Article
Engineering, Electrical & Electronic
C. Navarro, L. Donetti, J. L. Padilla, C. Medina, J. Avila, J. C. Galdon, M. Recio, C. Marquez, C. Sampedro, F. Gamiz
Summary: The electrical performance of a novel reprogrammable FDSOI device with dual-doping at source/drain and only two top gates is investigated through advanced 3D TCAD simulations. The static and dynamic operations are evaluated and compared with those of traditional Schottky barrier RFETs and standard 28 nm FDSOI MOS transistors under manufacturable geometries.
SOLID-STATE ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Somesh Mane, Sandeep Semwal, Abhinav Kranti
Summary: This study introduces a simple and effective method to evaluate the resistance of various regions in reconfigurable field effect transistors (RFET) and extract key parameters, enabling accurate prediction of its performance characteristics.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Engineering, Electrical & Electronic
Jorge Navarro Quijada, Tim Baldauf, Shubham Rai, Andre Heinzig, Akash Kumar, Walter M. Weber, Thomas Mikolajick, Jens Trommer
Summary: Researchers propose a Verilog-A based Germanium nanowire table model for the analysis of dynamically reconfigurable logic gates. TCAD simulations of a nanowire transistor design are conducted, and performance and power consumption estimations for static and reconfigurable logic cells are provided. Results indicate performance improvements over Silicon nanowire-based designs, suggesting Germanium RFETs as promising candidates for integration into standard CMOS processes in the future.
IEEE TRANSACTIONS ON NANOTECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
T. Mikolajick, G. Galderisi, M. Simon, S. Rai, A. Kumar, A. Heinzig, W. M. Weber, J. Trommer
Summary: The reconfigurable field-effect transistor (RFET) is an electronic device that can reversibly reconfigure its conduction mechanism between n-type and p-type operation modes, relying on electrostatic doping instead of chemical doping. The focus of research has shifted towards the circuit level, bringing the unique device characteristics to fruition.
SOLID-STATE ELECTRONICS
(2021)
Article
Computer Science, Information Systems
Liu Xi, Ya Wang, Meile Wu, Lin Qi, Mengmeng Li, Shouqiang Zhang, Xiaoshi Jin
Summary: In this work, a high-performance nanoscale complementary low Schottky barrier nonvolatile bidirectional reconfigurable field effect transistor (CLSB-NBRFET) is proposed. It utilizes floating gates and dual metal silicide source/drain contacts to improve device performance and simplify interconnection complexity. The device size can be reduced to the nanoscale while maintaining high performance.
Article
Nanoscience & Nanotechnology
Lukas Wind, Raphael Behrle, Martien I. den Hertog, Corban G. E. Murphey, James F. Cahoon, Masiar Sistani, Walter M. Weber
Summary: In this work, bottom-up Al-Si-Al nanowire heterostructures are presented, which show promising potential for top-down fabricated nanosheet and multi-wire reconfigurable field-effect transistors. The transistors exhibit high symmetry in the key parameters of on- and off-currents and threshold voltages for n- and p-type operation, and also achieve low device-to-device variability. The investigated Al-Si material system is relevant for reconfigurable logic cells obtained from Si nanosheets. The Al-Si-Al platform has substantial potential for complex adaptive and self-learning circuits, energy efficient computing, small footprint, and hardware security circuits.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
C. Navarro, L. Donetti, J. L. Padilla, C. Medina-Bailon, J. C. Galdon, C. Marquez, C. Sampedro, F. Gamiz
Summary: Through 3D-TCAD simulations, this study demonstrates the advantages of Reconfigurable FETs based on dual doping with respect to the Schottky junctions counterparts using the 28 nm FDSOI platform. These devices with N and P dopant species at source and drain enable electron and hole symmetrical currents, resulting in larger currents and faster logic circuits. The dynamic results also reveal lower energy-delay products, making these devices more efficient and appealing for reprogrammable logic implementation.
