness (tFE) on the electrical parameters of a negative capacitance dual stacked-source tunnel field-effect transistor (NCDSS-TFET) is systematically investigated using TCAD simulator. Increasing tFE leads to higher ION/IOFF current ratio and better subthreshold swing (SS) with negligible hysteresis. However, it also introduces negative differential resistance (NDR) which is undesirable for analog circuit applications. The NCDSS-TFET device is further optimized to eliminate NDR effects by engineering the drain. The analog/RF performance of the drain-engineered NCDSS-TFET is investigated and found to be improved by increasing the drain underlap length, making it suitable for high-performance and ultralow power analog applications.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Energy & Fuels
S. Catalan-Gomez, E. Martinez Castellano, M. Schwarz, M. Montes Bajo, L. Dorado Vargas, A. Gonzalo, A. Redondo-Cubero, A. Gallego Carro, A. Hierro, J. M. Ulloa
Summary: This study investigates the use of core-shell gallium nanoparticles as functional light scatterers on solar cells. By optimizing the nanoparticle size, the short-circuit current of the solar cells is significantly improved. The underlying physical mechanism is studied through optical measurements and simulations, and a method to reduce the plasmonic effect of the nanoparticles is demonstrated.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2024)
Article
Engineering, Electrical & Electronic
Zhicheng Wu, Jacopo Franco, Anne Vandooren, Philippe Roussel, Ben Kaczer, Dimitri Linten, Nadine Collaert, Guido Groeseneken
Summary: Low thermal budget junction-less transistors with back-gate were fabricated for 3-D sequential integration. The study showed that back-gate bias can modulate carrier mobility and BTI reliability. Applying back-gate bias during ON-state can adjust device performance without reliability penalty, while applying it during both ON- and OFF-states can improve BTI reliability without performance loss.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Engineering, Electrical & Electronic
Wei-Min Wu, Ming-Dou Ker, Shih-Hung Chen, Arturo Sibaja-Hernandez, Sachin Yadav, Uthayasankaran Peralagu, Hao Yu, AliReza Alian, Vamsi Putcha, Bertrand Parvais, Nadine Collaert, Guido Groeseneken
Summary: Gallium nitride (GaN) technologies play an important role in commercial advanced RF systems, but face challenges in reliability due to electrostatic discharge (ESD). A mis-correlation between standard-defined human body model (HBM) ESD robustness and commonly used transmission line pulse (TLP) failure current was observed in GaN high electron mobility transistors (HEMTs). A discharge model is proposed to explain the mechanism, and simulations confirm that the mis-correlation is due to 2-dimensional electron gas (2DEG) resistance modulation in response to HBM ESD transient voltage waveforms.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Zhicheng Wu, Jacopo Franco, Anne Vandooren, Hiroaki Arimura, Lars-Ake Ragnarsson, Philippe Roussel, Ben Kaczer, Dimitri Linten, Nadine Collaert, Guido Groeseneken
Summary: This article proposes a method to improve the reliability of high-k/metal gate structures by inserting defect decoupling layers between SiO2 and HfO2. The study shows that LaSiOx has little impact on carrier mobility, while Al2O3 can improve both positive and negative BTI reliability. Furthermore, the simplified dual gate-stack integration strategy is explored, indicating that the pMOS gate-stack is more tolerant to the presence of a residual LaSiOx layer.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Multidisciplinary Sciences
Frederic Vanderveken, Vasyl Tyberkevych, Giacomo Talmelli, Bart Soree, Florin Ciubotaru, Christoph Adelmann
Summary: A lumped circuit model for inductive antenna spin-wave transducers in the vicinity of a ferromagnetic medium is derived in this paper. The model takes into account the antenna's resistance, inductance, as well as the additional inductance due to the excitation of ferromagnetic resonance or spin waves. Using a wire antenna on top of a ferromagnetic waveguide as an example, the additional inductance is discussed, along with the scaling properties and energy efficiency of inductive antennas.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Applied
Emeric Deylgat, Sabyasachi Tiwari, William G. Vandenberghe, Bart Soree
Summary: Topological insulators have unique properties that make them promising for next-generation electronic devices. Passivating stanene nanoribbons is necessary for their implementation in devices. We develop a tight-binding model based on the Kane-Mele model and show its agreement with density functional theory calculations, capturing the physics of passivated edge bands.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Wen-Chieh Chen, Shih-Hung Chen, Thomas Chiarella, Geert Hellings, Dimitri Linten, Guido Groeseneken
Summary: The electrostatic discharge (ESD) reliability of OFF- and ON-state NMOS field-effect transistors in a bulk FinFET technology is investigated in this study. The study focuses on the impacts of gate pitch (GP) and gate length (L-g) on the epitaxy of source and drain regions. It is found that a large GP leads to nonuniform epitaxy and high power density localization in the device, while a large L-g improves the ESD performance. Additionally, the study reveals that the clamping voltage and ON-resistance of the ON-state NMOSFET are influenced by L-g and GPs, with shorter L-g and the same gate space achieving better ESD performance.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
M. Vandemaele, B. Kaczer, S. Tyaginov, J. Franco, E. Bury, A. Chasin, A. Makarov, G. Hellings, G. Groeseneken
Summary: We simulate the spatial profile of trapped charge in the forksheet FET wall under hot-carrier stress and find that the charge trapping occurs above and below the horizontal projection of the sheet. The charge profile is independent of the sheet width, and the trapping in the forksheet FET wall is significantly smaller than the trapping in the gate stack.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Emeric Deylgat, Edward Chen, Massimo Fischetti, Bart Soree, William G. Vandenberghe
Summary: This study compares the contact resistance and image-force barrier lowering (IFBL) for four different metal-dielectric-two-dimensional (2D) material configurations. The analysis considers different geometries of edge contacts and calculates the contact resistivity using the WKB approximation. The optimal configuration achieves a 50-fold reduction in contact resistance compared to the situation without considering IFBL.
