Article
Automation & Control Systems
Pawel Gorecki, Daniel Wojciechowski
Summary: This article presents a novel and improved method for computing the IGBT junction temperature in PLECS simulation software. The method aims to improve accuracy by using a more sophisticated model of transistor losses and accounting for the variability of transistor thermal resistance with temperature. The proposed method is experimentally verified for a dc-dc boost converter, and any discrepancies between simulations and measurements are discussed. It is well-suited for accurate electrothermal circuit-level simulations of power electronics converters.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Physics, Applied
Nachiket R. Naik, Austin J. Minnich
Summary: Silicon-germanium heterojunction bipolar transistors (HBTs) are considered as low-noise microwave amplifiers due to their competitive noise performance and cost effectiveness. Previous studies suggested that quasiballistic electron transport across the base may lead to non-ideal IV characteristics at cryogenic temperatures, but this conclusion has not been thoroughly tested against theoretical predictions. This research used an exact, semi-analytic solution of the Boltzmann equation to study non-diffusive transport in narrow-base SiGe HBTs and found that the computed transport characteristics do not align with experimental results, indicating that quasiballistic electron transport is unlikely to be the cause of cryogenic non-ideal IV characteristics.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Yiao Li, Guofu Niu, Wei Chen
Summary: This article presents the measurement and compact modeling of recovery transients in SiGe heterojunction bipolar transistors. By improving the external base-collector diffusion charge model, accurate modeling of the recovery process is achieved.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
K. Nidhin, Suresh Balanethiram, Deleep R. R. Nair, Rosario D'Esposito, Nihar R. R. Mohapatra, Sebastien Fregonese, Thomas Zimmer, Anjan Chakravorty
Summary: This article presents a robust technique to extract the thermal resistance component originating from the BEOL metal layers in SiGe HBTs. The proposed technique is validated using analytical equations, 3-D TCAD simulations, and measured data from fabricated SiGe HBT structures. The results demonstrate the accuracy and consistency of the extracted parameters across different emitter dimensions and BEOL configurations.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Xiaodi Jin, Guangsheng Liang, Markus Mueller, Michael Schroeter
Summary: The thermal resistance R-th of SiGe heterojunction bipolar transistors (HBTs) has been characterized and modeled from cryogenic temperatures up to room temperature (RT). An analytical solution based on physics has been derived for this wide temperature range. Two formulations, considering both chuck temperature and power dependence of R-th, have been developed and show good agreement with data from both 3-D thermal simulation and measurements.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Electrical & Electronic
Jaewan Lim, Jinsu Jeong, Junjong Lee, Seunghwan Lee, Sanguk Lee, Yonghwan Ahn, Rock-Hyun Baek
Summary: In this study, the self-heating effect of sub-3-nm node forksheet (FS) field-effect transistors (FETs) and nanosheet (NS) FETs was analyzed using a fully calibrated technology computer-aided design simulation. The results showed that FSFETs had superior electrothermal characteristics compared to NSFETs at the single device level and in ring oscillators. Owing to lower maximum lattice temperature variations, FSFETs were less impacted by the self-heating effect-induced degradation.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Computer Science, Information Systems
Zhuoqi Li, Shuhuan Liu, Ci Song, Ning Han, Mathew Adefusika Adekoya
Summary: The degradation characteristics of SiGe HBTs under different bias modes after irradiation were studied, showing varying levels of degradation under different bias conditions.
Article
Nuclear Science & Technology
Jincan Zhang, Haiyi Cai, Na Li, Liwen Zhang, Min Liu, Shi Yang
Summary: A novel model that takes into account the gamma radiation effects is proposed in this paper to predict the lifetime of InP Heterojunction Bipolar Transistor (HBT) devices and related circuits in the space radiation environment. By analyzing the radiation-induced device degradation effects, including both DC and AC characteristics, a set of empirical expressions describing the device degradation trend are presented and incorporated into the Keysight model. A series of radiation experiments were performed to validate the effectiveness of the proposed model, and the correctness of the novel model is confirmed by comparing experimental and simulated results before and after radiation.