SOLID-STATE ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Bin Sun, Benjamin Richstein, Patrick Liebisch, Thorben Frahm, Stefan Scholz, Jens Trommer, Thomas Mikolajick, Joachim Knoch
Summary: We investigated the operation modes of a dual-gate reconfigurable field-effect transistor (RFET) and compared the program gate at source (PGAS) with the more usual program gate at drain (PGAD) operation mode. We found that operating the RFET in PGAS mode yields a switching behavior close to a conventional MOSFET, but it needs to be traded off against strongly nonlinear output characteristics for small bias voltages. Our measurement results are supported by transport simulations employing a nonequilibrium Green's function approach.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Engineering, Electrical & Electronic
Xianglong Li, Xiaoqiao Yang, Zhe Zhang, Teng Wang, Yabin Sun, Ziyu Liu, Xiaojin Li, Yanling Shi, Jun Xu
Summary: The study reveals that control GER plays a dominant role in performance variation, while WFV dominates the variations of ON-state characteristics. The total overall performance fluctuations are primarily attributed to WFV.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Engineering, Electrical & Electronic
Junfeng Hu, Chao Wang, Yabin Sun, Ziyu Liu, Xiaojin Li, Yanling Shi
Summary: This article proposes a novel reconfigurable field-effect transistor called SSDRFET to improve the ON-state current. By surrounding the source and drain with a silicon channel and metal gate, a higher tunneling probability and gate control ability are achieved. The study investigates the performance under different geometry parameters and discusses the underlying physical mechanisms. The results show that selecting the size parameters carefully is crucial for achieving better performance. Furthermore, the reduced gate capacitance and improved ON-state current contribute to a more advantageous inverter based on SSDRFET, reducing about 70% of propagation delay.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Electrical & Electronic
Yabin Sun, Xianglong Li, Ziyu Liu, Yun Liu, Xiaojin Li, Yanling Shi
Summary: A novel tree-type channel reconfigurable field-effect transistor (RFET) is proposed to improve ON-state performance by introducing an additional interbridge (IB) channel. The study investigates the impact of geometry parameters and gate dielectric materials on threshold voltage (V-TH) and on-state current (I-ON), showing that a larger tunneling area provided by the large cross-sectional area of IB can enhance ON-state characteristics. Compared to conventional NS RFET, the tree-type RFET demonstrates significant improvements in ON-state current with specific width parameters and HfO2 gate dielectric, while suitable size parameters are necessary when using SiO2 gate dielectric due to tunneling strength issues. Discussion on the underlying physical mechanism is provided.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Junfeng Hu, Yabin Sun, Ziyu Liu, Xiaojin Li, Yanling Shi
Summary: In this article, a novel structure of reconfigurable field-effect transistor (RFET) with arch-shaped control gate (ASG)-RFET is presented. The ASG-RFET exhibits significant improvement in ON-state current and propagation delay. Through TCAD simulations, the impact of geometry parameters on the transistor performance and the current enhancement mechanism are investigated. It is found that the tunneling rate and tunneling area are increased significantly in the novel RFET, and the combined action of ON-state current and gate capacitance leads to a significant decrease in propagation delay.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Chemistry, Multidisciplinary
Gaotian Lu, Yang Wei, Xuanzhang Li, Ruixuan Peng, Guangqi Zhang, Zhen Mei, Liang Liang, Kai Liu, Qunqing Li, Shoushan Fan, Yuegang Zhang
Summary: This article introduces a reconfigurable carbon nanotube barristor based on a Schottky barrier CNT transistor, which exhibits significant rectifying characteristics and can be reconfigured to different rectifying modes by applying gate voltage. The reconfigurability comes from the ambipolar characteristics of the CNT channel, and the rectification behavior can be attributed to the drain-induced self-gating effect.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Sofia Zanella, Miguel A. Hernandez-Rodriguez, Lianshe Fu, Luis D. Carlos, Rute A. S. Ferreira, Carlos D. S. Brites
Summary: The miniaturization of silicon chips is nearing its physical limits and the small size of transistors causes current leakage, becoming an insurmountable problem. The world's excessive dependence on silicon is highlighted by the current chip shortage, emphasizing the need for silicon-free computing strategies. Quantum computing and computation using individual molecules are proposed as alternatives, with potential advantages in terms of miniaturization, performance enhancement, and energy efficiency. Molecular logics and the unique photonic characteristics of trivalent lanthanide ions have the potential to play a crucial role in the future of the computer industry.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Analytical
Tatyana E. Smolyarova, Lev Shanidze, Anna Lukyanenko, Filipp A. Baron, Vasilisa V. Krasitskaya, Anna S. Kichkailo, Anton S. Tarasov, Nikita Volkov
Summary: In this study, a top-down nanofabrication approach was used to create silicon nanowire-based back gate field-effect transistors for biomolecular detection. Physical mechanisms of charge carrier transport in the nanowire were explained using energy band diagrams and numerical simulations, which matched well with experimental results and can be applied to develop novel nanowire-based biosensors.
Review
Chemistry, Multidisciplinary
Thomas Mikolajick, Min Hyuk Park, Laura Begon-Lours, Stefan Slesazeck
Summary: Due to the low voltage driven switching and nonvolatility, ferroelectric materials have great potential for low power nonvolatile electronic devices. However, the incompatibility of well-known ferroelectrics with existing semiconductor technology has hindered the competitiveness of these devices. The discovery of ferroelectricity in hafnium oxide has changed this situation. This article summarizes the material science of ferroelectricity in hafnium oxide, discusses the status of nonvolatile ferroelectric memories, explores applications like in-memory computing, and showcases the realization of neuromorphic computing systems using basic building blocks of spiking neural networks.
