Mobility of the Two-Dimensional Electron Gas in DA-pHEMT Heterostructures with Various δ–n-Layer Profile Widths
- Authors: Protasov D.Y.1,2, Bakarov A.K.1,3, Toropov A.I.1,3, Ber B.Y.4, Kazantsev D.Y.4, Zhuravlev K.S.1,3
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Affiliations:
- Rzhanov Institute of Semiconductor Physics, Siberian Branch
- Novosibirsk State Technical University
- Novosibirsk State University
- Ioffe Institute
- Issue: Vol 52, No 1 (2018)
- Pages: 44-52
- Section: Semiconductor Structures, Low-Dimensional Systems, and Quantum Phenomena
- URL: https://journals.rcsi.science/1063-7826/article/view/202232
- DOI: https://doi.org/10.1134/S1063782618010189
- ID: 202232
Cite item
Abstract
The effect of the silicon-atom distribution profile in donor δ-layers of AlGaAs/InGaAs/AlGaAs heterostructures with donor–acceptor doping on the mobility of the two-dimensional electron gas is studied. The parameters of the δ-layer profiles are determined using the normal approximation of the spatial distributions of silicon atoms, measured by secondary-ion mass spectroscopy. It is shown that the standard deviation σ of the δ-layer profile can be reduced from 3.4 to 2.5 nm by the proper selection of growth conditions. Measurements of the magnetic-field dependences of the Hall effect and conductivity show that such a decrease in σ allowed an increase in the mobility of the two-dimensional electron gas in heterostructures by 4000 cm2/(V s) at 77 K and 600 cm2/(V s) at 300 K. The mobility calculation taking into account filling of the first two size-quantization subbands shows that an increase in the mobility is well explained by a reduction in the Coulomb scattering at ionized donors due to an increase in the effective thickness of the spacer layer with decreasing σ of the δ-layer profile.
About the authors
D. Yu. Protasov
Rzhanov Institute of Semiconductor Physics, Siberian Branch; Novosibirsk State Technical University
Author for correspondence.
Email: protasov@isp.nsc.ru
Russian Federation, Novosibirsk, 630090; Novosibirsk, 630073
A. K. Bakarov
Rzhanov Institute of Semiconductor Physics, Siberian Branch; Novosibirsk State University
Email: protasov@isp.nsc.ru
Russian Federation, Novosibirsk, 630090; Novosibirsk, 630090
A. I. Toropov
Rzhanov Institute of Semiconductor Physics, Siberian Branch; Novosibirsk State University
Email: protasov@isp.nsc.ru
Russian Federation, Novosibirsk, 630090; Novosibirsk, 630090
B. Ya. Ber
Ioffe Institute
Email: protasov@isp.nsc.ru
Russian Federation, St. Petersburg, 194021
D. Yu. Kazantsev
Ioffe Institute
Email: protasov@isp.nsc.ru
Russian Federation, St. Petersburg, 194021
K. S. Zhuravlev
Rzhanov Institute of Semiconductor Physics, Siberian Branch; Novosibirsk State University
Email: protasov@isp.nsc.ru
Russian Federation, Novosibirsk, 630090; Novosibirsk, 630090