The samples of InxGa（1-x）As/In（0.52）Al（0.48）As two-dimensional electron gas（2DEG）are grown by molecular beam epitaxy（MBE）.In the sample preparation process,the In content and spacer layer thickness are chang...The samples of InxGa（1-x）As/In（0.52）Al（0.48）As two-dimensional electron gas（2DEG）are grown by molecular beam epitaxy（MBE）.In the sample preparation process,the In content and spacer layer thickness are changed and two kinds of methods,i.e.,contrast body doping andδ-doping are used.The samples are analyzed by the Hall measurements at 300 Kand 77 K.The InxGa1-xAs/In0.52Al0.48As 2DEG channel structures with mobilities as high as 10289 cm^2/V·s（300 K）and42040 cm^2/V·s（77 K）are obtained,and the values of carrier concentration（Nc）are 3.465×10^12/cm^2 and 2.502×10^12/cm^2,respectively.The THz response rates of In P-based high electron mobility transistor（HEMT）structures with different gate lengths at 300 K and 77 K temperatures are calculated based on the shallow water wave instability theory.The results provide a reference for the research and preparation of In P-based HEMT THz detectors.展开更多
The growth of the InAs film directly on the Si substrate deflected from the plane(100) at 4° towards(110) has been performed using a two-step procedure. The effect of the growth and annealing temperature on the e...The growth of the InAs film directly on the Si substrate deflected from the plane(100) at 4° towards(110) has been performed using a two-step procedure. The effect of the growth and annealing temperature on the electron mobility and surface topography has been investigated for a set of samples. The results show that the highest electron mobility is4640 cm^2/V·s in the sample, in which the 10-nm InAs nucleation layer is grown at a low temperature of 320 ℃ followed by ramping up to 560 ℃, and the nucleation layer was annealed for 15 min and the second layer of InAs is grown at 520 ℃.The influence of different buffer layers on the electron mobility of the samples has also been investigated, which shows that the highest electron mobility of 9222 cm^2/V·s at 300 K is obtained in the sample grown on a thick and linearly graded InGaAlAs metamorphic buffer layer deposited at 420 ℃.展开更多
The InAs/AlSb heterostructures with step-graded GaAsxSb1-x metamorphic buffer layers grown on Si substrates by molecular beam epitaxy are studied. The step-graded GaAsxSb1-x metamorphic buffer layers are used to relax...The InAs/AlSb heterostructures with step-graded GaAsxSb1-x metamorphic buffer layers grown on Si substrates by molecular beam epitaxy are studied. The step-graded GaAsxSb1-x metamorphic buffer layers are used to relax the strain and block defects at each interface of the layers. Meanwhile, adding Sb to GaAs is also beneficial to suppressing the formation of dislocations in the subsequent materials. The influences of the growth temperature of the step-graded GaAsxSb1-x metamorphic buffer layer on the electron mobility and surface topography are investigated for a series of samples. Based on the atomic force microscopy（AFM）, high resolution x-ray diffraction（HRXRD）, reciprocal space map（RSM）, and Hall measurements, the crystal quality and composition of GaAsxSb1-x layer are seen to strongly depend on growth temperature while keeping the Ga growth rate and V/III ratio constant. The results show that the highest electron mobility is 10270 cm2/V·s and the roughness is 4.3 nm for the step-graded GaAsxSb1-x metamorphic buffer layer grown at a temperature of 410℃.展开更多
基金Project supported by the Foundation for Scientific Instrument and Equipment Development,Chinese Academy of Sciences(Grant No.YJKYYQ20170032)the National Natural Science Foundation of China(Grant No.61435012)
文摘The samples of InxGa（1-x）As/In（0.52）Al（0.48）As two-dimensional electron gas（2DEG）are grown by molecular beam epitaxy（MBE）.In the sample preparation process,the In content and spacer layer thickness are changed and two kinds of methods,i.e.,contrast body doping andδ-doping are used.The samples are analyzed by the Hall measurements at 300 Kand 77 K.The InxGa1-xAs/In0.52Al0.48As 2DEG channel structures with mobilities as high as 10289 cm^2/V·s（300 K）and42040 cm^2/V·s（77 K）are obtained,and the values of carrier concentration（Nc）are 3.465×10^12/cm^2 and 2.502×10^12/cm^2,respectively.The THz response rates of In P-based high electron mobility transistor（HEMT）structures with different gate lengths at 300 K and 77 K temperatures are calculated based on the shallow water wave instability theory.The results provide a reference for the research and preparation of In P-based HEMT THz detectors.
基金Project supported by the National Defense Advanced Research Project,China(Grant No.315 xxxxx301)National Defense Innovation Program,China(Grant No.48xx4)+2 种基金the National Key Technologies Research and Development Program of China(Grant No.2018YFA03xxx01)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.YJKYYQ2017xxx2)the National Natural Science Foundation of China(Grant No.6150xxx6)
文摘The growth of the InAs film directly on the Si substrate deflected from the plane(100) at 4° towards(110) has been performed using a two-step procedure. The effect of the growth and annealing temperature on the electron mobility and surface topography has been investigated for a set of samples. The results show that the highest electron mobility is4640 cm^2/V·s in the sample, in which the 10-nm InAs nucleation layer is grown at a low temperature of 320 ℃ followed by ramping up to 560 ℃, and the nucleation layer was annealed for 15 min and the second layer of InAs is grown at 520 ℃.The influence of different buffer layers on the electron mobility of the samples has also been investigated, which shows that the highest electron mobility of 9222 cm^2/V·s at 300 K is obtained in the sample grown on a thick and linearly graded InGaAlAs metamorphic buffer layer deposited at 420 ℃.
基金Project supported by the National Defense Advanced Research Project,China(Grant No.315 xxxxx301)the National Defense Innovation Program,China(Grant No.48xx4)+2 种基金the National Key Technologies Research and Development Program,China(Grant No.2018YFA0306101)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.YJKYYQ20170032)the National Natural Science Foundation of China(Grant No.61505196)
文摘The InAs/AlSb heterostructures with step-graded GaAsxSb1-x metamorphic buffer layers grown on Si substrates by molecular beam epitaxy are studied. The step-graded GaAsxSb1-x metamorphic buffer layers are used to relax the strain and block defects at each interface of the layers. Meanwhile, adding Sb to GaAs is also beneficial to suppressing the formation of dislocations in the subsequent materials. The influences of the growth temperature of the step-graded GaAsxSb1-x metamorphic buffer layer on the electron mobility and surface topography are investigated for a series of samples. Based on the atomic force microscopy（AFM）, high resolution x-ray diffraction（HRXRD）, reciprocal space map（RSM）, and Hall measurements, the crystal quality and composition of GaAsxSb1-x layer are seen to strongly depend on growth temperature while keeping the Ga growth rate and V/III ratio constant. The results show that the highest electron mobility is 10270 cm2/V·s and the roughness is 4.3 nm for the step-graded GaAsxSb1-x metamorphic buffer layer grown at a temperature of 410℃.