ADVANCED MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
H. Alex Hsain, Younghwan Lee, Suzanne Lancaster, Patrick D. Lomenzo, Bohan Xu, Thomas Mikolajick, Uwe Schroeder, Gregory N. Parsons, Jacob L. Jones
Summary: By inserting a 1 nm Al2O3 layer at the HZO/TiN interface, a protective passivating layer is introduced, resulting in improved remanent polarization and endurance of TiN/HZO/TiN capacitors.
Article
Engineering, Electrical & Electronic
Tailang Xie, Claudia da Silva, Nadine Szabo, Thomas Mikolajick, Andre Wachowiak
Summary: This report investigates the influence of lateral edge termination on the drain leakage current in the off-state of vertical trench gate metal oxide semiconductor field effect transistors (MOSFETs), and presents a termination technology for achieving low leakage current.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Giulio Galderisi, Christoph Beyer, Thomas Mikolajick, Jens Trommer
Summary: Three-gated reconfigurable field-effect transistors have attracted significant interest in various fields due to their capability of n/p-type reconfiguration. Therefore, it is important to understand the temperature ranges in which these devices can operate and the underlying physical mechanisms. In this study, we conducted extensive observations on the operation of these devices in an ultrawide temperature range (80-475 K) and presented the results for their ambipolar and low VT operation modes. The data provided valuable insights into the temperature-dependent physical mechanisms governing the functionality of three-gated reconfigurable field-effect transistors.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2023)
Review
Physics, Applied
Phanish Chava, Zahra Fekri, Yagnika Vekariya, Thomas Mikolajick, Artur Erbe
Summary: This paper summarizes the application of two-dimensional materials in tunnel field effect transistors (TFETs), with a focus on heterojunctions made of different 2DMs. Various simulations and experimental devices are analytically studied to investigate different types, architectures, and tunneling mechanisms of the TFET technology. The main goal of this paper is to introduce the concept of tunneling in van der Waals devices and provide an overview of the recent progress and challenges in the field.
APPLIED PHYSICS REVIEWS
(2023)
Article
Engineering, Electrical & Electronic
J. Zhang, J. Reif, C. Strobel, P. Chava, A. Erbe, A. Voigt, T. Mikolajick, R. Kirchner
Summary: In recent years, research has focused on exploring smaller and smaller systems similar to micro/nano-robots. The main challenge in implementing these systems in the real world is the limited available volume. This paper introduces a folding technology using Al2O3 as the building material, which is compatible with current Si technology. The thin Al2O3 film is grown, patterned, thinned, and released from the Si substrate to create a free-standing Al2O3 structure that can fold itself at predefined regions. This technology offers a new possibility for efficiently utilizing volume by using Al2O3 as both the structural origami material and the functional gate dielectric material.
MICRO AND NANO ENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Sayantan Ghosh, Muhammad Bilal Khan, Phanish Chava, Kenji Watanabe, Takashi Taniguchi, Slawomir Prucnal, Rene Huebner, Thomas Mikolajick, Artur Erbe, Yordan M. Georgiev
Summary: This work introduces the concept of a mixed-dimensional reconfigurable field effect transistor (RFET) by combining a one-dimensional silicon nanowire with a two-dimensional hexagonal boron nitride (hBN) gate dielectric. The hBN encapsulation improves the device's electrical parameters, reducing hysteresis and increasing the on-off ratio. RFETs have great potential in reducing device count and power consumption, and the concept of mixed-dimensional RFET could further enhance their functionality.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Ruben Alcala, Monica Materano, Patrick D. Lomenzo, Pramoda Vishnumurthy, Wassim Hamouda, Catherine Dubourdieu, Alfred Kersch, Nicolas Barrett, Thomas Mikolajick, Uwe Schroeder
Summary: Ferroelectric hafnium-zirconium oxide is a promising material for next-generation non-volatile memory devices, but its performance reliability needs improvement. This study investigates the impact of different electrodes on the reliability metrics of endurance, retention, and imprint for Hf-Zr-based ferroelectric capacitors. It is found that the low reactivity of the electrode with the ferroelectric is crucial for improving device reliability. This understanding of interface properties will contribute to the development of next-generation memories.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Moritz Engl, Thomas Mikolajick, Stefan Slesazeck
Summary: This paper presents a measurement procedure to characterize the degradation of hysteresis free charge amplification in unipolar operation of negative capacitance capacitors. Two different degradation processes are identified, which are related to remanent switching of domains and a change in the electrical internal bias field.
