InA1As/InGaAs high electron mobility transistors （HEMTs） on an InP substrate with well-balanced cutoff frequency fT and maximum oscillation frequency frnax are reported. An InA1As/InGaAs HEMT with 100-nm gate length...InA1As/InGaAs high electron mobility transistors （HEMTs） on an InP substrate with well-balanced cutoff frequency fT and maximum oscillation frequency frnax are reported. An InA1As/InGaAs HEMT with 100-nm gate length and gate width of 2 × 50 μm shows excellent DC characteristics, including full channel current of 724 mA/mm, extrinsic maximum transconductance gm.max of 1051 mS/mm, and drain-gate breakdown voltage BVDG of 5.92 V. In addition, this device exhibits fT = 249 GHz and fmax = 415 GHz. These results were obtained by fabricating an asymmetrically recessed gate and minimizing the parasitic resistances. The specific Ohmic contact resistance was reduced to 0.031 0.mm. Moreover, the fT obtained in this work is the highest ever reported in 100-nm gate length InA1As/InGaAs InP-based HEMTs. The outstanding gm.max, fT, fmax, and good BVDG make the device suitable for applications in low noise amplifiers, power amplifiers, and high speed circuits.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
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
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
A simulation method for the thermal analysis of InAlAs/InGaAs/InP mid-infrared quantum cascade lasers (QCLs) based on finite-element method (FEM) is presented. The thermal distribution of the QCLs on substrate-side or...A simulation method for the thermal analysis of InAlAs/InGaAs/InP mid-infrared quantum cascade lasers (QCLs) based on finite-element method (FEM) is presented. The thermal distribution of the QCLs on substrate-side or epilayer-side mounting forms is simulated and the results are compared. Results show that the epilayer-side mounting form has much better heat dissipation capability than the substrate-side mounting.展开更多
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National Basic Research Program of China(2012CB619202)the Founding of CAS Key Laboratory of Infrared Imaging Materials and DetectorsInnovative Founding of Shanghai Institute of Microsystem and Information Technology,CAS
基金Project supported by the National Basic Research Program of China(Grant No.2010CB327502)
文摘InA1As/InGaAs high electron mobility transistors （HEMTs） on an InP substrate with well-balanced cutoff frequency fT and maximum oscillation frequency frnax are reported. An InA1As/InGaAs HEMT with 100-nm gate length and gate width of 2 × 50 μm shows excellent DC characteristics, including full channel current of 724 mA/mm, extrinsic maximum transconductance gm.max of 1051 mS/mm, and drain-gate breakdown voltage BVDG of 5.92 V. In addition, this device exhibits fT = 249 GHz and fmax = 415 GHz. These results were obtained by fabricating an asymmetrically recessed gate and minimizing the parasitic resistances. The specific Ohmic contact resistance was reduced to 0.031 0.mm. Moreover, the fT obtained in this work is the highest ever reported in 100-nm gate length InA1As/InGaAs InP-based HEMTs. The outstanding gm.max, fT, fmax, and good BVDG make the device suitable for applications in low noise amplifiers, power amplifiers, and high speed circuits.
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.
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.
文摘A simulation method for the thermal analysis of InAlAs/InGaAs/InP mid-infrared quantum cascade lasers (QCLs) based on finite-element method (FEM) is presented. The thermal distribution of the QCLs on substrate-side or epilayer-side mounting forms is simulated and the results are compared. Results show that the epilayer-side mounting form has much better heat dissipation capability than the substrate-side mounting.
