The frequency dependent of the forward and reverse bias capacitance-voltage （C-V） and conductance-voltage （G/w-V） charac- teristics of Au/p-InP SBDs have been investigated in the frequency range of 20 kHz-10 MHz a...The frequency dependent of the forward and reverse bias capacitance-voltage （C-V） and conductance-voltage （G/w-V） charac- teristics of Au/p-InP SBDs have been investigated in the frequency range of 20 kHz-10 MHz and voltage range of-5 - 5 V at room temperature. The effects of surface states （Nss） and series resistance （R0 on C-V and G/w-V characteristics have been in- vestigated in detail. The frequency dependent Nss and Rs profiles were obtained for various applied bias voltages. The experi- mental results show that the main electrical parameters of Au/p-InP SBD such as barrier height （gOB）, the density of acceptor concentration （NA）, Nss and Rs were found strongly frequency and voltage dependent. The values of C and G/w decrease with increasing frequency due to a continuous distribution of Nss localized at the metal/semiconductor （M/S） interface. The effect of Rs on C and G is found considerably high especially at high frequencies. Therefore, the high frequencies of the values of C and G were corrected for the effect of Rs in the whole measured bias range to obtain the real diode capacitance Cc and conductance Gc using the Nicollian and Goetzberger technique. The distribution profile of Rs-V gives a peak depending on the frequency especially at low frequencies and disappears with increasing frequencies due to the existence of Nss at the M/S interface.展开更多
Dynamic characteristics of the single-crystal Ga N-passivated lateral AlGaN/GaN Schottky barrier diodes(SBDs)treated with proton irradiation are investigated.Radiation-induced changes including idealized Schottky inte...Dynamic characteristics of the single-crystal Ga N-passivated lateral AlGaN/GaN Schottky barrier diodes(SBDs)treated with proton irradiation are investigated.Radiation-induced changes including idealized Schottky interface and slightly degraded on-resistance(RON)are observed under 10-Me V proton irradiation at a fluence of 10^(14)cm^(-2).Because of the existing negative polarization charges induced at GaN/AlGaN interface,the dynamic ON-resistance(RON,dyn)shows negligible degradation after a 1000-s-long forward current stress of 50 mA to devices with and without being irradiated by protons.Furthermore,the normalized RON,dynincreases by only 14%that of the initial case after a 100-s-long bias of-600 V has been applied to the irradiated devices.The high-performance lateral AlGaN/GaN SBDs with tungsten as anode metal and in-situ single-crystal GaN as passivation layer show a great potential application in the harsh radiation environment of space.展开更多
针对仿真设计(Simulation Based Design,SBD)技术在船型设计中应用存在局限性的问题,提出一种以SBD技术为基础的线型优化方法,为该技术在船型设计领域的广泛应用提供一种新思路。建立船体参数化模型;通过全局参数灵敏度分析,减小设计参...针对仿真设计(Simulation Based Design,SBD)技术在船型设计中应用存在局限性的问题,提出一种以SBD技术为基础的线型优化方法,为该技术在船型设计领域的广泛应用提供一种新思路。建立船体参数化模型;通过全局参数灵敏度分析,减小设计参数数量,缩小最优线型的搜索范围;在整个设计优化空间内完成对目标船阻力性能和推进性能的优化。将该方法应用于某大型液化气船线型研发项目中,结果表明,通过该方法得到的优化方案在设计航速点的收到功率相比初始线型降低5%以上,优化效果显著。该项目的成功开展表明该优化方法可靠、有效、易操作,可为后续全面实现以数值评估和目标函数寻优为主导的知识化、智能化设计模式提供参考。展开更多
We demonstrate superb large-area verticalβ-Ga_(2)O_(3)SBDs with a Schottky contact area of 1×1 mm^(2)and obtain a high-efficiency DC-DC converter based on the device.Theβ-Ga_(2)O_(3)SBD can obtain a forward cur...We demonstrate superb large-area verticalβ-Ga_(2)O_(3)SBDs with a Schottky contact area of 1×1 mm^(2)and obtain a high-efficiency DC-DC converter based on the device.Theβ-Ga_(2)O_(3)SBD can obtain a forward current of 8 A with a forward volt-age of 5 V,and has a reverse breakdown voltage of 612 V.The forward turn-on voltage(VF)and the on-resistance(Ron)are 1.17 V and 0.46Ω,respectively.The conversion efficiency of theβ-Ga_(2)O_(3)SBD-based DC-DC converter is 95.81%.This work indicates the great potential of Ga_(2)O_(3)SBDs and relevant circuits in power electronic applications.展开更多
In this work,W/β-Ga_(2)O_(3)Schottky barrier diodes,prepared using a confined magnetic field-based sputtering method,were analyzed at different operation temperatures.Firstly,Schottky barrier height increased with in...In this work,W/β-Ga_(2)O_(3)Schottky barrier diodes,prepared using a confined magnetic field-based sputtering method,were analyzed at different operation temperatures.Firstly,Schottky barrier height increased with increasing temperature from 100 to 300 K and reached 1.03 eV at room temperature.The ideality factor decreased with increasing temperature and it was higher than 2 at 100 K.This apparent high value was related to the tunneling effect.Secondly,the series and on-resistances decreased with increasing operation temperature.Finally,the interfacial dislocation was extracted from the tunneling current.A high dislocation density was found,which indicates the domination of tunneling through dislocation in the transport mecha-nism.These findings are evidently helpful in designing better performance devices.展开更多
