A5005024198- GaN-based semiconductor devices and materials
- Semiconductor materials and devices
- Ga2O3 and related materials
- Silicon Carbide Semiconductor Technologies
- Semiconductor Quantum Structures and Devices
- Advancements in Semiconductor Devices and Circuit Design
- ZnO doping and properties
- Electronic and Structural Properties of Oxides
- Radio Frequency Integrated Circuit Design
- Thermal properties of materials
- Advanced Photocatalysis Techniques
- Electrostatic Discharge in Electronics
University of Bristol
2018-2024
Stockport College
2021
University of Padua
2014-2017
This paper reports an experimental demonstration of the time-dependent failure GaN-on-Si power high-electron-mobility transistors with p-GaN gate, submitted to a forward gate stress. By means combined dc, optical analysis, and 2-D simulations, we demonstrate following original results: 1) when positive voltage stress (in range 7-9 V), show failure, which leads sudden increase in current; 2) time-to-failure (TTF) is exponentially dependent on Weibull-distributed; 3) TTF depends initial...
This paper reports on the impact of soft- and hard-switching conditions dynamic ON-resistance AlGaN/GaN high-electron mobility transistors. For this study, we used a special double pulse setup, which controls overlapping drain gate waveforms (thus inducing soft hard switching), while measuring corresponding ON-resistance, current, electroluminescence (EL). The results demonstrate that analyzed devices do not suffer from R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...
This paper reports an investigation of the trapping mechanisms responsible for temperature-dependent dynamic-R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> GaN-based metal-insulator-semiconductor (MIS) high electron mobility transistors (HEMTs). More specifically, we perform following. First, propose a novel testing approach, based on combined OFF-state bias, backgating investigation, and positive substrate operation, to separately...
Comparison between pulsed and CW large signal RF performance of field-plated <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> -Ga <sub xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> MOSFETs has been reported. Reduced self-heating when pulse resulted in a power added efficiency 12%, drain 22.4%, output density 0.13...
β-Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> is an attractive material for highvoltage applications and has the potential monolithically integrated RF devices. A combination of Raman nanoparticle thermometry measurement thermal simulation been used to measure peak channel temperature due self-heating in MOSFETs. The resistance measured at gate surface device center was 88 mm ·...
Reverse bias leakage in bulk GaN-on-GaN pn diodes has been studied as a function of time. A peak was observed the current transient and attributed to impurity band conduction along dislocations which is modulated by field effect charged decorating clusters. This model consistent with reports vacancy clustering around during growth.
Although astounding performance is already proven by many research papers, the widespread adoption of GaN power devices in market still hampered (1) yield and reproducibility ; (2) cost (3) reliability. All three factors are to be considered, but convince customers adopt devices, device product reliability a must. Cost kept acceptably low growing epi stack on 6 inch 8inch Si substrates, processing technology standard CMOS production lines. This paper will focus most important intrinsic...
β-Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> thin-channel MOSFETs were evaluated using both dc and pulsed I-V measurements. The reported technique was used to study selfheating effects in the MOSFET channel. device analyzed over a large temperature range of 23 °C-200 °C. A relationship between dissipated power channel established, it found that heating up 208 °C when...
In this article, we investigate the impact of hard-switching on dynamic ON-resistance (RON) in AlGaN/GaN high-electron mobility transistors (HEMTs). The pulsed measurements were taken a set GaN-on-Si wafers, showing significant RON increase after hardswitching compared with soft-switching. was found to be strongly dependent surface passivation stoichiometry. Both hot electrons and self-heating are generated during they investigated separately. For effect, that heating energy dissipated...
The breakdown mechanisms of >1kV <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> -Ga <sub xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> trench-MOS Schottky-barrier (SB) diodes (SBDs) are investigated during step-stressed voltage measurements. We demonstrate the use current leakage noise to characterize...
This paper reports on the trapping mechanism of GaN-based metal-insulator-semiconductor (MIS) high electron mobility transistors (HEMTs) designed to work in a cascode configuration. We defined novel stress protocol (High Temperature, Source Current, HTSC) investigate degradation processes induced by semi-on state operation. compare results HTSC with those obtained standard HTRB (high temperature reverse bias), aim identifying different impact R <sub...
Heat extraction from novel GaN/AlGaN superlattice castellated field effect transistors developed as an RF switch is studied. The device thermal resistance was determined 19.1 ± 0.7 K/(W/mm) a combination of Raman thermography measurements, and gate thermometry. Finite element simulations were used to predict the peak temperatures show that three-dimensional structure aids heat generated in channel. calculated flux castellations shows metal provides high conductivity path, bypassing lower...
This paper describes a laboratory and methodology for the complete assessment of reliability microwave power Gallium Nitride (GaN) devices. Examples related to deep level effects in GaN High Electron Mobility Transistors (HEMTs), HEMT gate degradation time dependent breakdown are described.
This paper presents a detailed study of the failure mechanisms induced by forward bias overstress on gallium nitride (GaN) high electron mobility transistors (HEMTs) with p-type gate. DC measurements demonstrate that GaN-HEMTs p-GaN gate show time-dependent catastrophic degradation when submitted to forward-gate overstress. Time (TTF) can be described Weibull distribution and has an exponential dependence stress voltage. The induces increase in current well correlated electroluminescence...
Abstract In this paper, we investigate the charge trapping in power AlGaN/GaN high electron mobility transistors which occurs ON-state operation ( V DS = 40 V, GS 0 I 0.18 A mm −1 ). By analysing dynamic ON-resistance R ON ) after OFF-state and stress devices with different SiN x passivation stoichiometries, find that can be largely suppressed by a Si concentration passivation. Both potential probe electroluminescence (EL) measurements further confirm induce negative gate–drain access...
The aim of this work is to quantitatively investigate the physical origin temperature-dependent dynamic R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</sub> in GaN based power transistors grown on silicon substrate. analysis combined trapping/detrapping measurements. Trapping was induced by exposing devices two different bias points: off-state (V xmlns:xlink="http://www.w3.org/1999/xlink">GS</sub> =-10 V, V...
We report a novel noise analysis for the leakage current during time-dependent dielectric degradation under bias stress, illustrated using AlGaN/GaN superlattice castellated field-effect transistors (SLCFETs). Gate step stress is standard approach to test robustness of gate in OFF-state conditions. Here, by removing background transients measured parameter analyzer, algorithm gives quantitative value nonstationary superimposed test. Extraction power spectrum windowing and direct fit...
Abstract AlGaN/GaN-based Superlattice Castellated Field Effect Transistors (SLCFET) are the foundation for high power RF amplifiers and switches future radars, although their reliability is not yet well understood. Transistor latching observed in GaN transistors first time. At condition, drain current (ID) transits from an OFF-State value to ON-State sharply with a slope less than 60 mV/decade. Current-voltage (I-V), simulations correlated electroluminescent (EL) emission at condition...
GaN devices are promising candidates for the next generation power energy efficient applications. Although astounding performance is already proven by many research papers, widespread adoption of in market still hampered (1) yield and reproducibility ; (2) cost (3) reliability. All three factors to be considered, but convince customers adopt their products, device product reliability a must. Cost kept acceptably low growing epi stack on 6inch 8inch Si substrates, processing technology...