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Title: Ultrafast carrier thermalization and trapping in silicon-germanium alloy probed by extreme ultraviolet transient absorption spectroscopy

Abstract

Semiconductor alloys containing silicon and germanium are of growing importance for compact and highly efficient photonic devices due to their favorable properties for direct integration into silicon platforms and wide tunability of optical parameters. Here, we report the simultaneous direct and energy-resolved probing of ultrafast electron and hole dynamics in a silicon-germanium alloy with the stoichiometry Si 0.25Ge 0.75 by extreme ultraviolet transient absorption spectroscopy. Probing the photoinduced dynamics of charge carriers at the germanium M 4,5-edge (~30 eV) allows the germanium atoms to be used as reporter atoms for carrier dynamics in the alloy. The photoexcitation of electrons across the direct and indirect band gap into conduction band (CB) valleys and their subsequent hot carrier relaxation are observed and compared to pure germanium, where the Ge direct (ΔE gap,Ge,direct = 0.8 eV) and Si 0.25Ge 0.75 indirect gaps (ΔE gap,Si0.25Ge0.75,indirect = 0.95 eV) are comparable in energy. In the alloy, comparable carrier lifetimes are observed for the X, L, and Γ valleys in the conduction band. A midgap feature associated with electrons accumulating in trap states near the CB edge following intraband thermalization is observed in the Si 0.25Ge 0.75 alloy. The successful implementation of the reporter atom conceptmore » for capturing the dynamics of the electronic bands by site-specific probing in solids opens a route to study carrier dynamics in more complex materials with femtosecond and sub-femtosecond temporal resolution.« less

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1];  [2];  [1];  [3];  [4];  [5];  [6]
  1. Univ. of California, Berkeley, CA (United States). Dept. of Chemistry
  2. Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). The Molecular Foundry
  4. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). The Molecular Foundry; SLAC National Accelerator Lab., Menlo Park, CA (United States). Theory Inst. for Materials and Energy Spectroscopies
  5. Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Chemical Sciences Division
  6. Univ. of California, Berkeley, CA (United States). Dept. of Chemistry. Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Chemical Sciences Division
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Energy Efficiency and Renewable Energy (EERE); US Army Research Office (ARO); US Air Force Office of Scientific Research (AFOSR); Defense Advanced Research Projects Agency (DARPA) (United States); USDOD; W. M. Keck Foundation (United States); Swiss National Science Foundation (SNSF)
OSTI Identifier:
1408443
Alternate Identifier(s):
OSTI ID: 1366565
Grant/Contract Number:  
AC02-05CH11231; AC03-76SF00098; AC02-76SF00515; WN911NF-14-1-0383; FA9550-15-1-0037; W31P4Q-13-1-0017; P2EZP2_165252
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Structural Dynamics
Additional Journal Information:
Journal Volume: 4; Journal Issue: 4; Journal ID: ISSN 2329-7778
Publisher:
American Crystallographic Association/AIP
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; germanium; elemental semiconductors; band gap; conduction bands; electron scattering