SOLID-STATE ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Soundarya Nagarajan, Thomas Mikolajick, Jens Trommer
Summary: This study investigates the impact of boron dopant segregation on carrier density in silicon nanowires and ohmic contact formation. The results indicate that oxidation at high temperatures reduces the active carrier density, while dopant surface segregation during thermal formation enables low-resistance ohmic contacts.
SOLID-STATE ELECTRONICS
(2023)
Article
Chemistry, Multidisciplinary
Soundarya Nagarajan, Daniel Hiller, Ingmar Ratschinski, Dirk Konig, Sean C. Smith, Thomas Mikolajick, Jens Trommer
Summary: This paper presents the first experimental proof that doping of silicon nanowires can be achieved via the purposeful addition of aluminium-induced acceptor states. This alternative doping method can significantly reduce the resistance of silicon nanowires and lower the contact barrier height, potentially overcoming issues associated with doping and contact formation on the nanoscale.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Jose P. B. Silva, Ruben Alcala, Uygar E. Avci, Nick Barrett, Laura Begon-Lours, Mattias Borg, Seungyong Byun, Sou-Chi Chang, Sang-Wook Cheong, Duk-Hyun Choe, Jean Coignus, Veeresh Deshpande, Athanasios Dimoulas, Catherine Dubourdieu, Ignasi Fina, Hiroshi Funakubo, Laurent Grenouillet, Alexei Gruverman, Jinseong Heo, Michael Hoffmann, H. Alex Hsain, Fei-Ting Huang, Cheol Seong Hwang, Jorge Iniguez, Jacob L. Jones, Ilya V. Karpov, Alfred Kersch, Taegyu Kwon, Suzanne Lancaster, Maximilian Lederer, Younghwan Lee, Patrick D. Lomenzo, Lane W. Martin, Simon Martin, Shinji Migita, Thomas Mikolajick, Beatriz Noheda, Min Hyuk Park, Karin M. Rabe, Sayeef Salahuddin, Florencio Sanchez, Konrad Seidel, Takao Shimizu, Takahisa Shiraishi, Stefan Slesazeck, Akira Toriumi, Hiroshi Uchida, Bertrand Vilquin, Xianghan Xu, Kun Hee Ye, Uwe Schroeder
Summary: Ferroelectric hafnium and zirconium oxides have shown significant progress in ultralow-power electronic systems, but technical limitations still hinder their application. This article aims to provide a comprehensive overview of the current state, challenges, and prospects for the development of these materials, with the collaboration of experts from different fields.
Article
Engineering, Electrical & Electronic
Jun Okuno, Tsubasa Yonai, Takafumi Kunihiro, Yusuke Shuto, Ruben Alcala, Maximilian Lederer, Konrad Seidel, Thomas Mikolajick, Uwe Schroeder, Masanori Tsukamoto, Taku Umebayashi
Summary: In this study, we investigated fatigue and recovery phenomenon of hafnium-based one-transistor and one-capacitor (1T1C) ferroelectric random-access memory (FeRAM) using PVD-TiN (30 nm)/ALD- Hf0.5Zr0.5O2 (8 nm)/CVD-TiN (50 nm) capacitors. A single large capacitor was fabricated to understand the recovery mechanism and evaluate the recovery effect. The results revealed that the recovery effect is caused by domain depinning and new domains switching due to oxygen vacancy redistribution. It was also found that the recovery voltage can be reduced by applying a longer recovery pulse width, allowing for more flexible circuit design of 1T1C FeRAM when the recovery method is utilized to enhance cycling endurance.
IEEE JOURNAL OF THE ELECTRON DEVICES SOCIETY
(2023)
Article
Engineering, Electrical & Electronic
Jianran Zhang, Carsten Strobel, Kathrin Estel, Thomas Mikolajick, Robert Kirchner
Summary: Direct writing laser lithography has gained popularity due to its mask-free nature. Among the various techniques, two-photon absorption direct laser writing can create smaller features. However, prolonged immersion can render the photoresist unresponsive, leading to the proposal of using a combination of different immersion liquids and air direct writing for optimal results.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
(2023)
Article
Chemistry, Multidisciplinary
Luis Azevedo Antunes, Richard Ganser, Uwe Schroeder, Thomas Mikolajick, Alfred Kersch
Summary: The phase composition of HZO thin films is crucial for their ferroelectric and electrical properties, but optimizing the phase formation is a challenge due to the complex influencing variables. The Curie temperature is an important parameter that depends on Zr content, oxygen-related defects, layer thickness, and external stress. A two-step process of phase formation involving kinetic transformation and nucleation is proposed. A modified nucleation model with consideration of polycrystalline structure and rescaled interface energies is used to calculate phase fractions and analyze the causes of undesired monoclinic phase.
ADVANCED MATERIALS INTERFACES
(2023)