NFTs (Non-Fungible Tokens) are blockchain-based cryptographic tokens to represent ownership of unique content such as images, videos, or 3D objects. Despite NFTs' increasing popularity and skyrocketing trading prices, little is known about people's perceptions experiences with NFTs. In this work, we focus on NFT creators present results an exploratory qualitative study in which interviewed 15 from nine different countries. Our participants had nuanced feelings their communities. We found...

The degradation behavior and its mechanisms of E-mode GaN high electron mobility transistors (HEMTs) with p-GaN gate under electrostatic discharge (ESD) stress were investigated. Reverse short-pulse was generated by a transmission line pulse (TLP) tester in order to simulate the static electricity. experiment results show that reverse leads characteristic HEMTs gate. values threshold voltage ON-resistance increase, capacitance curve shifts positively. low-frequency noises (LFNs) obtained for...

We have investigated the effect of hot electron stress on electrical properties AlGaN/GaN high mobility transistors (HEMTs) hydrogen poisoning. The HEMTs were biased at semi-on state, and they suffered from stress. devices poisoning degraded, while there is almost no degradation for fresh ones. leads to significantly positive shift threshold voltage notable decrease drain-to-source current For poisoning, trap density increases by about one order magnitude after experiment. physical mechanism...

In this article, we experimentally investigate the degradation mechanisms of GaN high-electron mobility transistors (HEMTs) with p-type gate during long-term hightemperature reverse bias (HTRB) stress and negative temperature instability (NBTI) stress. Based on a number stress/recovery experiments, demonstrate that HTRB could lead to hole emission in p-GaN layer, making threshold voltage (Vth) positively shift, while NBTI result detrapping at AlGaN/GaN interface or AlGaN layer make Vth...

Abstract We propose and analyze a superluminal ring laser gyroscope (RLG) using multilayer optical coatings with huge group delay (GD). This GD assisted RLG can measure the absolute rotation giant sensitivity-enhancement factor of ~10 3 ; while, broadband FWHM enhancement reach 20 MHz. is based on traditional minimal re-engineering beneficial for miniaturization according to theoretical calculation. The idea as fast-light medium will shed lights design application sensors.

The related recovery effect of hydrogen on AlGaN/gallium nitride (GaN) high-electron-mobility transistors (HEMTs) irradiated by high-fluence protons was investigated in this article. results show that under the same temperature and time conditions, induced thermal annealing is better than ordinary annealing. Compared with annealing, proton-irradiated device experienced a 65-mA additional increase saturation current at gate-to-source voltage (V <sub...

In this work, we have comprehensively studied the forward/reverse G-to-S electrostatic discharge (ESD) robustness for Ohmic-gate p-GaN HEMT. It is found that HEMT exhibits superior ESD than Schottky-gate with similar current capacity. First, possesses a high second breakdown ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{\text {SF}}/I_{\text {SR}}$ </tex-math></inline-formula> ) of 9.3/2.7 A, while...

In this paper, we investigated ON-state electroluminescence (EL) characteristics in fresh GaN-based HEMTs under different bias conditions. It demonstrated that: 1) the intensity of EL emitted by with relatively high V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DS</sub> (V > 10 V) monotonically increased as gate voltage increased; and 2) distribution was uniform along across device before stress tests. The degradation process mechanisms...

The ESD effects on the E-mode AlGaN/GaN high-electron mobility transistors (HEMTs) with p-GaN gate are investigated under repetitive TLP pulses. Firstly, degradation and recovery of output, transfer characteristics, gate-leakage characteristics low-frequency noises (LFN) analyzed in detail before after reverse electrostatic discharge (ESD) stress. experimental results show that electrical devices gradually degraded as transmission line pulse (TLP) pules increased. Subsequently, LFN...

In this work, the interaction between hydrogen poisoning (HP) and bias stress in AlGaN/GaN MIS-HEMTs, which incorporate a SiNx gate dielectric, is investigated. The transfer characteristics show that hydrogen-poisoned device exhibits 1.15-V-negative threshold voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> ) shift, significant direct current (DC) ON-resistance (RON_DC) decrease, subthreshold swing (SS) decrease with respect...

In this work, a new method for failure analysis of electronic components, high speed camera, is used to investigate burnout location GaN HEMTs under RF overdrive stress. Based on the camera system and test system, we can filter out most burn flashes, clearly locate weak parts devices. To further explain mechanism, long-term (100 h) stress experiment was carried significant degradation observed. The drain-source current decreases threshold voltage drifts forward. These phenomena show that...

The degradation behavior and its physical mechanism of AlGaN/GaN high electron mobility transistors (HEMTs) during temperature operation (HTO) stress were investigated in this paper. results show that the gate leakage current HEMTs after 1000 h HTO is two orders magnitude larger than fresh ones. maximum transconductance obviously decreases from 0.31 to 0.21 s stress, which indicates degraded seriously. for could be attributed Au diffusion degrades barrier. Moreover, output characteristics...

