The population of the third(n=3)two-dimensional electron subband of InGaAs/InAlAs modulation-doped structures has been observed by means of Fourier transform photoluminescence(PL).Three well resolved PL peaks centred ...The population of the third(n=3)two-dimensional electron subband of InGaAs/InAlAs modulation-doped structures has been observed by means of Fourier transform photoluminescence(PL).Three well resolved PL peaks centred at 0.737,0.908,and 0.980eV are observed,which are attributed to the transitions from the lowest three electron subbands to the n=1 heavy-hole subband.The subband separations clearly exhibiting the features of the stepped quantum well with triangle and square potentials are consistent with numerical calculation.Thanks to the presence of Fermi cutoff,the population ratio of these three subbands can be estimated.Temperature and excitation-dependent luminescences are also analyzed.展开更多
报道了用 MBE技术生长的 Ga As基 In Al As/In Ga As改变结构高电子迁移率晶体管 (MHEMT)的制作过程和器件的直流性能。对于栅长为 0 .8μm的器件 ,最大非本征跨导和饱和电流密度分别为 3 5 0 m S/mm和1 90 m A/mm。源漏击穿电压和栅反...报道了用 MBE技术生长的 Ga As基 In Al As/In Ga As改变结构高电子迁移率晶体管 (MHEMT)的制作过程和器件的直流性能。对于栅长为 0 .8μm的器件 ,最大非本征跨导和饱和电流密度分别为 3 5 0 m S/mm和1 90 m A/mm。源漏击穿电压和栅反向击穿电压分别为 4V和 7.5 V。这些直流特性超过了相同的材料和工艺条件下 Ga As基 PHEMT的水平 ,与 In P基 In Al As/In Ga As展开更多
A set of 100-nm gate-length In P-based high electron mobility transistors(HEMTs)were designed and fabricated with different gate offsets in gate recess.A novel technology was proposed for independent definition of gat...A set of 100-nm gate-length In P-based high electron mobility transistors(HEMTs)were designed and fabricated with different gate offsets in gate recess.A novel technology was proposed for independent definition of gate recess and T-shaped gate by electron beam lithography.DC and RF measurement was conducted.With the gate offset varying from drain side to source side,the maximum drain current(I_(ds,max))and transconductance(g_(m,max))increased.In the meantime,fTdecreased while f;increased,and the highest fmax of 1096 GHz was obtained.It can be explained by the increase of gate-source capacitance and the decrease of gate-drain capacitance and source resistance.Output conductance was also suppressed by gate offset toward source side.This provides simple and flexible device parameter selection for HEMTs of different usages.展开更多
InP-based high electron mobility transistors（HEMTs） will be affected by protons from different directions in space radiation applications. The proton irradiation effects on InAlAs/InGaAs hetero-junction structures o...InP-based high electron mobility transistors（HEMTs） will be affected by protons from different directions in space radiation applications. The proton irradiation effects on InAlAs/InGaAs hetero-junction structures of InP-based HEMTs are studied at incident angles ranging from 0 to 89.9° by SRIM software. With the increase of proton incident angle, the change trend of induced vacancy defects in the InAlAs/InGaAs hetero-junction region is consistent with the vacancy energy loss trend of incident protons. Namely, they both have shown an initial increase, followed by a decrease after incident angle has reached 30°. Besides, the average range and ultimate stopping positions of incident protons shift gradually from buffer layer to hetero-junction region, and then go up to gate metal. Finally, the electrical characteristics of InP-based HEMTs are investigated after proton irradiation at different incident angles by Sentaurus-TCAD. The induced vacancy defects are considered self-consistently through solving Poisson＇s and current continuity equations. Consequently, the extrinsic transconductance, pinch-off voltage and channel current demonstrate the most serious degradation at the incident angle of 30？, which can be accounted for the most severe carrier sheet density reduction under this condition.展开更多
基金Supported by the National Natural Science Foundation of China.
文摘The population of the third(n=3)two-dimensional electron subband of InGaAs/InAlAs modulation-doped structures has been observed by means of Fourier transform photoluminescence(PL).Three well resolved PL peaks centred at 0.737,0.908,and 0.980eV are observed,which are attributed to the transitions from the lowest three electron subbands to the n=1 heavy-hole subband.The subband separations clearly exhibiting the features of the stepped quantum well with triangle and square potentials are consistent with numerical calculation.Thanks to the presence of Fermi cutoff,the population ratio of these three subbands can be estimated.Temperature and excitation-dependent luminescences are also analyzed.
基金Natural Science Foundation of Shanghai(10ZR1436300)Innovative Foundation of Shanghai Institute of Microsystem and Information TechnologyFoundation of Key Laboratory of Infrared Imaging Materials and Detectors CAS
文摘报道了用 MBE技术生长的 Ga As基 In Al As/In Ga As改变结构高电子迁移率晶体管 (MHEMT)的制作过程和器件的直流性能。对于栅长为 0 .8μm的器件 ,最大非本征跨导和饱和电流密度分别为 3 5 0 m S/mm和1 90 m A/mm。源漏击穿电压和栅反向击穿电压分别为 4V和 7.5 V。这些直流特性超过了相同的材料和工艺条件下 Ga As基 PHEMT的水平 ,与 In P基 In Al As/In Ga As
基金Project supported by the National Nature Science Foundation of China(Grant No.61434006)。
文摘A set of 100-nm gate-length In P-based high electron mobility transistors(HEMTs)were designed and fabricated with different gate offsets in gate recess.A novel technology was proposed for independent definition of gate recess and T-shaped gate by electron beam lithography.DC and RF measurement was conducted.With the gate offset varying from drain side to source side,the maximum drain current(I_(ds,max))and transconductance(g_(m,max))increased.In the meantime,fTdecreased while f;increased,and the highest fmax of 1096 GHz was obtained.It can be explained by the increase of gate-source capacitance and the decrease of gate-drain capacitance and source resistance.Output conductance was also suppressed by gate offset toward source side.This provides simple and flexible device parameter selection for HEMTs of different usages.
基金Supported by the National Key Research and Development Program of China(2016YFB0402400)National Natural Science Foundation of China(61775228,61675225,and 61605232)the Shanghai Rising-Star Program(17QA1404900)
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11775191,61404115,61434006,and 11475256)the Program for Innovative Research Team(in Science and Technology)in University of Henan Province,China(Grant No.18IRTSTHN016)the Development Fund for Outstanding Young Teachers in Zhengzhou University of China(Grant No.1521317004)
文摘InP-based high electron mobility transistors（HEMTs） will be affected by protons from different directions in space radiation applications. The proton irradiation effects on InAlAs/InGaAs hetero-junction structures of InP-based HEMTs are studied at incident angles ranging from 0 to 89.9° by SRIM software. With the increase of proton incident angle, the change trend of induced vacancy defects in the InAlAs/InGaAs hetero-junction region is consistent with the vacancy energy loss trend of incident protons. Namely, they both have shown an initial increase, followed by a decrease after incident angle has reached 30°. Besides, the average range and ultimate stopping positions of incident protons shift gradually from buffer layer to hetero-junction region, and then go up to gate metal. Finally, the electrical characteristics of InP-based HEMTs are investigated after proton irradiation at different incident angles by Sentaurus-TCAD. The induced vacancy defects are considered self-consistently through solving Poisson＇s and current continuity equations. Consequently, the extrinsic transconductance, pinch-off voltage and channel current demonstrate the most serious degradation at the incident angle of 30？, which can be accounted for the most severe carrier sheet density reduction under this condition.