Citation Formats

Zürch, Michael, Chang, Hung-Tzu, Kraus, Peter M., Cushing, Scott K., Borja, Lauren J., Gandman, Andrey, Kaplan, Christopher J., Oh, Myoung Hwan, Prell, James S., Prendergast, David, Pemmaraju, Chaitanya D., Neumark, Daniel M., and Leone, Stephen R. Ultrafast carrier thermalization and trapping in silicon-germanium alloy probed by extreme ultraviolet transient absorption spectroscopy. United States: N. p., 2017. Web. doi:10.1063/1.4985056.
Zürch, Michael, Chang, Hung-Tzu, Kraus, Peter M., Cushing, Scott K., Borja, Lauren J., Gandman, Andrey, Kaplan, Christopher J., Oh, Myoung Hwan, Prell, James S., Prendergast, David, Pemmaraju, Chaitanya D., Neumark, Daniel M., & Leone, Stephen R. Ultrafast carrier thermalization and trapping in silicon-germanium alloy probed by extreme ultraviolet transient absorption spectroscopy. United States. https://doi.org/10.1063/1.4985056
Zürch, Michael, Chang, Hung-Tzu, Kraus, Peter M., Cushing, Scott K., Borja, Lauren J., Gandman, Andrey, Kaplan, Christopher J., Oh, Myoung Hwan, Prell, James S., Prendergast, David, Pemmaraju, Chaitanya D., Neumark, Daniel M., and Leone, Stephen R. Tue . "Ultrafast carrier thermalization and trapping in silicon-germanium alloy probed by extreme ultraviolet transient absorption spectroscopy". United States. https://doi.org/10.1063/1.4985056. https://www.osti.gov/servlets/purl/1408443.
@article{osti_1408443,
title = {Ultrafast carrier thermalization and trapping in silicon-germanium alloy probed by extreme ultraviolet transient absorption spectroscopy},
author = {Zürch, Michael and Chang, Hung-Tzu and Kraus, Peter M. and Cushing, Scott K. and Borja, Lauren J. and Gandman, Andrey and Kaplan, Christopher J. and Oh, Myoung Hwan and Prell, James S. and Prendergast, David and Pemmaraju, Chaitanya D. and Neumark, Daniel M. and Leone, Stephen R.},
abstractNote = {Semiconductor alloys containing silicon and germanium are of growing importance for compact and highly efficient photonic devices due to their favorable properties for direct integration into silicon platforms and wide tunability of optical parameters. Here, we report the simultaneous direct and energy-resolved probing of ultrafast electron and hole dynamics in a silicon-germanium alloy with the stoichiometry Si0.25Ge0.75 by extreme ultraviolet transient absorption spectroscopy. Probing the photoinduced dynamics of charge carriers at the germanium M4,5-edge (~30 eV) allows the germanium atoms to be used as reporter atoms for carrier dynamics in the alloy. The photoexcitation of electrons across the direct and indirect band gap into conduction band (CB) valleys and their subsequent hot carrier relaxation are observed and compared to pure germanium, where the Ge direct (ΔEgap,Ge,direct = 0.8 eV) and Si0.25Ge0.75 indirect gaps (ΔEgap,Si0.25Ge0.75,indirect = 0.95 eV) are comparable in energy. In the alloy, comparable carrier lifetimes are observed for the X, L, and Γ valleys in the conduction band. A midgap feature associated with electrons accumulating in trap states near the CB edge following intraband thermalization is observed in the Si0.25Ge0.75 alloy. The successful implementation of the reporter atom concept for capturing the dynamics of the electronic bands by site-specific probing in solids opens a route to study carrier dynamics in more complex materials with femtosecond and sub-femtosecond temporal resolution.},
doi = {10.1063/1.4985056},
url = {https://www.osti.gov/biblio/1408443}, journal = {Structural Dynamics},
issn = {2329-7778},
number = 4,
volume = 4,
place = {United States},
year = {2017},
month = {6}
}

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Cited by: 7 works
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Works referenced in this record:

Generalized Gradient Approximation Made Simple
journal, October 1996


The direct and indirect bandgaps of unstrained Si x Ge 1−x−y Sn y and their photonic device applications
journal, October 2012


Phonon-Assisted Optical Absorption in Silicon from First Principles
journal, April 2012


Theory of ultrafast phenomena in photoexcited semiconductors
journal, August 2002


Hydrogenated microcrystalline silicon germanium: A bottom cell material for amorphous silicon‐based tandem solar cells
journal, December 1996


Polarization-assisted amplitude gating as a route to tunable, high-contrast attosecond pulses
journal, January 2016


Carrier dynamics in semiconductors studied with time-resolved terahertz spectroscopy
journal, June 2011


QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials
journal, September 2009


Analysis of separable potentials
journal, October 1991


Statistics of the Recombinations of Holes and Electrons
journal, September 1952


Petahertz optical drive with wide-bandgap semiconductor
journal, April 2016


Role of mid-gap states in charge transport and photoconductivity in semiconductor nanocrystal films
journal, September 2011


Vibrational Spectra of Hydrogen in Silicon and Germanium
journal, August 1983


Near-band-gap photoluminescence of Si-Ge alloys
journal, September 1989


Silicon-based silicon–germanium–tin heterostructure photonics
journal, March 2014


Electroreflectance in Ge-Si alloys
text, January 1968


Ultrafast relaxation dynamics of charge carriers relaxation in ZnO nanocrystalline thin films
journal, March 2004


Attosecond Time-Resolved Autoionization of Argon
journal, October 2010


Deposition and Properties of Low-Pressure Chemical-Vapor Deposited Polycrystalline Silicon-Germanium Films
journal, January 1994


Lasing in direct-bandgap GeSn alloy grown on Si
journal, January 2015


Heterogeneous Integration of Compound Semiconductors
journal, June 2010


Direct and simultaneous observation of ultrafast electron and hole dynamics in germanium
journal, June 2017


Colloidal-quantum-dot photovoltaics using atomic-ligand passivation
journal, September 2011


Controlling dielectrics with the electric field of light
journal, December 2012


Optical-field-induced current in dielectrics
journal, December 2012


Non-radiative transitions in semiconductors
journal, December 1981


Core-level shifts of the Ge(100)-(2×1) surface and their origins
journal, June 1992


Density-Functional Theory for Time-Dependent Systems
journal, March 1984


Structural, optical, and spin properties of hydrogenated amorphous silicon‐germanium alloys
journal, July 1989


Atomic-Scale Perspective of Ultrafast Charge Transfer at a Dye–Semiconductor Interface
journal, July 2014


Real-Time Probing of Electron Dynamics Using Attosecond Time-Resolved Spectroscopy
journal, May 2016


Strong quantum-confined Stark effect in germanium quantum-well structures on silicon
journal, October 2005


Attosecond physics
journal, February 2009


Optical functions of silicon-germanium alloys determined using spectroscopic ellipsometry
journal, April 1993


