Low-energy electro- and photo-emission spectroscopy of GaN materials and devices

Piccardo, Marco; Iveland, Justin; Martinelli, Lucio; Nakamura, Shuji; Choi, Joo Won; Speck, James S.; Weisbuch, Claude; Peretti, Jacques

doi:10.1063/1.4913928

Title: Low-energy electro- and photo-emission spectroscopy of GaN materials and devices

Abstract

We report that in hot-electron semiconductor devices, carrier transport extends over a wide range of conduction states, which often includes multiple satellite valleys. Electrical measurements can hardly give access to the transport processes over such a wide range without resorting to models and simulations. An alternative experimental approach however exists which is based on low-energy electron spectroscopy and provides, in a number of cases, very direct and selective information on hot-electron transport mechanisms. Recent results obtained in GaN crystals and devices by electron emission spectroscopy are discussed. Using near-band-gap photoemission, the energy position of the first satellite valley in wurtzite GaN is directly determined. By electro-emission spectroscopy, we show that the measurement of the electron spectrum emitted from a GaN p-n junction and InGaN/GaN light-emitting diodes (LEDs) under electrical injection of carriers provides a direct observation of transport processes in these devices. In particular, at high injected current density, high-energy features appear in the electro-emission spectrum of the LEDs showing that Auger electrons are being generated in the active region. Finally, these measurements allow us identifying the microscopic mechanism responsible for droop which represents a major hurdle for widespread adoption of solid-state lighting.

Authors:

Piccardo, Marco ^[1]; Iveland, Justin ^[2]; Martinelli, Lucio ^[3]; Nakamura, Shuji ^[2]; Choi, Joo Won ^[4]; Speck, James S. ^[2]; Weisbuch, Claude ^[1]; Peretti, Jacques ^[3]

CNRS-Ecole Polytechnique, Palaiseau (France); Univ. of California, Santa Barbara, CA (United States)
Univ. of California, Santa Barbara, CA (United States)
CNRS-Ecole Polytechnique, Palaiseau (France)
Seoul Viosys Co. Ltd., Won-Si Dong, Danwon-Gu, Ansan City (Korea)

Publication Date:: Mon Mar 16 00:00:00 EDT 2015

Research Org.:: Energy Frontier Research Centers (EFRC) (United States). Center for Energy Efficient Materials (CEEM)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:: 1369764

Grant/Contract Number:: SC0001009

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Applied Physics

Additional Journal Information:: Journal Volume: 117; Journal Issue: 11; Related Information: CEEM partners with the University of California, Santa Barbara (lead); Purdue University; Los Alamos National Laboratory; National Renewable Energy Laboratory; Journal ID: ISSN 0021-8979

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Piccardo, Marco, Iveland, Justin, Martinelli, Lucio, Nakamura, Shuji, Choi, Joo Won, Speck, James S., Weisbuch, Claude, and Peretti, Jacques. Low-energy electro- and photo-emission spectroscopy of GaN materials and devices.  United States: N. p., 2015. 
Web.  doi:10.1063/1.4913928.

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                    Piccardo, Marco, Iveland, Justin, Martinelli, Lucio, Nakamura, Shuji, Choi, Joo Won, Speck, James S., Weisbuch, Claude, & Peretti, Jacques. Low-energy electro- and photo-emission spectroscopy of GaN materials and devices.  United States.  https://doi.org/10.1063/1.4913928

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                    Piccardo, Marco, Iveland, Justin, Martinelli, Lucio, Nakamura, Shuji, Choi, Joo Won, Speck, James S., Weisbuch, Claude, and Peretti, Jacques. Mon .  
"Low-energy electro- and photo-emission spectroscopy of GaN materials and devices".  United States.  https://doi.org/10.1063/1.4913928.  https://www.osti.gov/servlets/purl/1369764.

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@article{osti_1369764,

  title        = {Low-energy electro- and photo-emission spectroscopy of GaN materials and devices},

  author       = {Piccardo, Marco and Iveland, Justin and Martinelli, Lucio and Nakamura, Shuji and Choi, Joo Won and Speck, James S. and Weisbuch, Claude and Peretti, Jacques},

  abstractNote = {We report that in hot-electron semiconductor devices, carrier transport extends over a wide range of conduction states, which often includes multiple satellite valleys. Electrical measurements can hardly give access to the transport processes over such a wide range without resorting to models and simulations. An alternative experimental approach however exists which is based on low-energy electron spectroscopy and provides, in a number of cases, very direct and selective information on hot-electron transport mechanisms. Recent results obtained in GaN crystals and devices by electron emission spectroscopy are discussed. Using near-band-gap photoemission, the energy position of the first satellite valley in wurtzite GaN is directly determined. By electro-emission spectroscopy, we show that the measurement of the electron spectrum emitted from a GaN p-n junction and InGaN/GaN light-emitting diodes (LEDs) under electrical injection of carriers provides a direct observation of transport processes in these devices. In particular, at high injected current density, high-energy features appear in the electro-emission spectrum of the LEDs showing that Auger electrons are being generated in the active region. Finally, these measurements allow us identifying the microscopic mechanism responsible for droop which represents a major hurdle for widespread adoption of solid-state lighting.},

  doi          = {10.1063/1.4913928},

  journal      = {Journal of Applied Physics},

  number       = 11,

  volume       = 117,

  place        = {United States},

  year         = {Mon Mar 16 00:00:00 EDT 2015},

  month        = {Mon Mar 16 00:00:00 EDT 2015}

}

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Title: Low-energy electro- and photo-emission spectroscopy of GaN materials and devices

