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High Carrier Lifetimes in Epitaxial Germanium-Tin/Al(In)As Heterostructures with Variable Tin Compositions

Journal Article · · Journal of Materials Chemistry C
DOI:https://doi.org/10.1039/D2TC00830K· OSTI ID:1880807
Group IV-based germanium-tin (Ge1-ySny) compositional materials have recently shown great promise for infrared detection, light emission and ultra-low power transistors. High carrier lifetimes are desirable for enhancing the detection limit and efficiency of photodetectors, low threshold current density in lasers, and low tunneling barrier height by lowering defects and dislocations at the heterointerface of a source and a channel. Here, carrier lifetimes in epitaxial germanium (Ge) and variable tin (Sn) compositional Ge1-ySny materials were experimentally determined on GaAs substrates using the contactless microwave photoconductive decay (u-PCD) technique at an excitation wavelength of 1500 nm. Sharp (2 x 2) reflection high energy electron diffraction patterns and low surface roughness were observed from the surface of the Ge0.97Sn0.03 epilayer. X-ray rocking curves from Ge0.97Sn0.03 and Ge0.94Sn0.06 layers demonstrated the pseudomorphic and lattice-matched growth on AlAs and In0.12Al0.88As buffers, respectively, further substantiated by reciprocal space maps and abrupt heterointerfaces evident from the presence of Pendellosung oscillations. High effective carrier lifetimes of 150 ns to 450 ns were measured for Ge1-ySny epilayers as a function of Sn composition, surface roughness, growth temperature, and layer thickness. The observed increase in the carrier lifetime with an increasing Ge layer thickness and a reducing surface roughness, by incorporating Sn, were explained. The enhancement of the carrier lifetime with an increasing Sn concentration was achieved by controlling the defects with lattice-matched Ge0.94Sn0.06/In0.12Al0.88As heterointerfaces or the pseudomorphic growth of Ge0.94Sn0.06 on GaAs. Therefore, our monolithic integration of variable Sn alloy compositional Ge1-ySny materials with high carrier lifetimes opens avenues to realize electronic and optoelectronic devices.
Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE National Renewable Energy Laboratory (NREL); National Science Foundation (NSF)
DOE Contract Number:
AC36-08GO28308
OSTI ID:
1880807
Report Number(s):
NREL/JA-5K00-81502; MainId:82275; UUID:f9b6ee5f-a033-45d0-9dcc-b2ac24b435ae; MainAdminID:65069
Journal Information:
Journal of Materials Chemistry C, Journal Name: Journal of Materials Chemistry C Journal Issue: 29 Vol. 10
Country of Publication:
United States
Language:
English

References (59)

