修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

22 条数据
?? 中文(中国)
  • A reliable and efficient small-signal parameter extraction method for GaN HEMTs

    摘要: In this paper, a reliable and efficient parameter extraction method for GaN high electron mobility transistor (HEMT) small‐signal models has been proposed. By utilizing parameter scanning method, the initial values of the extrinsic elements are first extracted from the cold pinch‐off and cold unbiased measurement conditions, respectively. An iterative optimization algorithm is employed then to optimize the extrinsic elements. This scanning and iteration combined algorithm based on a direct extraction method of extrinsic elements can reduce the impact of the approximation error, which makes the determined values of the small‐signal parameters more reliable. The extraction flow has been realized in a Matlab program for efficiency. A 16‐element small‐signal equivalent circuit model (SSECM) for GaN HEMTs has been employed, and the new parameter extraction method has been validated by comparing the simulated small‐signal S‐parameters with the measured data from 0.1 GHz to 40 GHz for two different device dimensions.

    关键词: small‐signal modeling,parameter extraction,GaN high electron mobility transistor (HEMT)

    更新于2025-09-23 15:23:52

  • Gate Conduction Mechanisms and Lifetime Modeling of p-Gate AlGaN/GaN High-Electron-Mobility Transistors

    摘要: The gate conduction mechanisms in p-gallium nitride (GaN)/AlGaN/GaN enhancement mode transistors are investigated using temperature-dependent dc gate current measurements. In each of the different gate voltage regions, a physical model is proposed and compared to experiment. At negative gate bias, Poole–Frenkel emission (PFE) occurs within the passivation dielectric from gate to source. At positive gate bias, the p-GaN/AlGaN/GaN “p-i-n” diode is in forward operation mode, and the gate current is limited by hole supply at the Schottky contact. At low gate voltages, the current is governed by thermionic emission with Schottky barrier lowering in dislocation lines. Increasing the gate voltage and temperature results in thermally assisted tunneling (TAT) across the same barrier. An improved gate process reduces the gate current in the positive gate bias region and eliminates the onset of TAT. However, at high positive gate bias, a sharp increase in current is observed originating from PFE at the metal/p-GaN interface. Using the extracted conduction mechanisms for both devices, accurate lifetime models are constructed. The device fabricated with the novel gate process exhibits a maximum gate voltage of 7.2 V at t1% = 10 years.

    关键词: time-dependent breakdown (TDB),p-GaN gate,high-electron-mobility transistor (HEMT),enhancement mode,gallium nitride (GaN),Conduction mechanism

    更新于2025-09-23 15:21:21

  • Analysis and design of a multi-channel constant current LED driver based on DC current bus distributed power system structure

    摘要: In this paper, we have extensively investigated the impact of anode recess on the reverse leakage current, forward voltage (VF), and dynamic characteristics of Au-free AlGaN/GaN Schottky barrier diodes with a gated edge termination (GET-SBDs) on 200-mm silicon substrates. By increasing the number of atomic layer etching (ALE) cycles for anode recessing, we have found that: 1) the reverse leakage current is strongly suppressed due to a better electrostatic control for pinching off the channel in the GET region; a median leakage current of ~1 nA/mm and an ION/IOFF ratio higher than 108 have been achieved in GET-SBDs with six ALE cycles; 2) the forward voltage (~1.3 V) is almost independent of the ALE cycles, taking into account its statistical distribution across the wafers; 3) when the remaining AlGaN barrier starts to be very thin (in the case of six ALE cycles), a spread of the ON-resistance, mainly attributed to the GET region, can occur due to the dif?cult control of the remaining AlGaN thickness and surface quality; and 4) the dynamic forward voltage of GET-SBDs shows a mild dependence on the ALE process in pulsed I–V characterization, and a more ALE-dependent dynamic ON-resistance is observed.

    关键词: atomic layer etching (ALE),200-mm,leakage,metal–insulator–semiconductor high-electron mobility transistor (MISHEMT),GET-SBD,diode,AlGaN/GaN

    更新于2025-09-23 15:21:01

  • [IEEE 2019 IEEE International Conference on Mechatronics and Automation (ICMA) - Tianjin, China (2019.8.4-2019.8.7)] 2019 IEEE International Conference on Mechatronics and Automation (ICMA) - Optimization of Spectroscope Parameters for Single-beam Pulsed Laser Scanning Circumferential Detection System

