The upper waveguide （UWG） has direct influences on the optical and electrical characteristics of the violet laser diode （LD） by changing the optical field distribution or barrier of the electron blocking layer （...The upper waveguide （UWG） has direct influences on the optical and electrical characteristics of the violet laser diode （LD） by changing the optical field distribution or barrier of the electron blocking layer （EBL）. In this study, a series of InGaN-based violet LDs with different UWGs are investigated systematically with LASTIP software. It is found that the output light power （OLP） under an injecting current of 120 mA or the threshold current （Ith） is deteriorated when the UWG is u-In0.02Ga0.98N/GaN or u-In0.02Ga0.98N/AlxGa1-xN （0 ≤ x ≤ 0.1）, which should be attributed to small optical confinement factor （OCF） or severe electron leakage. Therefore, a new violet LD structure with u-In0.02Ga0.98N/GaN/Al0.05Ga0.95N multiple layer UWG is proposed to reduce the optical loss and increase the barrier of EBL. Finally, the output light power under an injecting current of 120 mA is improved to 176.4 mW.展开更多
Polarization-induced two-dimensional hole gases(2DHG)in GaN/AlGaN/GaN heterostructures offer a promising pathway for advancing p-channel transistors.This work investigates the impact of p-GaN thickness on hole distrib...Polarization-induced two-dimensional hole gases(2DHG)in GaN/AlGaN/GaN heterostructures offer a promising pathway for advancing p-channel transistors.This work investigates the impact of p-GaN thickness on hole distribution and transport through temperature-dependent Hall measurements and TCAD simulations.It is demonstrated that the p-channel is composed of holes both in the p-GaN layer and in the 2DHG at the GaN/AlGaN heterointerface at 300 K,whereas at 77 K,the p-channel conduction is dominated solely by the 2DHG at the GaN/AlGaN heterointerface.The results also reveal the formation of a polarization-induced 2DHG at the GaN/AlGaN interface,exhibiting a high sheet density of 2.2×10^(13)cm^(-2)and a mobility of 16.2 cm^(2)·V^(-1)·s^(-1)at 300 K.The 2DHG sheet density remains nearly independent of p-GaN thickness when the p-GaN layer exceeds 30 nm.However,for p-GaN layers thinner than 30 nm,the 2DHG sheet density strongly depends on the p-GaN thickness,which is attributed to the gradual extension of the depletion region toward the GaN/AlGaN interface under the influence of surface trap states.展开更多
The novel structure of the AlGaN/GaN high electron mobility transistor(HEMT)with a groove double field-plate is proposed in this paper,which resolves the issue of the current collapse caused by the high electric field...The novel structure of the AlGaN/GaN high electron mobility transistor(HEMT)with a groove double field-plate is proposed in this paper,which resolves the issue of the current collapse caused by the high electric field at the gate edge of conventional AlGaN/GaN HEMT.The current transport mechanism of the novel device and its effectiveness to suppress current collapse are studied.Based on the introduction of the groove dual-field plate,the depletion region of the novel device is extended.The electric field peak at the gate edge is reduced and the distribution of the electric field is more uniform.As a result,the new structure can improve the current collapse without significantly reducing the drain current.Compared with the conventional AlGaN/GaN HEMT,the suppression effect of the new device on the current collapse effect is increased by 94.1%when L_(fp1)=0.3μm and L_(fp2)=0.7μm.展开更多