Impact of Threading Dislocations on the Design of GaAs and InGaP/GaAs Solar Cells on Si Using Finite Element Analysis journal January 2013
Optically Pumped GeSn Microdisk Lasers on Si journal July 2016
Roadmap to an Efficient Germanium-on-Silicon Laser: Strain vs. n-Type Doping journal October 2012
Lasing in direct-bandgap GeSn alloy grown on Si journal January 2015
Experimental Calibration of Sn-Related Varshni Parameters for High Sn Content GeSn Layers journal February 2019
Electronic and optical properties of highly boron-doped epitaxial Ge/AlAs(001) heterostructures journal February 2020
Ge1−ySny photoconductor structures at 1.55μm: From advanced materials to prototype devices
  • Roucka, R.; Xie, J.; Kouvetakis, J.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 26, Issue 6 https://doi.org/10.1116/1.3021024
journal November 2008
Simultaneous Measurement of Minority-Carrier Lifetime in Single-Crystal CdTe Using Three Transient Decay Techniques journal September 2014
An Energy-Efficient Tensile-Strained Ge/InGaAs TFET 7T SRAM Cell Architecture for Ultralow-Voltage Applications journal May 2017
Strain-Engineered Biaxial Tensile Epitaxial Germanium for High-Performance Ge/InGaAs Tunnel Field-Effect Transistors journal May 2015
Ge-Photodetectors for Si-Based Optoelectronic Integration journal January 2011
Impact of minority carrier lifetime on the performance of strained germanium light sources journal April 2016
Carrier Dynamics in Thin Germanium–Tin Epilayers journal January 2021
Enhanced radiative and thermal properties from surface encapsulation of InAs nanowires journal January 2021
Synthesis and Fundamental Studies of Si-Compatible (Si)GeSn and GeSn Mid-IR Systems with Ultrahigh Sn Contents journal November 2019
Tensile-Strained Nanoscale Ge/In 0.16 Ga 0.84 As Heterostructure for Tunnel Field-Effect Transistor journal March 2014
Molecular approaches to p- and n-nanoscale doping of Ge1−ySny semiconductors: Structural, electrical and transport properties journal August 2009
Temperature dependent spectral response and detectivity of GeSn photoconductors on silicon for short wave infrared detection journal January 2014
Achievable Performance of Uncooled Homojunction GeSn Mid-Infrared Photodetectors journal March 2022
Group IV Photonics: Driving Integrated Optoelectronics journal January 2016
Mid-infrared integrated photonics on silicon: a perspective journal December 2017
Observation of improved minority carrier lifetimes in high-quality Ge-on-insulator using time-resolved photoluminescence journal January 2014
Effects of Annealing on the Behavior of Sn in GeSn Alloy and GeSn-Based Photodetectors journal August 2020
Temperature dependent carrier lifetime, diffusion coefficient, and diffusion length in Ge 0.95 Sn 0.05 epilayer journal September 2020
Comparison of Silicon Photoluminescence and Photoconductive Decay for Material Quality Characterization journal January 2007
Advanced GeSn/SiGeSn Group IV Heterostructure Lasers journal March 2018
Carrier lifetime dependence on doping, metal implants and excitation density in Ge and Si journal December 2007
Mapping the Interfacial Electronic Structure of Strain-Engineered Epitaxial Germanium Grown on In x Al 1– x As Stressors journal February 2022
Systematic study of Si-based GeSn photodiodes with 26 µm detector cutoff for short-wave infrared detection journal January 2016
Perspective on the future of silicon photonics and electronics journal May 2021
Tensile-strained, n-type Ge as a gain medium for monolithic laser integration on Si journal January 2007
Enhanced GeSn Microdisk Lasers Directly Released on Si journal November 2021
Germanium tin: silicon photonics toward the mid-infrared [Invited] journal January 2013
Midinfrared Emission and Absorption in Strained and Relaxed Direct-Band-Gap Ge 1 − x Sn x Semiconductors journal February 2021
Indium content measurements in metamorphic high electron mobility transistor structures by combination of x-ray reciprocal space mapping and transmission electron microscopy journal April 2003
Group IV Light Sources to Enable the Convergence of Photonics and Electronics journal September 2014
Modeling of a SiGeSn quantum well laser journal January 2021
Performance Evaluation of Novel Strain-Engineered Ge-InGaAs Heterojunction Tunnel Field-Effect Transistors journal October 2015
Heterogeneously-Grown Tunable Tensile Strained Germanium on Silicon for Photonic Devices journal November 2015
Dependence of carrier lifetime in germanium on resisitivity and carrier injection level journal October 2006
Recent progress in lasers on silicon journal July 2010
Excess carrier lifetimes in Ge layers on Si journal February 2014
Engineering the Interfacial Electronic Structure of Epitaxial Ge/AlAs(001) Heterointerfaces via Substitutional Boron Incorporation: The Roles of Doping and Interface Stoichiometry journal November 2019
Carrier lifetime of GeSn measured by spectrally resolved picosecond photoluminescence spectroscopy journal January 2020
Perspectives on Advances in Quantum Dot Lasers and Integration with Si Photonic Integrated Circuits journal August 2021
Band engineering and growth of tensile strained Ge/(Si)GeSn heterostructures for tunnel field effect transistors journal May 2013
Si-Based GeSn Photodetectors toward Mid-Infrared Imaging Applications journal October 2019
Direct and indirect band gaps in Ge under biaxial tensile strain investigated by photoluminescence and photoreflectance studies journal May 2018
GeSn-on-Si normal incidence photodetectors with bandwidths more than 40 GHz journal January 2014
Ultrafast carrier recombination in highly n-doped Ge-on-Si films journal June 2019
Monolithically Integrated CMOS-Compatible III–V on Silicon Lasers journal November 2018
Optically Pumped GeSn Lasers Operating at 270 K with Broad Waveguide Structures on Si journal May 2019
Pseudopotential calculations of strained-GeSn/SiGeSn hetero-structures journal October 2014
Continuous-Wave Magneto-Optical Determination of the Carrier Lifetime in Coherent Ge 1 − x Sn x /Ge Heterostructures journal December 2020
Achieving direct band gap in germanium through integration of Sn alloying and external strain journal February 2013
Ultra-low-threshold continuous-wave and pulsed lasing in tensile-strained GeSn alloys journal March 2020
Towards monolithic integration of germanium light sources on silicon chips journal March 2016
Si based GeSn photoconductors with a 1.63 A/W peak responsivity and a 2.4  μ m long-wavelength cutoff journal December 2014
Monolithic infrared silicon photonics: The rise of (Si)GeSn semiconductors journal March 2021