In this article, the degradation behavior of electrical characteristics AlGaN/GaN HEMTs subjected to radio frequency (RF) overdrive stress has been studied. Trap analysis based on low-frequency noise (LFN) and electroluminescence (EL) characterizations was carried out for before after RF stress. The experimental results show that drain-to-source current is obviously lower than fresh devices. maximum change up 79 mA in saturation zone. threshold voltage drifted forward gate-lag characteristic...

This paper proposes a novel p-GaN HEMT (P-HEMT) by clamping channel potential to improve breakdown voltage (BV) and threshold (VTH) stability. The for P-HEMT is achieved partially-recessed layer (PR layer). At high drain bias, the two-dimensional electron gas (2DEG) under PR depleted withstand bias. Therefore, at drain-side of clamped BV VTH Compared with conventional (C-HEMT), simulation results show that improved 120%, stability induced bias increased 490% same on-resistance. In addition,...

In this work, we demonstrate the degradation behavior and physical mechanism of AlGaN/GaN high-electron-mobility transistors (HEMTs) under hot-electron stress in hydrogen nitrogen atmosphere. According to monitoring results, trends I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ds</sub> values are completely different during same two types The devices pure (the purity is 99.999%) continue decreasing at first then remain a fixed value, whereas...

Despite the superior working properties, GaN-based HEMTs and systems are still confronted with threat of a transient ESD event, especially for vulnerable gate structure p-GaN or MOS HEMTs. Therefore, there is an urgent need bidirectional protection diode to improve robustness GaN power system. In this study, AlGaN/GaN clamp capability was proposed investigated. Through combination two floating electrodes pF-grade capacitors connected in parallel between anode cathode adjacent (CGA (CGC)),...

We have submitted the AlGaN/GaN High electron mobility transistors (HEMTs) to high temperature reverse bias(HTRB) stress assess their reliability for voltage operations. The effects of HTRB as a function V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DG</inf> and time on DC parameters trapping were investigated. study was based combined pulsed characterization, transient measurement. It provides following information: 1) exposure may result...

In this paper, we investigate the degradation mode and mechanism of AlGaN/GaN based high electron mobility transistors (HEMTs) during temperature operation (HTO) stress. It demonstrates that there was abrupt drain current HTO The is ascribed to formation crack under gate which result brittle fracture epilayer on failure analysis. origin mechanical damage further investigated discussed top-down scanning microscope, cross section transmission microscope energy dispersive x-ray spectroscopy...

AlGaN/GaN HEMTs are performed to the HTRB stress experiments investigate degradation phenomena. Several characteristics of DC parameters such as reduction saturated drain current, increase gate leakage current and on-resistance, shift threshold voltage identified. The mechanism is ascribed trapping electrons in region under access drain. speed bottom fingers faster than upside fingers, which meant improvement thermal design important for reliability enhancement HEMTs.

In this paper, thermoreflectance microscopy was used to measure the high spatial resolution temperature distribution of p-GaN HEMT under power density. The maximum along GaN channel located at drain-side gate edge region. It found that thermal resistance (Rth) device increased with increase temperature. Rth dependence on well approximated by a function Rth~Ta (a = 0.2). three phonon Umklapp scattering, point mass defects and dislocations scattering mechanisms are suggested contributors heat...

This work investigated the effects of single stress and electro-thermo-mechanical coupling on electrical properties top-cooled enhancement mode (E-mode) Aluminium Gallium Nitride/Gallium Nitride (AlGaN/GaN) high electron mobility transistor (HEMT) (GS66508T). Planar pressure, linear deformation, punctate environmental temperature, electro-thermal coupling, thermo-mechanical stresses were applied to device. It was found that different kinds had influence mechanisms Namely, excessive...

Abstract During no or minimal avalanche capability, the surge ruggedness of E-mode AlGaN/GaN high-electron mobility transistors (HEMTs) with p-GaN gate has not been fully understood. This work unveils comprehensive results from repetitive unclamped inductive switching (UIS) measurements on commercial p-gate GaN HEMTs. The Electrical parameters degradation and recovery characteristics have investigated. Firstly, a careful study made about output, transfer, leakage, capacitance HEMT devices...

In this work, a novel GaN electrostatic discharge (ESD) protection clamp is proposed for enhancing the gate structure’s ESD reliability of conventional (Con.) p-GaN high-electron-mobility transistor (HEMT). The features floating structure and pF-grade capacitor, which in parallel connection between anode electrode ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${C}_{\text {GA}}$...

A new method is presented to construct grid multi-wing butterfly chaotic attractors. Based on the three-dimensional Lorenz system, two first-order differential equations are added along with one linear coupling controller, respectively. And a piecewise function, which taken into designed form nonlinear controller; thus five-dimensional system produced, able generate gird Through analysis of equilibrium points, Lyapunov exponent spectrums, bifurcation diagrams, and Poincaré mapping in this...