    摘要: In this paper, we have extensively investigated the impact of anode recess on the reverse leakage current, forward voltage (VF), and dynamic characteristics of Au-free AlGaN/GaN Schottky barrier diodes with a gated edge termination (GET-SBDs) on 200-mm silicon substrates. By increasing the number of atomic layer etching (ALE) cycles for anode recessing, we have found that: 1) the reverse leakage current is strongly suppressed due to a better electrostatic control for pinching off the channel in the GET region; a median leakage current of ~1 nA/mm and an ION/IOFF ratio higher than 108 have been achieved in GET-SBDs with six ALE cycles; 2) the forward voltage (~1.3 V) is almost independent of the ALE cycles, taking into account its statistical distribution across the wafers; 3) when the remaining AlGaN barrier starts to be very thin (in the case of six ALE cycles), a spread of the ON-resistance, mainly attributed to the GET region, can occur due to the difficult control of the remaining AlGaN thickness and surface quality; and 4) the dynamic forward voltage of GET-SBDs shows a mild dependence on the ALE process in pulsed I–V characterization, and a more ALE-dependent dynamic ON-resistance is observed.

    关键词: leakage,diode,AlGaN/GaN,GET-SBD,metal–insulator–semiconductor high-electron mobility transistor (MISHEMT),200-mm,atomic layer etching (ALE)

    更新于2025-09-23 15:19:57

  • The origin of distorted intensity pattern sensed by a lens and antenna coupled AlGaN/GaN-HEMT terahertz detectors

    摘要: Here, we report artefacts in the intensity pattern of a focused terahertz beam around 1 THz by scanning photocurrents as a function of the beam location and the frequency. Although the exact distortion is found with our specific antenna design, we believe similar artefacts could be commonplace in antenna-coupled FET terahertz detectors when the beam spot becomes comparable with the antenna size. To eliminate such artefact, new antenna designs are welcomed to achieve strong asymmetry in the terahertz field distribution under the gate while maintaining a more symmetric radiation pattern for the whole antenna.

    关键词: high electron mobility transistor,terahertz detector,self-mixing,local electrical field

    更新于2025-09-23 15:19:57

  • A broadband GaAs pHEMT low noise driving amplifier with current reuse and self-biasing technique

    摘要: A K/Ka-band two-stage low noise driving ampli?er using a 0.15 lm GaAs pHEMT for low noise technology is designed and fabricated. In order to achieve broadband driving capability with low power consumption, current reuse technique is adopted to feed both transistors with the same DC power supply, which theoretically cuts the total current consumption in half. In addition, self-biasing technique is utilized to minimize both external power supply pads and chip footprint, which reduces the number of supply pads to a minimum of two (1 power pad and 1 ground pad). The circuit topology analysis and design procedures are also presented with an emphasis on noise ?gure and P1dB optimization. The low noise driving ampli?er demonstrates a - 3 dB bandwidth of wider than 11 GHz, a power gain of 17 dB, an in-band mean noise ?gure of 2.2 dB and an in-band mean output P1dB of 6 dBm. The DC power consumption is 9.1 mA@3.3 V power supply. The chip size is 1 mm 9 1.5 mm with only 1 external DC feed pad (3.3 V) and 1 ground pad (0 V). With the performance comparable to typical two-stage dual-bias low noise driving ampli?er counterparts, the proposed MMIC is more attractive to chip/system users in volume-limited and power-contrained applications.

    关键词: Ka-band,Pseudomorphic high electron mobility transistor (pHEMT),GaAs,Low noise driving ampli?er,Monolithic microwave integrated circuit (MMIC)

    更新于2025-09-19 17:15:36

  • [IEEE 2019 International Conference on Mechatronics, Robotics and Systems Engineering (MoRSE) - Bali, Indonesia (2019.12.4-2019.12.6)] 2019 International Conference on Mechatronics, Robotics and Systems Engineering (MoRSE) - Bottled Water Identification & Fraud Detection Using Spectroscopy & Convolutional Neural Network

    摘要: In this paper, we have extensively investigated the impact of anode recess on the reverse leakage current, forward voltage (VF), and dynamic characteristics of Au-free AlGaN/GaN Schottky barrier diodes with a gated edge termination (GET-SBDs) on 200-mm silicon substrates. By increasing the number of atomic layer etching (ALE) cycles for anode recessing, we have found that: 1) the reverse leakage current is strongly suppressed due to a better electrostatic control for pinching off the channel in the GET region; a median leakage current of ~1 nA/mm and an ION/IOFF ratio higher than 108 have been achieved in GET-SBDs with six ALE cycles; 2) the forward voltage (~1.3 V) is almost independent of the ALE cycles, taking into account its statistical distribution across the wafers; 3) when the remaining AlGaN barrier starts to be very thin (in the case of six ALE cycles), a spread of the ON-resistance, mainly attributed to the GET region, can occur due to the dif?cult control of the remaining AlGaN thickness and surface quality; and 4) the dynamic forward voltage of GET-SBDs shows a mild dependence on the ALE process in pulsed I–V characterization, and a more ALE-dependent dynamic ON-resistance is observed.