Abstract

Citation Formats

Identiﬁcation of Auger effect as the dominant mechanism for efficiency droop of LEDs conference, February 2014

Emission of ballistic photoelectrons from p-GaN(Cs,O) with the effective negative electron affinity journal, November 2007

Energy distributions of photoelectrons emitted from p-GaN(Cs, O) with effective negative electron affinity journal, May 2004

Modern theory and applications of photocathodes conference, October 1993

Semiconducting and other major properties of gallium arsenide journal, October 1982

Direct Measurement of Auger Electrons Emitted from a Semiconductor Light-Emitting Diode under Electrical Injection: Identification of the Dominant Mechanism for Efficiency Droop journal, April 2013

Auger recombination rates in nitrides from first principles journal, May 2009

Analysis of processes limiting quantum efficiency of AlGaInN LEDs at high pumping journal, January 2007

Temperature-dependence of the internal efficiency droop in GaN-based diodes journal, October 2011

Determination of the first satellite valley energy in the conduction band of wurtzite GaN by near-band-gap photoemission spectroscopy journal, June 2014

Time-resolved intervalley transitions in GaN single crystals journal, February 2007

White light emitting diodes with super-high luminous efficacy journal, August 2010

Novel photoemission approach to hot-electron transport in semiconductors journal, April 1990

Simple concepts in the measurement of the energy distribution and spin polarization of an electron beam journal, June 1986

Photoemission from activated gallium arsenide. I. Very-high-resolution energy distribution curves journal, March 1985

Experimental Evidence for Optical Population of the X Minima in GaAs journal, April 1967

Auger recombination in InGaN measured by photoluminescence journal, October 2007

High-brightness AlGaInN light-emitting diodes conference, April 2000

InGaN light-emitting diodes: Efficiency-limiting processes at high injection journal, September 2013

Efficiency droop in light-emitting diodes: Challenges and countermeasures: Efficiency droop in light-emitting diodes: Challenges and countermeasures journal, January 2013

Influence of exchange and correlation on structural and electronic properties of AlN, GaN, and InN polytypes journal, November 2011

Origin of electrons emitted into vacuum from InGaN light emitting diodes journal, August 2014

Low-temperature method of cleaning p-GaN(0001) surfaces for photoemitters with effective negative electron affinity journal, October 2004

Band structure nonlocal pseudopotential calculation of the III-nitride wurtzite phase materials system. Part I. Binary compounds GaN, AlN, and InN journal, December 2000

Band bending and photoemission-induced surface photovoltages on clean n - and p -GaN (0001) surfaces journal, September 2002

Optical study of hot electron transport in GaN: Signatures of the hot-phonon effect journal, January 2006

GaAs-Cs: A new type of photoemitter journal, August 1965

Identiﬁcation of Auger effect as the dominant mechanism for efficiency droop of LEDs
conference, February 2014

Emission of ballistic photoelectrons from p-GaN(Cs,O) with the effective negative electron affinity
journal, November 2007

Energy distributions of photoelectrons emitted from p-GaN(Cs, O) with effective negative electron affinity
journal, May 2004

Modern theory and applications of photocathodes
conference, October 1993

Semiconducting and other major properties of gallium arsenide
journal, October 1982

Direct Measurement of Auger Electrons Emitted from a Semiconductor Light-Emitting Diode under Electrical Injection: Identification of the Dominant Mechanism for Efficiency Droop
journal, April 2013

Auger recombination rates in nitrides from first principles
journal, May 2009

Analysis of processes limiting quantum efficiency of AlGaInN LEDs at high pumping
journal, January 2007

Temperature-dependence of the internal efficiency droop in GaN-based diodes
journal, October 2011

Determination of the first satellite valley energy in the conduction band of wurtzite GaN by near-band-gap photoemission spectroscopy
journal, June 2014

Time-resolved intervalley transitions in GaN single crystals
journal, February 2007

White light emitting diodes with super-high luminous efficacy
journal, August 2010

Novel photoemission approach to hot-electron transport in semiconductors
journal, April 1990

Simple concepts in the measurement of the energy distribution and spin polarization of an electron beam
journal, June 1986

Photoemission from activated gallium arsenide. I. Very-high-resolution energy distribution curves
journal, March 1985

Experimental Evidence for Optical Population of the $X$ Minima in GaAs
journal, April 1967

Auger recombination in InGaN measured by photoluminescence
journal, October 2007

High-brightness AlGaInN light-emitting diodes
conference, April 2000

InGaN light-emitting diodes: Efficiency-limiting processes at high injection
journal, September 2013

Efficiency droop in light-emitting diodes: Challenges and countermeasures: Efficiency droop in light-emitting diodes: Challenges and countermeasures
journal, January 2013

Influence of exchange and correlation on structural and electronic properties of AlN, GaN, and InN polytypes
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Origin of electrons emitted into vacuum from InGaN light emitting diodes
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Low-temperature method of cleaning p-GaN(0001) surfaces for photoemitters with effective negative electron affinity
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Band structure nonlocal pseudopotential calculation of the III-nitride wurtzite phase materials system. Part I. Binary compounds GaN, AlN, and InN
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Band bending and photoemission-induced surface photovoltages on clean n - and p -GaN (0001) surfaces
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