为解决传统功率放大器在管壳外部进行谐波匹配,导致谐波短路传输相位不一致和谐波、基波匹配电路互相影响的问题,基于0.25μm GaN HEMT工艺,对C波段高效率预匹配功率放大器进行研究。功率放大器管壳内部HEMT输入端采用键合线和瓷片电容...为解决传统功率放大器在管壳外部进行谐波匹配,导致谐波短路传输相位不一致和谐波、基波匹配电路互相影响的问题,基于0.25μm GaN HEMT工艺,对C波段高效率预匹配功率放大器进行研究。功率放大器管壳内部HEMT输入端采用键合线和瓷片电容形成T型匹配网络来提升输入阻抗,以HEMT输出端键合线和瓷片电容分别作为电感和电容进行串联,使HEMT输出端对二次谐波短路,控制器件的电压和电流波形,提高放大器的漏极效率。管壳外部利用微带线进行阻抗变换,将输入输出阻抗匹配到50Ω。经测试,GaN HEMT功率放大器在5.8 GHz下饱和输出功率、漏极效率和功率增益分别为48.7 dBm、72%和11.3 dB。展开更多
为了提高半导体器件小信号建模精度并解决优化算法易陷入局部最优解的问题,提出了一种基于改进斑马优化算法(Improved Zebra Optimization Algorithm,IZOA)的氮化镓高电子迁移率晶体管(Gallium Nitride High Electron Mobility Transist...为了提高半导体器件小信号建模精度并解决优化算法易陷入局部最优解的问题,提出了一种基于改进斑马优化算法(Improved Zebra Optimization Algorithm,IZOA)的氮化镓高电子迁移率晶体管(Gallium Nitride High Electron Mobility Transistor,GaN HEMT)混合小信号建模方法。采用数学修正法和直接提取法提取小信号参数,建立初步模型,再使用改进的斑马优化算法进一步提高建模的精度。对斑马优化算法(Zebra Optimization Algorithm,ZOA)的改进主要集中在三个方面:采用混沌映射提高初始种群多样性;使用反向学习策略扩大搜索范围;使用动态概率值替代固定值平衡搜索与收敛能力。实验结果表明,IZOA将直接提取法的平均误差从3.47%降至0.19%,相比灰狼优化(Grey Wolf Optimizer,GWO)算法(平均误差0.95%)降低0.76%,较标准ZOA(平均误差0.52%)降低0.33%,验证了算法的有效性和准确性。展开更多
随着5G通信、毫米波雷达和卫星通信系统对高频大功率器件线性度要求的不断提升,传统AlGaN/GaN高电子迁移率晶体管(High Electron Mobility Transfer,HEMT)在功率放大器应用中面临的非线性失真问题日益凸显。本文针对高线性度氮化镓功率...随着5G通信、毫米波雷达和卫星通信系统对高频大功率器件线性度要求的不断提升,传统AlGaN/GaN高电子迁移率晶体管(High Electron Mobility Transfer,HEMT)在功率放大器应用中面临的非线性失真问题日益凸显。本文针对高线性度氮化镓功率放大器件的设计需求,基于Silvaco TCAD软件,系统研究了栅源/栅漏间距(Lgs/Lgd)、异质结势垒层Al组分分布以及栅下凹槽结构对GaN HEMT器件转移特性及线性度关键指标--栅压摆幅(Gate Voltage Swing,GVS)的影响规律。通过对比分析发现,减小栅源栅漏间距以及增大栅源栅漏Al组分能够有效提高器件的GVS。减小栅下Al组分可以改善器件GVS大小并使器件的阈值电压正漂,随后结合栅下凹槽使得器件的GVS提高了55.56%。本研究为高线性度GaN功率器件的结构优化提供了系统的设计方法和理论依据。展开更多
Gallium nitride(GaN)-based devices have significant potential for space applications.However,the mechanisms of radiation damage to the device,particularly from strong ionizing radiation,remains unknown.This study inve...Gallium nitride(GaN)-based devices have significant potential for space applications.However,the mechanisms of radiation damage to the device,particularly from strong ionizing radiation,remains unknown.This study investigates the effects of radiation on p-gate AlGaN/GaN high-electron-mobility transistors(HEMTs).Under a high voltage,the HEMT leakage current increased sharply and was accompanied by a rapid increase in power density that caused"thermal burnout"of the devices.In addition,a burnout signature appeared on the surface of the burned devices,proving that a single-event burnout effect occurred.Additionally,degradation,including an increase in the on-resistance and a decrease in the breakdown voltage,was observed in devices irradiated with high-energy heavy ions and without bias.The latent tracks induced by heavy ions penetrated the heterojunction interface and extended into the GaN layer.Moreover,a new type of N_(2)bubble defect was discovered inside the tracks using Fresnel analysis.The accumulation of N_(2)bubbles in the heterojunction and buffer layers is more likely to cause leakage and failure.This study indicates that electrical stress accelerates the failure rate and that improving heat dissipation is an effective reinforcement method for GaN-based devices.展开更多