    关键词: atomic layer etching (ALE),200-mm,leakage,metal–insulator–semiconductor high-electron mobility transistor (MISHEMT),GET-SBD,diode,AlGaN/GaN

    更新于2025-09-19 17:13:59

  • Thermal Analysis and Operational Characteristics of an AlGaN/GaN High Electron Mobility Transistor with Copper-Filled Structures: A Simulation Study

    摘要: In this study, we investigated the operational characteristics of AlGaN/GaN high electron mobility transistors (HEMTs) by applying the copper-filled trench and via structures for improved heat dissipation. Therefore, we used a basic T-gate HEMT device to construct the thermal structures. To identify the heat flow across the device structure, a thermal conductivity model and the heat transfer properties corresponding to the GaN, SiC, and Cu materials were applied. Initially, we simulated the direct current (DC) characteristics of a basic GaN on SiC HEMT to confirm the self-heating effect on AlGaN/GaN HEMT. Then, to verify the heat sink effect of the copper-filled thermal structures, we compared the DC characteristics such as the threshold voltage, transconductance, saturation current, and breakdown voltage. Finally, we estimated and compared the lattice temperature of a two-dimensional electron gas channel, the vertical lattice temperature near the drain-side gate head edge, and the transient thermal analysis for the copper-filled thermal trench and via structures. Through this study, we could optimize the operational characteristics of the device by applying an effective heat dissipation structure to the AlGaN/GaN HEMT.

    关键词: thermal conductivity,high electron mobility transistor,GaN,self-heating effect,copper-filled structure

    更新于2025-09-16 10:30:52

  • Thermal Management of GaN-on-Si High Electron Mobility Transistor by Copper Filled Micro-Trench Structure

    摘要: Self-heating effect is a major limitation in achieving the full performance potential of high power GaN power devices. In this work, we reported a micro-trench structure fabricated on the silicon substrate of an AlGaN/GaN high electron mobility transistor (HEMT) via deep reactive ion etching, which was subsequently filled with high thermal conductive material, copper using the electroplating process. From the current-voltage characteristics, the saturation drain current was improved by approximately 17% with the copper filled micro-trench structure due to efficient heat dissipation. The iDS difference between the pulse and DC bias measurement was about 21% at high bias VDS due to the self-heating effect. In contrast, the difference was reduced to approximately 8% for the devices with the implementation of the proposed structure. Using Micro-Raman thermometry, we showed that temperature near the drain edge of the channel can be lowered by approximately ~22 °C in a HEMT operating at ~10.6 Wmm?1 after the implementation of the trench structure. An effective method for the improvement of thermal management to enhance the performance of GaN-on-Silicon HEMTs was demonstrated.

    关键词: thermal management,high electron mobility transistor,self-heating effect,copper filled micro-trench,GaN-on-Si

    更新于2025-09-16 10:30:52

  • Simulation Investigation of Laterally Downscaled N-Polar GaN HEMTs

    摘要: The N-polar GaN high-electron mobility transistors (HEMTs) have demonstrated a powerful performance as the Ga-polar GaN HEMTs. This investigation aims to show the direct current performance and cutoff frequency (fT) of the planar N-polar GaN HEMTs with gate lengths downscaling from 4 μm to 50 nm by 2-D device simulation. The impacts of traps and gate dielectrics and the roles of the ?eld-dependent mobility and the source and drain series resistances are investigated. For our central-gated device with a 10-nm top GaN channel layer, a 30-nm Al0.3Ga0.7N barrier layer, and a 3-nm Al2O3 gate dielectric, the gate length (LG) as the transition point from the long-channel behavior to the short-channel one is found to be 200 nm. For LG < 200 nm, a linear fT versus LG relation shows up, and notable short-channel effects appear, i.e., the negative shift of the threshold voltage, the increase of the drain-induced barrier lowering, and the almost LG-independent constant maximum transconductance in the saturation region. The degradation of the fT × LG product with the decrease in the aspect ratio between LG and the equivalent gate-channel distance (tt) is shown to be quite small. The LG/tt ratio for 15% degradation of the fT × LG product from its upper limit (19.23 GHz · μm) is 5.5. This small degradation of the frequency characteristics in short-channel devices is attributed to the quite small fringing capacitance of the gate.

    关键词: short-channel effect,laterally scaling,N-polar GaN,High-electron mobility transistor (HEMT)

    更新于2025-09-12 10:27:22