| 1. |
- Hussain, Laiq, 1979-, et al.
(författare)
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SWIR-LWIR Photoluminescence from Sb-based Epilayers Grown on GaAs Substrates by using MBE
- 2018
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Ingår i: Journal of the Korean Physical Society. - : Korean Physical Society. - 0374-4884 .- 1976-8524. ; 73:11, s. 1604-1611
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Tidskriftsartikel (refereegranskat)abstract
- Utilizing Sb-based bulk epilayers on large-scale low-cost substrates such as GaAs for fabricating infrared (IR) photodetectors is presently attracting significant attention worldwide. For this study, three sample series of GaAsxSb1−x, In1−xGaxSb, and InAsxSb1−x with different compositions were grown on semi-insulating GaAs substrates by using molecular beam epitaxy (MBE) and appropriate InAs quantum dots (QDs) as a defect-reduction buffer layer. Photoluminescence (PL) signals from these samples were observed over a wide IR wavelength range from 2 μm to 12 μm in agreement with the expected bandgap, including bowing effects. In particular, interband PL signals from InAsxSb1−x and In1−xGaxSb samples even at room temperature show promising potential for IR photodetector applications.
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| 2. |
- Wang, Qin, et al.
(författare)
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MWIR interband transitions in type-II (III) In(GaAl)Sb quantum dots
- 2015
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Konferensbidrag (refereegranskat)abstract
- In this work we present an alternative approach for realizing desired IR devices with appropriate operating wavelengths in the MWIR region utilizing In(GaAl)Sb quantum dots embedded in an InAs matrix grown by MBE. The QDs exhibit spatially indirect interband transitions in a type-II broken bandgap alignment, with a transition energy that can be tuned by bandgap and strain engineering utilizing either the quantum dot size or the incorporation of Ga or (GaAl) into the QDs. Furthermore, the growth of such QDs does not require sophisticated epitaxial designs needed for superlattices or quantum cascade structures regarding large numbers of alternating layers and very exact interfaces. The QD structures are expected to exhibit key advantages for IR devices e.g. higher operating temperature, lower power consumption, size, weight, and cost. The structural and composition properties of designed and grown In(GaAl)Sb QDs were characterized using AFM, SEM, TEM, and XRD. The corresponding optical properties, both in terms of absorption and emission, were analyzed and compared for selected QD samples before and after annealing at 650 °C.
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