Research on p-channel field-effect transistors(p-FETs)remains limited,primarily due to the significantly lower conductivity of the two-dimensional hole gas(2DHG)compared to the two-dimensional electron gas(2DEG)in n-c...Research on p-channel field-effect transistors(p-FETs)remains limited,primarily due to the significantly lower conductivity of the two-dimensional hole gas(2DHG)compared to the two-dimensional electron gas(2DEG)in n-channel field-effect transistors(n-FETs),which poses a significant challenge for monolithic integration.In this study,we investigate the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures through semiconductor technology computer-aided design(TCAD)simulations and theoretical calculations,identifying the conditions necessary to achieve high-density 2DHG.Our simulations demonstrate that increasing the p-Ga N thickness leads to two critical thicknesses determined by surface states and acceptor ionization concentration:one corresponds to the onset of 2DHG formation,and the other to its saturation.Lowering the donor surface state energy level and increasing the acceptor ionization concentration promote 2DHG formation and saturation,although the saturated density remains independent of surface states.Additionally,a higher Al composition enhances intrinsic ionization due to stronger polarization effects,thereby increasing the 2DHG sheet density.Consequently,to achieve high-density 2DHG in p-Ga N/Al Ga N/Ga N heterostructures,it is essential to increase the Al composition,ensure that the p-Ga N thickness exceeds the critical thickness for 2DHG saturation,and maximize the acceptor ionization concentration.This study elucidates the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures and provides valuable guidance for the optimization of p-FET designs.展开更多
报道了研制的 Al Ga N / Ga N微波功率 HEMT,该器件采用以蓝宝石为衬底的非掺杂 Al Ga N/ Ga N异质结构 ,器件工艺采用了 Ti/ Al/ Ni/ Au欧姆接触和 Ni/ Au肖特基势垒接触以及 Si N介质进行器件的钝化 .研制的 2 0 0μm栅宽 T型布局 Al ...报道了研制的 Al Ga N / Ga N微波功率 HEMT,该器件采用以蓝宝石为衬底的非掺杂 Al Ga N/ Ga N异质结构 ,器件工艺采用了 Ti/ Al/ Ni/ Au欧姆接触和 Ni/ Au肖特基势垒接触以及 Si N介质进行器件的钝化 .研制的 2 0 0μm栅宽 T型布局 Al Ga N / Ga N HEMT在 1.8GHz,Vds=30 V时输出功率为 2 8.93d Bm,输出功率密度达到 3.9W/mm ,功率增益为 15 .5 9d B,功率附加效率 (PAE)为 4 8.3% .在 6 .2 GHz,Vds=2 5 V时该器件输出功率为 2 7.0 6 d Bm ,输出功率密度为 2 .5 W/ mm ,功率增益为 10 .2 4 d B,PAE为 35 .2 % .展开更多
在考虑 Al Ga N / Ga N异质结中的压电极化和自发极化效应的基础上 ,自洽求解了垂直于沟道方向的薛定谔方程和泊松方程 .通过模拟计算 ,研究了 Al Ga N / Ga N HEMT器件掺杂层 Al的组分、厚度、施主掺杂浓度以及栅偏压对二维电子气特性...在考虑 Al Ga N / Ga N异质结中的压电极化和自发极化效应的基础上 ,自洽求解了垂直于沟道方向的薛定谔方程和泊松方程 .通过模拟计算 ,研究了 Al Ga N / Ga N HEMT器件掺杂层 Al的组分、厚度、施主掺杂浓度以及栅偏压对二维电子气特性的影响 .用准二维物理模型计算了 Al Ga N/ Ga N HEMT器件的输出特性 ,给出了相应的饱和电压和阈值电压 ,并对计算结果和 Al Ga N/ Ga N HEMT器件的结构优化进行了分析 .展开更多
基金Project supported by the National Key R&D Program of China(Grant Nos.2016YFB0400803 and 2016YFB0401801)the National Natural Science Foundation of China(Grant Nos.61674138,61674139,61604145,61574135,61574134,61474142,61474110,61377020,and 61376089)+1 种基金the Science Challenge Project,China(Grant No.TZ2016003)the Beijing Municipal Science and Technology Project,China(Grant No.Z161100002116037)
文摘The upper waveguide （UWG） has direct influences on the optical and electrical characteristics of the violet laser diode （LD） by changing the optical field distribution or barrier of the electron blocking layer （EBL）. In this study, a series of InGaN-based violet LDs with different UWGs are investigated systematically with LASTIP software. It is found that the output light power （OLP） under an injecting current of 120 mA or the threshold current （Ith） is deteriorated when the UWG is u-In0.02Ga0.98N/GaN or u-In0.02Ga0.98N/AlxGa1-xN （0 ≤ x ≤ 0.1）, which should be attributed to small optical confinement factor （OCF） or severe electron leakage. Therefore, a new violet LD structure with u-In0.02Ga0.98N/GaN/Al0.05Ga0.95N multiple layer UWG is proposed to reduce the optical loss and increase the barrier of EBL. Finally, the output light power under an injecting current of 120 mA is improved to 176.4 mW.
基金supported by the National Key Research and Development Program of China(Grant No.2024YFE0205000)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20243037)+2 种基金the National Natural Science Foundation of China(Grant Nos.62074077 and 61921005)the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20231098)the Collab-orative Innovation Center of Solid State Lighting and Energy-Saving Electronics.