Carrier-induced change in refractive index of InP, GaAs and InGaAsP
journal, January 1990


Extreme ultraviolet transient absorption of solids from femtosecond to attosecond timescales
journal, January 2016


Probing ultrafast carrier and phonon dynamics in semiconductors
journal, February 1998


Temperature dependence of the direct gap of Si and Ge
journal, April 1983


Attosecond band-gap dynamics in silicon
journal, December 2014


    Works referencing / citing this record:

    Probing ultrafast carrier and phonon dynamics in semiconductors
    journal, February 1998


    Real-Time Probing of Electron Dynamics Using Attosecond Time-Resolved Spectroscopy
    journal, May 2016


    Attosecond Time-Resolved Autoionization of Argon
    journal, October 2010


    Carrier-induced change in refractive index of InP, GaAs and InGaAsP
    journal, January 1990


    Heterogeneous Integration of Compound Semiconductors
    journal, June 2010


    Density-Functional Theory for Time-Dependent Systems
    journal, March 1984


    Ultrafast relaxation dynamics of charge carriers relaxation in ZnO nanocrystalline thin films
    journal, March 2004


    Carrier dynamics in semiconductors studied with time-resolved terahertz spectroscopy
    journal, June 2011


    Attosecond band-gap dynamics in silicon
    journal, December 2014


    Colloidal-quantum-dot photovoltaics using atomic-ligand passivation
    journal, September 2011


    Theory of ultrafast phenomena in photoexcited semiconductors
    journal, August 2002


    Vibrational Spectra of Hydrogen in Silicon and Germanium
    journal, August 1983


    Attosecond physics
    journal, February 2009


    Generalized Gradient Approximation Made Simple
    journal, October 1996


    Optical functions of silicon-germanium alloys determined using spectroscopic ellipsometry
    journal, April 1993


    Non-radiative transitions in semiconductors
    journal, December 1981


    Role of mid-gap states in charge transport and photoconductivity in semiconductor nanocrystal films
    journal, September 2011


    Deposition and Properties of Low-Pressure Chemical-Vapor Deposited Polycrystalline Silicon-Germanium Films
    journal, January 1994


    Direct and simultaneous observation of ultrafast electron and hole dynamics in germanium
    journal, June 2017


    Extreme ultraviolet transient absorption of solids from femtosecond to attosecond timescales
    journal, January 2016


    Statistics of the Recombinations of Holes and Electrons
    journal, September 1952


    Atomic-Scale Perspective of Ultrafast Charge Transfer at a Dye–Semiconductor Interface
    journal, July 2014


    Silicon-based silicon–germanium–tin heterostructure photonics
    journal, March 2014


    Strong quantum-confined Stark effect in germanium quantum-well structures on silicon
    journal, October 2005


    Hydrogenated microcrystalline silicon germanium: A bottom cell material for amorphous silicon‐based tandem solar cells
    journal, December 1996


    Analysis of separable potentials
    journal, October 1991


    Polarization-assisted amplitude gating as a route to tunable, high-contrast attosecond pulses
    journal, January 2016


    Near-band-gap photoluminescence of Si-Ge alloys
    journal, September 1989


    Petahertz optical drive with wide-bandgap semiconductor
    journal, April 2016


    The direct and indirect bandgaps of unstrained Si x Ge 1−x−y Sn y and their photonic device applications
    journal, October 2012


    Core-level shifts of the Ge(100)-(2×1) surface and their origins
    journal, June 1992


    Structural, optical, and spin properties of hydrogenated amorphous silicon‐germanium alloys
    journal, July 1989


    Optical-field-induced current in dielectrics
    journal, December 2012


    Temperature dependence of the direct gap of Si and Ge
    journal, April 1983


    Phonon-Assisted Optical Absorption in Silicon from First Principles
    journal, April 2012


    Lasing in direct-bandgap GeSn alloy grown on Si
    journal, January 2015


    QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials
    journal, September 2009


    Controlling dielectrics with the electric field of light
    journal, December 2012


    Attosecond optical-field-enhanced carrier injection into the GaAs conduction band
    journal, March 2018


    Nonlinear XUV-optical transient grating spectroscopy at the Si L 2,3 –edge
    journal, May 2019


    MBE grown germanium tunnel-junctions—burstein-moss effect and band-edge luminescence in the Ge Zener-Emitter
    journal, November 2017


    Transient absorption spectroscopy using high harmonic generation: a review of ultrafast X-ray dynamics in molecules and solids
    journal, April 2019

    • Geneaux, Romain; Marroux, Hugo J. B.; Guggenmos, Alexander
    • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 377, Issue 2145
    • https://doi.org/10.1098/rsta.2017.0463

    Femtosecond tracking of carrier relaxation in germanium with extreme ultraviolet transient reflectivity
    journal, May 2018


    Retrieval of the complex-valued refractive index of germanium near the M 4,5 absorption edge
    journal, January 2019