SOLID-STATE ELECTRONICS
(2022)
Article
Physics, Applied
Sabyasachi Tiwari, Maarten L. Van de Put, Kristiaan Temst, William G. Vandenberghe, Bart Soree
Summary: To design fast memory devices, the combination of a two-dimensional (2D) magnet and a 2D topological insulator (TI) is proposed as a viable option. The spin-charge dynamics between 2D magnets and 2D TIs are theoretically modeled using the adiabatic approximation. It is shown that magnetic domains of a ferromagnet can be switched using the spin torque from spin-polarized edge states of a 2D TI, and the switching is strongly dependent on the interface exchange.
PHYSICAL REVIEW APPLIED
(2023)
Article
Engineering, Electrical & Electronic
Wei-Min Wu, Shih-Hung Chen, Chun-An Shih, Bertrand Parvais, Nadine Collaert, Ming-Dou Ker, Tian-Li Wu, Guido Groeseneken
Summary: Gallium nitride (GaN)-on-Si technologies for advanced RF applications have been drawing attention in the semiconductor industry, along with challenges in RF electrostatic discharge (ESD) reliability. Investigating both positive and negative ESD stress polarities is equally important. In this study, four scenarios of positive and negative human body model (HBM) stresses were conducted on GaN-on-Si (MIS-HEMTs) with gate-tied-to-source and gate-tied-to-drain configurations. It was found that the negative GS MIS-HEMT exhibited a failure mechanism different from the constant-power 2DEG failure mechanism in the typical positive GS (MIS-HEMT).
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Engineering, Electrical & Electronic
K. Kaczmarek, M. Garcia Bardon, Y. Xiang, N. Ronchi, L. -A. Ragnarsson, U. Celano, K. Banerjee, B. Kaczer, G. Groeseneken, J. Van Houdt
Summary: We investigate the origins of threshold voltage (V-TH) variability in planar ferroelectric FETs (FeFETs) by considering both process variations and source-drain channel percolation. By using a percolation-aware physics-based multidomain FeFET model, we are able to accurately capture the measured V-TH statistics across various channel dimensions in fabricated devices. Our findings suggest that the bimodal V-TH distribution observed in large devices can be explained by percolation, while the transition to a monomodal distribution in scaled devices is qualitatively reproduced by the overlapping Pelgrom-type and percolative variabilities in the model. Furthermore, we demonstrate that the percolation-related FeFET V-TH variability is minimized when the channel aspect ratio is equal to 1 in terms of device geometry.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Proceedings Paper
Engineering, Multidisciplinary
Michiel Vandemaele, Ben Kaczer, Erik Bury, Jacopo Franco, Adrian Chasin, Alexander Makarov, Hans Mertens, Geert Hellings, Guido Groeseneken
Summary: We present TCAD simulation studies on the hot-carrier reliability of nanowire (NW), nanosheet (NS), and forksheet (FS) FETs. The simulations involve solving the Boltzmann transport equation, calculating interface state generation and bulk defect charging, and evaluating the impact of generated/trapped charges on FET characteristics. We discuss the models used in hot-carrier simulation flows, anneal measurements, and validate the simulation models by comparing with NW FET measurements, providing insights for NS and FS FETs.
2023 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM, IRPS
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
S. Abhinay, W. -M. Wu, C. -A. Shih, S. -H. Chen, A. Sibaja-Hernandez, B. Parvais, U. Peralagu, A. Alian, T. -L. Wu, M. -D. Ker, G. Groeseneken, N. Collaert
Summary: This paper presents an extensive experimental study and simulations on the impact of different stress scenarios on the ESD robustness of GaN RF HEMTs. The study highlights the importance of different current discharge paths for each stress scenario and verifies the contribution of the on-state gate Schottky diode to the robustness of the HEMTs. Additionally, three types of HBM failure mechanisms are identified under different stress scenarios.
2022 INTERNATIONAL ELECTRON DEVICES MEETING, IEDM
(2022)
Proceedings Paper
Engineering, Multidisciplinary
Michiel Vandemaele, Ben Kaczer, Stanislav Tyaginov, Erik Bury, Adrian Chasin, Jacopo Franco, Alexander Makarov, Hans Mertens, Geert Hellings, Guido Groeseneken
Summary: Forksheet (FS) FETs are a new transistor architecture that utilizes vertically stacked nFET and pFET sheets with a dielectric wall, reducing p-to-n separation. Hot-carrier degradation (HCD) simulations show that both FS FETs and NS FETs can reduce HCD with increasing sheet width when considering interface state generation. Furthermore, an initial assessment suggests that the impact of oxide defect charging in the FS wall can be controlled under operating conditions.
2022 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM (IRPS)
(2022)
Proceedings Paper
Engineering, Multidisciplinary
Ping-Yi Hsieh, Artemisia Tsiara, Barry O'Sullivan, Didit Yudistira, Marina Baryshnikova, Guido Groeseneken, Bernardette Kunert, Marianna Pantouvaki, Joris Van Campenhout, Ingrid De Wolf
Summary: This study reports for the first time a reliability study on degradation of InGaAs/GaAs nano-ridge p-i-n diodes monolithically integrated on Si by nano-ridge engineering (NRE). The results show that current crowding and Joule heating near the p-contact are responsible for the degradation in forward bias region, while the electrical stress-induced leakage current indicates the degradation of crystal quality in reverse bias region. The study also demonstrates that a sintering process can lower the p-contact resistance and improve electrical stability, and the high aspect-ratio of the trenches leads to effective threading dislocation trapping.
2022 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM (IRPS)
(2022)