A high-performance terahertz Schottky barrier diode(SBD)with an inverted trapezoidal epitaxial cross-sectional structure featuring high varactor characteristics and reverse breakdown characteristics is reported in thi...A high-performance terahertz Schottky barrier diode(SBD)with an inverted trapezoidal epitaxial cross-sectional structure featuring high varactor characteristics and reverse breakdown characteristics is reported in this paper.Inductively coupled plasma dry etching and dissolution wet etching are used to define the profile of the epitaxial layer,by which the voltage-dependent variation trend of the thickness of the metal-semiconductor contact depletion layer is modified.The simulation of the inverted trapezoidal epitaxial cross-section SBD is also conducted to explain the physical mechanism of the electric field and space charge region area.Compared with the normal structure,the grading coefficient M increases from 0.47 to 0.52,and the capacitance modulation ratio(C^(max)/C_(min))increases from 6.70 to 7.61.The inverted trapezoidal epitaxial cross-section structure is a promising approach to improve the variable-capacity ratio by eliminating the accumulation of charge at the Schottky electrode edge.A 190 GHz frequency doubler based on the inverted trapezoidal epitaxial cross-section SBD also shows a doubling efficiency of 35%compared to that 30%of a normal SBD.展开更多
随着计算机技术的飞速发展以及最优化理论的不断完善,最优化技术已被引入船舶设计领域,并与先进的CFD技术成功结合,发展形成了崭新的SBD(Simulation Based Design)技术,该技术为船型优化设计和构型船型打开了新的局面,在国际船舶研究设...随着计算机技术的飞速发展以及最优化理论的不断完善,最优化技术已被引入船舶设计领域,并与先进的CFD技术成功结合,发展形成了崭新的SBD(Simulation Based Design)技术,该技术为船型优化设计和构型船型打开了新的局面,在国际船舶研究设计领域引起了广泛的关注。文中对船舶领域中的SBD技术的基本内涵及其所包含的主要关键技术进行了阐述和总结,同时对国内外该研究方向的发展现状与趋势进行了分析和评述。展开更多
基金supported by the Scientific and Technological Research Council of Turkey (TUBITAK)
文摘The frequency dependent of the forward and reverse bias capacitance-voltage （C-V） and conductance-voltage （G/w-V） charac- teristics of Au/p-InP SBDs have been investigated in the frequency range of 20 kHz-10 MHz and voltage range of-5 - 5 V at room temperature. The effects of surface states （Nss） and series resistance （R0 on C-V and G/w-V characteristics have been in- vestigated in detail. The frequency dependent Nss and Rs profiles were obtained for various applied bias voltages. The experi- mental results show that the main electrical parameters of Au/p-InP SBD such as barrier height （gOB）, the density of acceptor concentration （NA）, Nss and Rs were found strongly frequency and voltage dependent. The values of C and G/w decrease with increasing frequency due to a continuous distribution of Nss localized at the metal/semiconductor （M/S） interface. The effect of Rs on C and G is found considerably high especially at high frequencies. Therefore, the high frequencies of the values of C and G were corrected for the effect of Rs in the whole measured bias range to obtain the real diode capacitance Cc and conductance Gc using the Nicollian and Goetzberger technique. The distribution profile of Rs-V gives a peak depending on the frequency especially at low frequencies and disappears with increasing frequencies due to the existence of Nss at the M/S interface.
基金Project supported by the National Natural Science Foundation of China(Grant No.62104185)the Fundamental Research Funds for the Central Universities,China(Grant No.JB211103)+1 种基金the National Natural Science Foundation for Distinguished Young Scholars,China(Grant No.61925404)the Wuhu and Xidian University Special Fund for Industry–University-Research Cooperation,China(Grant No.XWYCXY-012021010)。
文摘Dynamic characteristics of the single-crystal Ga N-passivated lateral AlGaN/GaN Schottky barrier diodes(SBDs)treated with proton irradiation are investigated.Radiation-induced changes including idealized Schottky interface and slightly degraded on-resistance(RON)are observed under 10-Me V proton irradiation at a fluence of 10^(14)cm^(-2).Because of the existing negative polarization charges induced at GaN/AlGaN interface,the dynamic ON-resistance(RON,dyn)shows negligible degradation after a 1000-s-long forward current stress of 50 mA to devices with and without being irradiated by protons.Furthermore,the normalized RON,dynincreases by only 14%that of the initial case after a 100-s-long bias of-600 V has been applied to the irradiated devices.The high-performance lateral AlGaN/GaN SBDs with tungsten as anode metal and in-situ single-crystal GaN as passivation layer show a great potential application in the harsh radiation environment of space.
