For enhancement-mode InGaP/A1GaAs/InGaAs PHEMTs,gate annealing is conducted between gate structures of Ti/Pt/Au and Pt/Ti/Pt/Au. Comparison is made after thermal annealing and an optimum annealing process is ob- taine...For enhancement-mode InGaP/A1GaAs/InGaAs PHEMTs,gate annealing is conducted between gate structures of Ti/Pt/Au and Pt/Ti/Pt/Au. Comparison is made after thermal annealing and an optimum annealing process is ob- tained. Using the structure of Ti/Pt/Au, about a 200mV positive shift of threshold voltage is achieved by thermal annea- ling at 320℃ for 40min in N2 ambient. Finally, a stable and consistent enhancement-mode PHEMT is produced successfully with higher threshold voltage.展开更多
An extraction method of the component parameter values of an enhancement-mode InGaP/AIGaAs/In-GaAs PHEMT small signal equivalent circuit is presented,and these component parameter values are extracted by using the EEH...An extraction method of the component parameter values of an enhancement-mode InGaP/AIGaAs/In-GaAs PHEMT small signal equivalent circuit is presented,and these component parameter values are extracted by using the EEHEMT1 model of IC-CAP software. The extraction results are verified by ADS software,and the DC I-V curves and S parameters simulated by ADS are basically accordant with those of the test results. These results indicate that the EEHEMT1 model can be used for extracting the component parameters of an enhancement-mode PHEMT.展开更多
利用分子束外延 (MBE)技术在高指数面 Ga As衬底上自组织生长了应变 In Ga As/Ga As量子线材料。原子力显微镜 (AFM)观测结果表明量子线的密度高达 4× 1 0 5/cm。低温偏振光致发光谱 (PPL)研究发现其发光峰半高宽 (FWHM)最小为 9.2...利用分子束外延 (MBE)技术在高指数面 Ga As衬底上自组织生长了应变 In Ga As/Ga As量子线材料。原子力显微镜 (AFM)观测结果表明量子线的密度高达 4× 1 0 5/cm。低温偏振光致发光谱 (PPL)研究发现其发光峰半高宽 (FWHM)最小为 9.2 me V,最大偏振度可达 0 .2 2。以 Al Ga As为垫垒 ,In Ga As/Ga As量子线为沟道 ,成功制备了量子线场效应管 (QWR-FET)结构材料 ,并试制了器件 。展开更多
The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected sc...The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected scanning transmission electron microscopy(Cs-STEM)techniques.To facility our study,we grow two multiple quantum wells(MQWs)samples,which are almost identical except that in sample B a thin GaAs layer is inserted in each of the InGaAs well and AlGaAs barrier layer comparing to pristine InGaAs/AlGaAs MQWs(sample A).Our study indeed shows the direct evidences that In segregation occurs in the InGaAs/AlGaAs interface,and the effect of the Ga As insertion layer on suppressing the segregation of In atoms is also demonstrated on the atomic-scale.Therefore,the atomic-scale insights are provided to understand the segregation behavior of In atoms and to unravel the underlying mechanism of the effect of GaAs insertion layer on the improvement of crystallinity,interface roughness,and further an enhanced optical performance of InGaAs/AlGaAs QWs.展开更多
Strained InGaAs/GaAs quantum well (QW) was grown by low-pressuremetallorganic chemical vapor deposition (MOCVD). Growth interruption and strain buffer layer wereintroduced to improve the photoluminescence (PL) perform...Strained InGaAs/GaAs quantum well (QW) was grown by low-pressuremetallorganic chemical vapor deposition (MOCVD). Growth interruption and strain buffer layer wereintroduced to improve the photoluminescence (PL) performance of the InGaAs/GaAs quantum well. GoodPL results were obtained under condition of growth an interruption of 10 s combined with a moderatestrain buffer layer. Wavelength lasers of 1064 nm using the QW were grown and processed intodevices. Broad area lasers (100 μm x 500 μm) show very low threshold current densities (43 A/cm^2)and high slop efficiency (0.34 W/A, per facet).展开更多
文摘For enhancement-mode InGaP/A1GaAs/InGaAs PHEMTs,gate annealing is conducted between gate structures of Ti/Pt/Au and Pt/Ti/Pt/Au. Comparison is made after thermal annealing and an optimum annealing process is ob- tained. Using the structure of Ti/Pt/Au, about a 200mV positive shift of threshold voltage is achieved by thermal annea- ling at 320℃ for 40min in N2 ambient. Finally, a stable and consistent enhancement-mode PHEMT is produced successfully with higher threshold voltage.
文摘An extraction method of the component parameter values of an enhancement-mode InGaP/AIGaAs/In-GaAs PHEMT small signal equivalent circuit is presented,and these component parameter values are extracted by using the EEHEMT1 model of IC-CAP software. The extraction results are verified by ADS software,and the DC I-V curves and S parameters simulated by ADS are basically accordant with those of the test results. These results indicate that the EEHEMT1 model can be used for extracting the component parameters of an enhancement-mode PHEMT.
文摘利用分子束外延 (MBE)技术在高指数面 Ga As衬底上自组织生长了应变 In Ga As/Ga As量子线材料。原子力显微镜 (AFM)观测结果表明量子线的密度高达 4× 1 0 5/cm。低温偏振光致发光谱 (PPL)研究发现其发光峰半高宽 (FWHM)最小为 9.2 me V,最大偏振度可达 0 .2 2。以 Al Ga As为垫垒 ,In Ga As/Ga As量子线为沟道 ,成功制备了量子线场效应管 (QWR-FET)结构材料 ,并试制了器件 。
基金X.H.gratefully acknowledges the financial support from the National Natural Science Foundation of China(Grant No.21902096)the Scientific Research Foundation of Shaanxi University of Science and Technology(Grant No.126061803)+1 种基金S.M.and B.X.thank the National Natural Science Foundation of China(Grant No.21972103)the Shanxi Provincial Key Innovative Research Team in Science and Technology(Grant No.201703D111026).
文摘The In segregation and its suppression in InGaAs/AlGaAs quantum well are investigated by using high-resolution x-ray diffraction(XRD)and photoluminescence(PL),combined with the state-of-the-art aberration corrected scanning transmission electron microscopy(Cs-STEM)techniques.To facility our study,we grow two multiple quantum wells(MQWs)samples,which are almost identical except that in sample B a thin GaAs layer is inserted in each of the InGaAs well and AlGaAs barrier layer comparing to pristine InGaAs/AlGaAs MQWs(sample A).Our study indeed shows the direct evidences that In segregation occurs in the InGaAs/AlGaAs interface,and the effect of the Ga As insertion layer on suppressing the segregation of In atoms is also demonstrated on the atomic-scale.Therefore,the atomic-scale insights are provided to understand the segregation behavior of In atoms and to unravel the underlying mechanism of the effect of GaAs insertion layer on the improvement of crystallinity,interface roughness,and further an enhanced optical performance of InGaAs/AlGaAs QWs.
文摘Strained InGaAs/GaAs quantum well (QW) was grown by low-pressuremetallorganic chemical vapor deposition (MOCVD). Growth interruption and strain buffer layer wereintroduced to improve the photoluminescence (PL) performance of the InGaAs/GaAs quantum well. GoodPL results were obtained under condition of growth an interruption of 10 s combined with a moderatestrain buffer layer. Wavelength lasers of 1064 nm using the QW were grown and processed intodevices. Broad area lasers (100 μm x 500 μm) show very low threshold current densities (43 A/cm^2)and high slop efficiency (0.34 W/A, per facet).
