Growth and characterization of metamorphic InAs/GaSb tunnel heterojunction on GaAs by molecular beam epitaxy

Journal Article · Tue Jun 28 00:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4954794· OSTI ID:22596667

Liu, Jheng-Sin; Clavel, Michael B.; Pandey, Rahul ^[1]; Datta, Suman ^[2]; Meeker, Michael; Khodaparast, Giti A. ^[3]

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1. Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
2. Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
3. Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States)

The structural, morphological, optical, and electrical transport characteristics of a metamorphic, broken-gap InAs/GaSb p-i-n tunnel diode structure, grown by molecular beam epitaxy on GaAs, were demonstrated. Precise shutter sequences were implemented for the strain-balanced InAs/GaSb active layer growth on GaAs, as corroborated by high-resolution X-ray analysis. Cross-sectional transmission electron microscopy and detailed micrograph analysis demonstrated strain relaxation primarily via the formation of 90° Lomer misfit dislocations (MDs) exhibiting a 5.6 nm spacing and intermittent 60° MDs at the GaSb/GaAs heterointerface, which was further supported by a minimal lattice tilt of 180 arc sec observed during X-ray analysis. Selective area diffraction and Fast Fourier Transform patterns confirmed the full relaxation of the GaSb buffer layer and quasi-ideal, strain-balanced InAs/GaSb heteroepitaxy. Temperature-dependent photoluminescence measurements demonstrated the optical band gap of the GaSb layer. Strong optical signal at room temperature from this structure supports a high-quality material synthesis. Current–voltage characteristics of fabricated InAs/GaSb p-i-n tunnel diodes measured at 77 K and 290 K demonstrated two bias-dependent transport mechanisms. The Shockley–Read–Hall generation–recombination mechanism at low bias and band-to-band tunneling transport at high bias confirmed the p-i-n tunnel diode operation. This elucidated the importance of defect control in metamorphic InAs/GaSb tunnel diodes for the implementation of low-voltage and high-performance tunnel field effect transistor applications.

• OSTI ID: 22596667
• Journal Information: Journal of Applied Physics, Vol. 119, Issue 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BALANCES
DIFFRACTION
DISLOCATIONS
FIELD EFFECT TRANSISTORS
FOURIER TRANSFORM SPECTROMETERS
GALLIUM ANTIMONIDES
GALLIUM ARSENIDES
HETEROJUNCTIONS
INDIUM ARSENIDES
LAYERS
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
P-N JUNCTIONS
RELAXATION
STRAINS
TEMPERATURE DEPENDENCE
TRANSMISSION ELECTRON MICROSCOPY
TUNNEL DIODES
TUNNEL EFFECT
X RADIATION