文摘针对仿真设计(Simulation Based Design,SBD)技术在船型设计中应用存在局限性的问题,提出一种以SBD技术为基础的线型优化方法,为该技术在船型设计领域的广泛应用提供一种新思路。建立船体参数化模型;通过全局参数灵敏度分析,减小设计参数数量,缩小最优线型的搜索范围;在整个设计优化空间内完成对目标船阻力性能和推进性能的优化。将该方法应用于某大型液化气船线型研发项目中,结果表明,通过该方法得到的优化方案在设计航速点的收到功率相比初始线型降低5%以上,优化效果显著。该项目的成功开展表明该优化方法可靠、有效、易操作,可为后续全面实现以数值评估和目标函数寻优为主导的知识化、智能化设计模式提供参考。
基金supported by the National Natural Science Foundation of China (NSFC) under Grant Nos. 61925110, 61821091, 62004184 and 62234007the Key-Area Research and Development Program of Guangdong Province under Grant No. 2020B010174002
文摘We demonstrate superb large-area verticalβ-Ga_(2)O_(3)SBDs with a Schottky contact area of 1×1 mm^(2)and obtain a high-efficiency DC-DC converter based on the device.Theβ-Ga_(2)O_(3)SBD can obtain a forward current of 8 A with a forward volt-age of 5 V,and has a reverse breakdown voltage of 612 V.The forward turn-on voltage(VF)and the on-resistance(Ron)are 1.17 V and 0.46Ω,respectively.The conversion efficiency of theβ-Ga_(2)O_(3)SBD-based DC-DC converter is 95.81%.This work indicates the great potential of Ga_(2)O_(3)SBDs and relevant circuits in power electronic applications.
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2020R1A2C1013693)the Technology Innovation Program (20016102, Development of 1.2k V Gallium oxide power semiconductor devices technology and RS2022-00144027, Development of 1.2k V-class low-loss gallium oxide transistor) by the Ministry of Trade, Industry, and Energy (MOTIE, Korea)
文摘In this work,W/β-Ga_(2)O_(3)Schottky barrier diodes,prepared using a confined magnetic field-based sputtering method,were analyzed at different operation temperatures.Firstly,Schottky barrier height increased with increasing temperature from 100 to 300 K and reached 1.03 eV at room temperature.The ideality factor decreased with increasing temperature and it was higher than 2 at 100 K.This apparent high value was related to the tunneling effect.Secondly,the series and on-resistances decreased with increasing operation temperature.Finally,the interfacial dislocation was extracted from the tunneling current.A high dislocation density was found,which indicates the domination of tunneling through dislocation in the transport mecha-nism.These findings are evidently helpful in designing better performance devices.
基金Project supported by the National Natural Science Foundation of China (Grant No.61871072)。
文摘A high-performance terahertz Schottky barrier diode(SBD)with an inverted trapezoidal epitaxial cross-sectional structure featuring high varactor characteristics and reverse breakdown characteristics is reported in this paper.Inductively coupled plasma dry etching and dissolution wet etching are used to define the profile of the epitaxial layer,by which the voltage-dependent variation trend of the thickness of the metal-semiconductor contact depletion layer is modified.The simulation of the inverted trapezoidal epitaxial cross-section SBD is also conducted to explain the physical mechanism of the electric field and space charge region area.Compared with the normal structure,the grading coefficient M increases from 0.47 to 0.52,and the capacitance modulation ratio(C^(max)/C_(min))increases from 6.70 to 7.61.The inverted trapezoidal epitaxial cross-section structure is a promising approach to improve the variable-capacity ratio by eliminating the accumulation of charge at the Schottky electrode edge.A 190 GHz frequency doubler based on the inverted trapezoidal epitaxial cross-section SBD also shows a doubling efficiency of 35%compared to that 30%of a normal SBD.
文摘随着计算机技术的飞速发展以及最优化理论的不断完善,最优化技术已被引入船舶设计领域,并与先进的CFD技术成功结合,发展形成了崭新的SBD(Simulation Based Design)技术,该技术为船型优化设计和构型船型打开了新的局面,在国际船舶研究设计领域引起了广泛的关注。文中对船舶领域中的SBD技术的基本内涵及其所包含的主要关键技术进行了阐述和总结,同时对国内外该研究方向的发展现状与趋势进行了分析和评述。