In this work,we investigate the impact of the whole small recess offset on DC and RF characteristics of InP high electron mobility transistors(HEMTs).L_(g)=80 nm HEMTs are fabricated with a double-recessed gate proces...In this work,we investigate the impact of the whole small recess offset on DC and RF characteristics of InP high electron mobility transistors(HEMTs).L_(g)=80 nm HEMTs are fabricated with a double-recessed gate process.We focus on their DC and RF responses,including the maximum transconductance(g_(m_max)),ON-resistance(R_(ON)),current-gain cutoff frequency(f_(T)),and maximum oscillation frequency(f_(max)).The devices have almost same RON.The g_(m_max) improves as the whole small recess moves toward the source.However,a small gate to source capacitance(C_(gs))and a small drain output conductance(g_(ds))lead to the largest f_(T),although the whole small gate recess moves toward the drain leads to the smaller g_(m_max).According to the small-signal modeling,the device with the whole small recess toward drain exhibits an excellent RF characteristics,such as f_(T)=372 GHz and f_(max)=394 GHz.This result is achieved by paying attention to adjust resistive and capacitive parasitics,which play a key role in high-frequency response.展开更多
In the present work,the high uniform 6-inch single-crystalline AlN template is successfully achieved by high temperature annealing technique,which opens up the path towards industrial application in power device.Moreo...In the present work,the high uniform 6-inch single-crystalline AlN template is successfully achieved by high temperature annealing technique,which opens up the path towards industrial application in power device.Moreover,the outstanding crystalline-quality is confirmed by Rutherford backscattering spectrometry(RBS).In accompanied with the results from X-ray diffraction,the RBS results along both[0001]and[1213]reveal that the in-plane lattice is effectively reordered by high temperature annealing.In addition,the constantΦ_(epi)angle between[0001]and[1213]at different depths of 31.54°confirms the uniform compressive strain inside the AlN region.Benefitting from the excellent crystalline quality of AlN template,we can epitaxially grow the enhanced-mode high electron mobility transistor(HEMT)with a graded AlGaN buffer as thin as only~300 nm.Such an ultra-thin AlGaN buffer layer results in the wafer-bow as low as 18.1μm in 6-inch wafer scale.The fabricated HEMT devices with 16μm-L_(GD)exhibits a threshold voltage(V_(TH))of 1.1 V and a high OFF-state breakdown voltage(V_(BD))over 1400 V.Furthermore,after 200 V high-voltage OFF-state stress,the current collapse is only 13.6%.Therefore,the advantages of both 6-inch size and excellent crystallinity announces the superiority of single-crystalline AlN template in low-cost electrical power applications.展开更多
文摘为了提高半导体器件小信号建模精度并解决优化算法易陷入局部最优解的问题,提出了一种基于改进斑马优化算法(Improved Zebra Optimization Algorithm,IZOA)的氮化镓高电子迁移率晶体管(Gallium Nitride High Electron Mobility Transistor,GaN HEMT)混合小信号建模方法。采用数学修正法和直接提取法提取小信号参数,建立初步模型,再使用改进的斑马优化算法进一步提高建模的精度。对斑马优化算法(Zebra Optimization Algorithm,ZOA)的改进主要集中在三个方面:采用混沌映射提高初始种群多样性;使用反向学习策略扩大搜索范围;使用动态概率值替代固定值平衡搜索与收敛能力。实验结果表明,IZOA将直接提取法的平均误差从3.47%降至0.19%,相比灰狼优化(Grey Wolf Optimizer,GWO)算法(平均误差0.95%)降低0.76%,较标准ZOA(平均误差0.52%)降低0.33%,验证了算法的有效性和准确性。
文摘随着5G通信、毫米波雷达和卫星通信系统对高频大功率器件线性度要求的不断提升,传统AlGaN/GaN高电子迁移率晶体管(High Electron Mobility Transfer,HEMT)在功率放大器应用中面临的非线性失真问题日益凸显。本文针对高线性度氮化镓功率放大器件的设计需求,基于Silvaco TCAD软件,系统研究了栅源/栅漏间距(Lgs/Lgd)、异质结势垒层Al组分分布以及栅下凹槽结构对GaN HEMT器件转移特性及线性度关键指标--栅压摆幅(Gate Voltage Swing,GVS)的影响规律。通过对比分析发现,减小栅源栅漏间距以及增大栅源栅漏Al组分能够有效提高器件的GVS。减小栅下Al组分可以改善器件GVS大小并使器件的阈值电压正漂,随后结合栅下凹槽使得器件的GVS提高了55.56%。本研究为高线性度GaN功率器件的结构优化提供了系统的设计方法和理论依据。
基金supported by the National Natural Science Foundation of China(Nos.12035019,62234013,12205350,12075290,12175287)the China National Postdoctoral Program for Innovative Talents(BX20200340)+1 种基金the fund of Innovation Center of Radiation Application(No.KFZC2022020601)the Chinese Academy of Sciences(CAS)“Light of West China"Program hosted by Jian Zeng.
