In this paper, high material quality Al_(0.4) In_(0.6) AsSb quaternary alloy on GaSb substrates is demonstrated. The quality of these epilayers is assessed using a high-resolution x-ray diffraction, Fourier transform ...In this paper, high material quality Al_(0.4) In_(0.6) AsSb quaternary alloy on GaSb substrates is demonstrated. The quality of these epilayers is assessed using a high-resolution x-ray diffraction, Fourier transform infrared(FTIR) spectrometer,and atomic force microscope(AFM). The x-ray diffraction exhibits high order satellite peaks with a measured period of 31.06 ?(theoretical value is 30.48 ?), the mismatch between the GaSb substrate and AlInAsSb achieves-162 arcsec,and the root-mean square(RMS) roughness for typical material growths has achieved around 1.6 ? over an area of 10 μm×10 μm. At room temperature, the photoluminescence(PL) spectrum shows a cutoff wavelength of 1.617 μm.展开更多
We compared the photoluminescence(PL)properties of Al In As Sb digital alloy samples with different periods grown on Ga Sb(001)substrates by molecular beam epitaxy.Temperature-dependent S-shape behavior is observed an...We compared the photoluminescence(PL)properties of Al In As Sb digital alloy samples with different periods grown on Ga Sb(001)substrates by molecular beam epitaxy.Temperature-dependent S-shape behavior is observed and explained using a thermally activated redistribution model within a Gaussian distribution of localized states.There are two different mechanisms for the origin of the PL intensity quenching for the Al In As Sb digital alloy.The high-temperature activation energy E_(1)is positively correlated with the interface thickness,whereas the low-temperature activation energy E_(2)is negatively correlated with the interface thickness.A quantitative high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)study shows that the interface quality improves as the interface thickness increases.Our results confirm that E_(1)comes from carrier trapping at a state in the In Sb interface layer,while E_(2)originates from the exciton binding energy due to the roughness of the Al As interface layer.展开更多
Avalanche photodiodes fabricated from AlInAsSb grown as a digital alloy exhibit low excess noise.In this article,we investigate the band structurerelated mechanisms that influence impact ionization.Band-structures cal...Avalanche photodiodes fabricated from AlInAsSb grown as a digital alloy exhibit low excess noise.In this article,we investigate the band structurerelated mechanisms that influence impact ionization.Band-structures calculated using an empirical tight-binding method and Monte Carlo simulations reveal that the mini-gaps in the conduction band do not inhibit electron impact ionization.Good agreement between the full band Monte Carlo simulations and measured noise characteristics is demonstrated.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61774130 11474248,61176127,61006085,61274013,and 61306013the Key Program for International Science and Technology Cooperation Projects of China(Grant No.2011DFA62380)the Ph.D. Programs Foundation of the Ministry of Education of China(Grant No.20105303120002)
文摘In this paper, high material quality Al_(0.4) In_(0.6) AsSb quaternary alloy on GaSb substrates is demonstrated. The quality of these epilayers is assessed using a high-resolution x-ray diffraction, Fourier transform infrared(FTIR) spectrometer,and atomic force microscope(AFM). The x-ray diffraction exhibits high order satellite peaks with a measured period of 31.06 ?(theoretical value is 30.48 ?), the mismatch between the GaSb substrate and AlInAsSb achieves-162 arcsec,and the root-mean square(RMS) roughness for typical material growths has achieved around 1.6 ? over an area of 10 μm×10 μm. At room temperature, the photoluminescence(PL) spectrum shows a cutoff wavelength of 1.617 μm.
基金Project supported by the National Key Technologies Research and Development Program of China(Grant Nos.2019YFA0705203,2019YFA070104,2018YFA0209102,and 2018YFA0209104)the Major Program of the National Natural Science Foundation of China(Grant Nos.61790581,62004189,and 61274013)+2 种基金the Aeronautical Science Foundation of China(Grant No.20182436004)the Key Research Program of the Chinese Academy of Sciences(Grant No.XDPB22)the Research Foundation for Advanced Talents of the Chinese Academy of Sciences(Grant No.E27RBB03)。
文摘We compared the photoluminescence(PL)properties of Al In As Sb digital alloy samples with different periods grown on Ga Sb(001)substrates by molecular beam epitaxy.Temperature-dependent S-shape behavior is observed and explained using a thermally activated redistribution model within a Gaussian distribution of localized states.There are two different mechanisms for the origin of the PL intensity quenching for the Al In As Sb digital alloy.The high-temperature activation energy E_(1)is positively correlated with the interface thickness,whereas the low-temperature activation energy E_(2)is negatively correlated with the interface thickness.A quantitative high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)study shows that the interface quality improves as the interface thickness increases.Our results confirm that E_(1)comes from carrier trapping at a state in the In Sb interface layer,while E_(2)originates from the exciton binding energy due to the roughness of the Al As interface layer.
基金Army Research Office,Grant/Award Number:W911NF-17-1-0065Defense Advanced Research Projects Agency,Grant/Award Number:GG11972.153060。
文摘Avalanche photodiodes fabricated from AlInAsSb grown as a digital alloy exhibit low excess noise.In this article,we investigate the band structurerelated mechanisms that influence impact ionization.Band-structures calculated using an empirical tight-binding method and Monte Carlo simulations reveal that the mini-gaps in the conduction band do not inhibit electron impact ionization.Good agreement between the full band Monte Carlo simulations and measured noise characteristics is demonstrated.