NUCLEAR ENGINEERING AND TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Oliver Dieball, Holger Ruecker, Bernd Heinemann, Christoph Jungemann
Summary: This study reveals that the underestimation of the peak cutoff frequency of high-speed silicon-germanium heterojunction bipolar transistors is not due to a breakdown of the HD approximation. The impact of external uniaxial stress on the cutoff frequency is not significant, and in some cases, it can even decrease the frequency.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Review
Engineering, Electrical & Electronic
Markus Mueller, Vincenzo D'Alessandro, Sophia Falk, Christoph Weimer, Xiaodi Jin, Mario Krattenmacher, Pascal Kuthe, Martin Claus, Michael Schroeter
Summary: This review evaluates and discusses several widely used methods for extracting the thermal resistance of heterojunction bipolar transistors (HBTs), including the underlying assumptions, suitable operating point range, and necessary measurement effort. The accuracy of each method is determined by applying it to data based on circuit simulations and experimental data from advanced SiGe and III-V HBT technologies. A guideline for selecting the most suitable method in practice is also provided.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Engineering, Electrical & Electronic
Nelson E. Sepulveda-Ramos, Jeffrey W. Teng, Adrian Ildefonso, Harrison P. Lee, Sunil G. Rao, John D. Cressler
Summary: This research investigates the impact of transistor layout on the RF and thermal performance of 90-nm SiGe heterojunction bipolar transistors. The study shows that there is only slight degradation in small-signal RF figures-of-merit, while large-signal RF figures-of-merit relevant to power amplifiers (PAs) are improved. The optimal device layout variations can help circuit designers mitigate thermal memory effects at the device level, thus improving the overall large-signal linearity of PAs.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Electrical & Electronic
Salvatore Race, Aron Philipp, Michel Nagel, Thomas Ziemann, Ivana Kovacevic-Badstuebner, Ulrike Grossner
Summary: This article proposes a new step-back-correction technique to reduce computational cost for electrothermal simulations of multichip power modules, while considering the importance of thermal conductivity. The proposed method was validated through COMSOL simulations and infrared camera measurements.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Soumya Ranjan Panda, Thomas Zimmer, Anjan Chakravorty, Nicolas Derrier, Sebastien Fregonese
Summary: This study delves into the high-frequency behavior of state-of-the-art SiGe HBTs and presents a comprehensive methodology for extracting HF parameters. The results of this study are of great significance for improving the accuracy of models.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Physics, Applied
Chenlu Wang, Hong Zhou, Jincheng Zhang, Wenxiang Mu, Jie Wei, Zhitai Jia, Xuefeng Zheng, Xiaorong Luo, Xutang Tao, Yue Hao
Summary: In this study, high performance hysteresis-free and ps-switching depletion/enhancement-mode beta-Ga2O3 heterojunction field effect transistors (FETs) with state-of-the-art power figure-of-merit (P-FOM) were successfully established. The positive threshold voltage and low subthreshold slope were achieved by optimizing the p-NiOx/n-Ga2O3 interface and n-Ga2O3 recess technology. Incorporation of T-shaped NiOx improved the trade-off between on-resistance and breakdown voltage, resulting in the highest reported P-FOM among lateral Ga2O3 FETs. The high-quality interface allowed for negligible hysteresis and ps-switching, demonstrating the great potential of Ga2O3 HJ-FETs in high-power, high-efficiency, and high-speed power electronics.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Chao Yang, Tao Peng, Xiaolin Huang, Xinyu Fan, Hongwei Tao, Chunhua Yang, Weihua Gui
Summary: This paper proposes an electrothermal performance-based FCS-MPC (ETP-FCS-MPC) for dynamic thermal balance control in modular multilevel converters. The method achieves thermal stress balance in a more intuitive and time-saving way, and provides dynamic compromise schemes between electrical and thermal performance during speed switching.