文摘Gallium nitride(GaN)-based devices have significant potential for space applications.However,the mechanisms of radiation damage to the device,particularly from strong ionizing radiation,remains unknown.This study investigates the effects of radiation on p-gate AlGaN/GaN high-electron-mobility transistors(HEMTs).Under a high voltage,the HEMT leakage current increased sharply and was accompanied by a rapid increase in power density that caused"thermal burnout"of the devices.In addition,a burnout signature appeared on the surface of the burned devices,proving that a single-event burnout effect occurred.Additionally,degradation,including an increase in the on-resistance and a decrease in the breakdown voltage,was observed in devices irradiated with high-energy heavy ions and without bias.The latent tracks induced by heavy ions penetrated the heterojunction interface and extended into the GaN layer.Moreover,a new type of N_(2)bubble defect was discovered inside the tracks using Fresnel analysis.The accumulation of N_(2)bubbles in the heterojunction and buffer layers is more likely to cause leakage and failure.This study indicates that electrical stress accelerates the failure rate and that improving heat dissipation is an effective reinforcement method for GaN-based devices.
基金Supported by the Terahertz Multi User RF Transceiver System Development Project(Z211100004421012).
文摘In this work,we investigate the impact of the whole small recess offset on DC and RF characteristics of InP high electron mobility transistors(HEMTs).L_(g)=80 nm HEMTs are fabricated with a double-recessed gate process.We focus on their DC and RF responses,including the maximum transconductance(g_(m_max)),ON-resistance(R_(ON)),current-gain cutoff frequency(f_(T)),and maximum oscillation frequency(f_(max)).The devices have almost same RON.The g_(m_max) improves as the whole small recess moves toward the source.However,a small gate to source capacitance(C_(gs))and a small drain output conductance(g_(ds))lead to the largest f_(T),although the whole small gate recess moves toward the drain leads to the smaller g_(m_max).According to the small-signal modeling,the device with the whole small recess toward drain exhibits an excellent RF characteristics,such as f_(T)=372 GHz and f_(max)=394 GHz.This result is achieved by paying attention to adjust resistive and capacitive parasitics,which play a key role in high-frequency response.
基金supported by the National Key R&D Program of China(No.2022YFE0140100)the National Natural Science Foundation of China(Nos.52273271 and 62321004)partly supported by the Key R&D Program of Guangdong Province(No.2020B01074003)。
文摘In the present work,the high uniform 6-inch single-crystalline AlN template is successfully achieved by high temperature annealing technique,which opens up the path towards industrial application in power device.Moreover,the outstanding crystalline-quality is confirmed by Rutherford backscattering spectrometry(RBS).In accompanied with the results from X-ray diffraction,the RBS results along both[0001]and[1213]reveal that the in-plane lattice is effectively reordered by high temperature annealing.In addition,the constantΦ_(epi)angle between[0001]and[1213]at different depths of 31.54°confirms the uniform compressive strain inside the AlN region.Benefitting from the excellent crystalline quality of AlN template,we can epitaxially grow the enhanced-mode high electron mobility transistor(HEMT)with a graded AlGaN buffer as thin as only~300 nm.Such an ultra-thin AlGaN buffer layer results in the wafer-bow as low as 18.1μm in 6-inch wafer scale.The fabricated HEMT devices with 16μm-L_(GD)exhibits a threshold voltage(V_(TH))of 1.1 V and a high OFF-state breakdown voltage(V_(BD))over 1400 V.Furthermore,after 200 V high-voltage OFF-state stress,the current collapse is only 13.6%.Therefore,the advantages of both 6-inch size and excellent crystallinity announces the superiority of single-crystalline AlN template in low-cost electrical power applications.