文摘Polarization-induced two-dimensional hole gases(2DHG)in GaN/AlGaN/GaN heterostructures offer a promising pathway for advancing p-channel transistors.This work investigates the impact of p-GaN thickness on hole distribution and transport through temperature-dependent Hall measurements and TCAD simulations.It is demonstrated that the p-channel is composed of holes both in the p-GaN layer and in the 2DHG at the GaN/AlGaN heterointerface at 300 K,whereas at 77 K,the p-channel conduction is dominated solely by the 2DHG at the GaN/AlGaN heterointerface.The results also reveal the formation of a polarization-induced 2DHG at the GaN/AlGaN interface,exhibiting a high sheet density of 2.2×10^(13)cm^(-2)and a mobility of 16.2 cm^(2)·V^(-1)·s^(-1)at 300 K.The 2DHG sheet density remains nearly independent of p-GaN thickness when the p-GaN layer exceeds 30 nm.However,for p-GaN layers thinner than 30 nm,the 2DHG sheet density strongly depends on the p-GaN thickness,which is attributed to the gradual extension of the depletion region toward the GaN/AlGaN interface under the influence of surface trap states.
基金supported by the Key Research and Development Program of Shannxi under Grant 2022GY-016the National Natural Science Foundation of China under Grant 52377197.
文摘The novel structure of the AlGaN/GaN high electron mobility transistor(HEMT)with a groove double field-plate is proposed in this paper,which resolves the issue of the current collapse caused by the high electric field at the gate edge of conventional AlGaN/GaN HEMT.The current transport mechanism of the novel device and its effectiveness to suppress current collapse are studied.Based on the introduction of the groove dual-field plate,the depletion region of the novel device is extended.The electric field peak at the gate edge is reduced and the distribution of the electric field is more uniform.As a result,the new structure can improve the current collapse without significantly reducing the drain current.Compared with the conventional AlGaN/GaN HEMT,the suppression effect of the new device on the current collapse effect is increased by 94.1%when L_(fp1)=0.3μm and L_(fp2)=0.7μm.
基金Project supported by the National Key Research and Development Program of China(Grant No.2022YFB3604203)the Key Research and Development Program of Guangdong Province,China(Grant No.2024B0101060002)the Key Research and Development Program of Shenzhen City,China(Grant No.JCYJ20241202130036043)。
文摘Research on p-channel field-effect transistors(p-FETs)remains limited,primarily due to the significantly lower conductivity of the two-dimensional hole gas(2DHG)compared to the two-dimensional electron gas(2DEG)in n-channel field-effect transistors(n-FETs),which poses a significant challenge for monolithic integration.In this study,we investigate the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures through semiconductor technology computer-aided design(TCAD)simulations and theoretical calculations,identifying the conditions necessary to achieve high-density 2DHG.Our simulations demonstrate that increasing the p-Ga N thickness leads to two critical thicknesses determined by surface states and acceptor ionization concentration:one corresponds to the onset of 2DHG formation,and the other to its saturation.Lowering the donor surface state energy level and increasing the acceptor ionization concentration promote 2DHG formation and saturation,although the saturated density remains independent of surface states.Additionally,a higher Al composition enhances intrinsic ionization due to stronger polarization effects,thereby increasing the 2DHG sheet density.Consequently,to achieve high-density 2DHG in p-Ga N/Al Ga N/Ga N heterostructures,it is essential to increase the Al composition,ensure that the p-Ga N thickness exceeds the critical thickness for 2DHG saturation,and maximize the acceptor ionization concentration.This study elucidates the impact of epitaxial structure parameters on 2DHG properties in p-Ga N/Al Ga N/Ga N heterostructures and provides valuable guidance for the optimization of p-FET designs.
文摘报道了研制的 Al Ga N / Ga N微波功率 HEMT,该器件采用以蓝宝石为衬底的非掺杂 Al Ga N/ Ga N异质结构 ,器件工艺采用了 Ti/ Al/ Ni/ Au欧姆接触和 Ni/ Au肖特基势垒接触以及 Si N介质进行器件的钝化 .研制的 2 0 0μm栅宽 T型布局 Al Ga N / Ga N HEMT在 1.8GHz,Vds=30 V时输出功率为 2 8.93d Bm,输出功率密度达到 3.9W/mm ,功率增益为 15 .5 9d B,功率附加效率 (PAE)为 4 8.3% .在 6 .2 GHz,Vds=2 5 V时该器件输出功率为 2 7.0 6 d Bm ,输出功率密度为 2 .5 W/ mm ,功率增益为 10 .2 4 d B,PAE为 35 .2 % .
文摘在考虑 Al Ga N / Ga N异质结中的压电极化和自发极化效应的基础上 ,自洽求解了垂直于沟道方向的薛定谔方程和泊松方程 .通过模拟计算 ,研究了 Al Ga N / Ga N HEMT器件掺杂层 Al的组分、厚度、施主掺杂浓度以及栅偏压对二维电子气特性的影响 .用准二维物理模型计算了 Al Ga N/ Ga N HEMT器件的输出特性 ,给出了相应的饱和电压和阈值电压 ,并对计算结果和 Al Ga N/ Ga N HEMT器件的结构优化进行了分析 .