IEEE TRANSACTIONS ON TRANSPORTATION ELECTRIFICATION
(2022)
Article
Engineering, Electrical & Electronic
Alberto Maria Angelotti, Gian Piero Gibiino, Troels S. Nielsen, Dominique Schreurs, Alberto Santarelli
Summary: This study investigates wideband active loadpull using a standard VNA with calibrated frequency-domain relative measurements, without the need for time-domain waveforms, enabling processing of large bandwidth modulated signals. Linear precompensation methods are shown to significantly improve the speed and stability of the algorithm.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2021)
Article
Computer Science, Information Systems
Mattia Mengozzi, Gian Piero Gibiino, Alberto M. Angelotti, Corrado Florian, Alberto Santarelli
Summary: This work introduces a predistorter learning procedure based on a multi-objective optimization approach, aiming to maximize RF output power while ensuring a prescribed linearity level. Experimental results demonstrate the effectiveness of this approach over the classical indirect learning architecture.
Article
Engineering, Multidisciplinary
Gian Piero Gibiino, Alberto Santarelli, Pier Andrea Traverso
Summary: This paper presents an on-wafer measurement architecture for the broadband pulsed characterization of RF power FETs, showcasing its flexibility in evaluating FET performance degradation and demonstrating different measurement techniques in the kHz-to-GHz range. The set-up allows synthesis and measurement of pulsed waveforms with short pulse rise/fall times and is particularly suited for assessing low-frequency dispersive effects.
Article
Engineering, Electrical & Electronic
Mattia Mengozzi, Alberto Maria Angelotti, Gian Piero Gibiino, Corrado Florian, Alberto Santarelli
Summary: A generalized dual-input digital predistortion methodology is proposed for supply-modulated power amplifiers, combining SM and RF signals for joint predistortion. A multi-objective optimization strategy is used to optimize DPD coefficients for improved PAE and higher RF output power. Fast simulation of an empirical surrogate model is implemented to make MOO feasible, allowing for dynamic supply shaping and automatic consideration of signals' statistics.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2022)
Article
Engineering, Multidisciplinary
Gian Piero Gibiino, Alberto M. Angelotti, Alberto Santarelli, Pier Andrea Traverso
Summary: The study investigates the combination of EVM measurement method and wideband active load-pull technique for performance evaluation of mismatched power amplifiers across wide modulation bandwidths. A system-level analysis is developed to characterize specific operating regimes under wideband load mismatch. The experimental results show the effectiveness of combining EVM measurement with load-pull techniques for improved wideband RF PA design and characterization.
Article
Energy & Fuels
Mattia Mengozzi, Gian Piero Gibiino, Alberto Maria Angelotti, Alberto Santarelli, Corrado Florian, Paolo Colantonio
Summary: Digitally controlled Dual-Input Doherty Power Amplifiers (DIDPAs) are popular for their flexible input signal splitting, but parameter setting is challenging. This article presents automated parameter setting based on coordinate descent and Bayesian optimizations, improving amplifier performance for broadband-modulated signals and communication applications.
Article
Computer Science, Information Systems
Alessio Alemanno, Alberto Santarelli, Enrico Sangiorgi, Corrado Florian
Summary: The paper discusses the advantages of high-voltage GaN switches over silicon counterparts and the issues related to charge-trapping effects. A technique based on a half bridge switching leg design is proposed to characterize the dynamic ON-resistance of high-voltage GaN switches under real operating conditions.
Article
Computer Science, Information Systems
Alessio Alemanno, Alberto Maria Angelotti, Gian Piero Gibiino, Alberto Santarelli, Enrico Sangiorgi, Corrado Florian
Summary: Charge-trapping mechanisms in high-voltage GaN switches lead to degradation of power converter efficiency by modulating the effective dynamic ON-resistance (R-ON) compared to its static value. The degradation is dependent on blocking voltage, commutation frequency, and is particularly significant in new technologies. Characterizing this phenomenon on-wafer under controlled operating conditions is valuable for technology development or quality verification.
