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

Abstract

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-performancemore » tunnel field effect transistor applications.« less

Authors:
; ;  [1];  [2];  [3]; ;  [4]
  1. Advanced Devices and Sustainable Energy Laboratory (ADSEL), Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)
  2. Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
  3. Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
  4. Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States)
Publication Date:
OSTI Identifier:
22596667
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
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

Citation Formats

Liu, Jheng-Sin, Clavel, Michael B., Hudait, Mantu K., E-mail: mantu.hudait@vt.edu, Pandey, Rahul, Datta, Suman, Meeker, Michael, and Khodaparast, Giti A.. Growth and characterization of metamorphic InAs/GaSb tunnel heterojunction on GaAs by molecular beam epitaxy. United States: N. p., 2016. Web. doi:10.1063/1.4954794.
Liu, Jheng-Sin, Clavel, Michael B., Hudait, Mantu K., E-mail: mantu.hudait@vt.edu, Pandey, Rahul, Datta, Suman, Meeker, Michael, & Khodaparast, Giti A.. Growth and characterization of metamorphic InAs/GaSb tunnel heterojunction on GaAs by molecular beam epitaxy. United States. doi:10.1063/1.4954794.
Liu, Jheng-Sin, Clavel, Michael B., Hudait, Mantu K., E-mail: mantu.hudait@vt.edu, Pandey, Rahul, Datta, Suman, Meeker, Michael, and Khodaparast, Giti A.. 2016. "Growth and characterization of metamorphic InAs/GaSb tunnel heterojunction on GaAs by molecular beam epitaxy". United States. doi:10.1063/1.4954794.
@article{osti_22596667,
title = {Growth and characterization of metamorphic InAs/GaSb tunnel heterojunction on GaAs by molecular beam epitaxy},
author = {Liu, Jheng-Sin and Clavel, Michael B. and Hudait, Mantu K., E-mail: mantu.hudait@vt.edu and Pandey, Rahul and Datta, Suman and Meeker, Michael and Khodaparast, Giti A.},
abstractNote = {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.},
doi = {10.1063/1.4954794},
journal = {Journal of Applied Physics},
number = 24,
volume = 119,
place = {United States},
year = 2016,
month = 6
}
  • The molecular beam epitaxial growth and characteristics of 1.45 {mu}m metamorphic InAs quantum dot tunnel injection lasers on GaAs have been studied. Under optimized growth conditions, the quantum dots exhibit photoluminescence linewidths {approx}30 meV and high intensity at room temperature. The lasers are characterized by ultralow threshold current (63 A/cm{sup 2}), large frequency response (f{sub -3dB}=8 GHz), and near-zero {alpha} parameter and chirp.
  • Epitaxial InAs:Sn is grown on semi-insulating GaAs substrates by molecular-beam epitaxy. The large lattice mismatch between these materials (/similar to/7.1%) generates a high density of threading dislocations which propagate into the epitaxial film. Both plan-view and cross-sectional transmission electron microscopy techniques are used to investigate the generation and propagation of these dislocations. For films that exceed the critical thickness, the threading dislocation density is inversely proportional to the epilayer thickness. Epitaxial layers incorporating growth interrupts have lower overall defect densities, yet maintain defect reduction profiles similar to those observed in layers grown without the growth interrupt. Room-temperature mobilities for InAs:Snmore » epitaxial layers varied from 11 200 to 22 100 cm/sup 2//V s for epilayer thicknesses of 0.4 to 4.4 ..mu..m, respectively. The thickness dependence on the mobility is attributed to a multiplicity of factors including surface scattering, interfacial strain, surface accumulation, and the high interfacial dislocation density.« less
  • To improve the confinement of two-dimensional electron gas (2DEG) in AlGaN/GaN high electron mobility transistor (HEMT) heterostructures, AlGaN/GaN/AlGaN double heterojunction HEMT (DH-HEMT) heterostructures were grown using ammonia-MBE on 100-mm Si substrate. Prior to the growth, single heterojunction HEMT (SH-HEMT) and DH-HEMT heterostructures were simulated using Poisson-Schrödinger equations. From simulations, an AlGaN buffer with “Al” mole fraction of 10% in the DH-HEMT was identified to result in both higher 2DEG concentration (∼10{sup 13 }cm{sup −2}) and improved 2DEG confinement in the channel. Hence, this composition was considered for the growth of the buffer in the DH-HEMT heterostructure. Hall measurements showed a roommore » temperature 2DEG mobility of 1510 cm{sup 2}/V.s and a sheet carrier concentration (n{sub s}) of 0.97 × 10{sup 13 }cm{sup −2} for the DH-HEMT structure, while they are 1310 cm{sup 2}/V.s and 1.09 × 10{sup 13 }cm{sup −2}, respectively, for the SH-HEMT. Capacitance-voltage measurements confirmed the improvement in the confinement of 2DEG in the DH-HEMT heterostructure, which helped in the enhancement of its room temperature mobility. DH-HEMT showed 3 times higher buffer break-down voltage compared to SH-HEMT, while both devices showed almost similar drain current density. Small signal RF measurements on the DH-HEMT showed a unity current-gain cut-off frequency (f{sub T}) and maximum oscillation frequency (f{sub max}) of 22 and 25 GHz, respectively. Thus, overall, DH-HEMT heterostructure was found to be advantageous due to its higher buffer break-down voltages compared to SH-HEMT heterostructure.« less
  • The molecular-beam epitaxial growth conditions of (N + 1)(InAs){sub m}/N(GaAsw){sub n} short period superlattices (SPSs) on GaAs substrates have been optimized. Hall electrical properties measured by the van der Pauw method were compared to low-temperature photoluminescence (77 K PL) spectra of GaAs/SPS/AlGaAs modulation-doped field-effect transistor-type heterostructures. By using these two characterization methods, the influences of the growth temperature T{sub s}, of the SPS channel thickness d{sub ch} and of its average indium composition y{sub m} were studied. Interesting correlations were established between their optical and their transport properties measured at 77 K either in the dark or under white-light illumination.more » The thickness m of the InAs layers was varied in the range 0.57 to 1.7 and sharp optimum properties were obtained slightly above m=1 monolayer.« less
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