Article
Engineering, Electrical & Electronic
Mattia Mengozzi, Gian Piero Gibiino, Alberto M. Angelotti, Corrado Florian, Alberto Santarelli
Summary: An approach based on machine learning is proposed for the global linearization of microwave active beamforming arrays. The approach allows for real-time update of the digital predistortion (DPD) coefficients using order-reduced model features, eliminating the need for repeated local DPD identification steps under different operating conditions. The validation was conducted through OTA measurements of a 1 x 4 array operating at 28 GHz across 100-MHz modulation bandwidth (BW).
IEEE MICROWAVE AND WIRELESS TECHNOLOGY LETTERS
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Alberto Maria Angelotti, Gian Piero Gibiino, Troels S. Nielsent, Alberto Santarelli, Jan Verspechtt
Summary: This work examines the impact of broadband modulated excitations on the load-pull characterization of GaN transistors and compares different measurement approaches under realistic conditions.
2022 99TH ARFTG MICROWAVE MEASUREMENT CONFERENCE (ARFTG): FROM FUNDAMENTAL TO CUTTING-EDGE MICROWAVE MEASUREMENT TECHNIQUES TO SUPPORT 6G AND BEYOND
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Mattia Mengozzi, Gian Piero Gibiino, Alberto M. Angelotti, Corrado Florian, Alberto Santarelli
Summary: A method for assessing the complexity of beamformer arrays in the context of digital predistortion (DPD) is proposed, which demonstrates the compensation of the linear response of the transmitter and enhances the linearization performance. It also allows for analyzing the residual distortion when using a unique set of DPD coefficients across different beam angles and receiver positions.
2022 IEEE/MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM (IMS 2022)
(2022)
Article
Engineering, Electrical & Electronic
Alberto Maria Angelotti, Gian Piero Gibiino, Alberto Santarelli, Pier Andrea Traverso
Summary: This study proposes a frequency-domain method to measure the broadband error vector magnitude (EVM) for vector signal generators (VSGs). The method utilizes a stable reference signal and a vector network analyzer for frequency-swept narrowband acquisitions. By separating the IQ imbalance effect from the actual distortion, accurate broadband EVM measurements are achieved.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Alberto M. Angelotti, Gian Piero Gibiino, Alberto Santarelli, Troels S. Nielsen, Jan Verspecht
Summary: The proposed method utilizes active modulated signal injection to characterize the amplifier error-vector magnitude (EVM) in the presence of wideband load termination set by the user, based solely on iso-frequency ratioed measurements obtainable with legacy vector network analyzer (VNA) technology. This approach allows for realistic modulation distortion assessment across arbitrarily-wide test bandwidths by removing receiver bandwidth limitations.
97TH ARFTG MICROWAVE MEASUREMENT CONFERENCE: CONDUCTED AND OTA MEASUREMENT CHALLENGES FOR URBAN, RURAL & SATCOMM CONNECTIVITY
(2021)
Article
Engineering, Electrical & Electronic
Corrado Florian, Pier Andrea Traverso, Alberto Santarelli
Summary: A Ka-band monolithic low-noise amplifier (LNA) with high gain and high dynamic range (DR) has been designed and implemented in a 100-nm gallium nitride (GaN)-on-Si technology. The LNA is designed as the first stage of a high DR receiver in an FMCW radar for the detection of small drones. The combination of NF, gain, and DR performance in this frequency band represents the state of art.
IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Gian Piero Gibiino, Alberto Maria Angelotti, Alberto Santarelli, Fabio Filicori, Pier Andrea Traverso
Summary: This study introduces a generalized multitone multiharmonic scattering parameters (MS-S-2-parameters) measurement approach suitable for multiport nonlinear network characterization in the wave-variable domain. It can capture nonlinear steady-state behavior and be effectively used for performance prediction.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
