Dr. Yongkun Sin Profile

Dr. Yongkun Sin

Senior Scientist at Aerospace Corp

SPIE Involvement:

Author

Publications (42)

Proceedings Article | 13 March 2024 Paper

Reliability and failure mode analysis of high-speed 850-nm multi-mode and 795-nm single-mode VCSELs for space applications

Yongkun Sin, Jesse Theiss, Michael Huang, Emily Tang, Jeffrey Childs, In-Tae Bae, Adam Bushmaker

Proceedings Volume 12904, 129040D (2024) https://doi.org/10.1117/12.3000490

KEYWORDS: Vertical cavity surface emitting lasers, Reliability, Failure analysis, Accelerated life testing, Quantum wells, Photocurrent, Indium gallium arsenide

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Proceedings Article | 12 March 2024 Paper

Time-resolved analysis of degradation in high-power broad-area lasers with quantum well and quantum dot active regions

Yongkun Sin, Cassidy Feltenberger, Dicky Daniel, Matthew Voegtle, In-Tae Bae

Proceedings Volume 12867, 128670I (2024) https://doi.org/10.1117/12.3000500

KEYWORDS: Electroluminescence, Quantum wells, Accelerated life testing, Quantum dots, High power lasers

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Proceedings Article | 15 March 2023 Paper

Reliability and failure mode analysis of high-speed 850nm oxide-confined multi-mode VCSELs for space applications

Yongkun Sin, Jesse Theiss, Michael Huang, Jeffrey Childs, In-Tae Bae, Zachary Lingley

Proceedings Volume 12439, 124390D (2023) https://doi.org/10.1117/12.2647286

KEYWORDS: Vertical cavity surface emitting lasers, Failure analysis, Reliability, Transmission electron microscopy, Quantum wells, Indium gallium arsenide, Accelerated life testing, Satellites

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Proceedings Article | 14 March 2023 Paper

Degradation in high-power broad-area lasers with quantum well and quantum dot active regions: a comparative study

Yongkun Sin, In-Tae Bae, Zachary Lingley

Proceedings Volume 12403, 124030C (2023) https://doi.org/10.1117/12.2647287

KEYWORDS: Transmission electron microscopy, Electroluminescence, Quantum wells, Quantum processes, Quantum dots, High power lasers, Quantum confinement

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Proceedings Article | 5 March 2022 Paper

Physical failure analysis of stressed and proton-irradiated RF AlGaN-GaN HEMTs with Ni-Pd-Au Schottky contacts

Yongkun Sin, Dmitry Veksler, Patrick Edwards, Miles Brodie, Scott Sitzman, Zachary Lingley

Proceedings Volume 12001, 120010E (2022) https://doi.org/10.1117/12.2606276

KEYWORDS: Field effect transistors, Gallium nitride, Transmission electron microscopy, Palladium, Failure analysis, Metals, Gold, Reliability, Nickel, Ion beams

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Proceedings Article | 4 March 2022 Presentation + Paper

Degradation processes in high-power broad-area lasers with strained InGaAs-AlGaAs QW and InAs-GaAs QD active regions

Yongkun Sin, Miles Brodie, Zachary Lingley, Neil Ives

Proceedings Volume 11983, 119830F (2022) https://doi.org/10.1117/12.2606266

KEYWORDS: Quantum wells, Transmission electron microscopy, Electroluminescence, Failure analysis, High power lasers, Laser applications, Quantum dots, Near field, Laser optics, Absorption

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Proceedings Article | 5 March 2021 Presentation + Paper

Reliability and degradation mechanisms in high-power broad-area lasers with strained InGaAs-AlGaAs QW and InAs-GaAs QD active regions

Yongkun Sin, Stephen LaLumondiere, Neil Ives

Proceedings Volume 11668, 116680B (2021) https://doi.org/10.1117/12.2576892

KEYWORDS: Quantum wells, High power lasers, Reliability, Laser applications, Failure analysis, Electroluminescence, Transmission electron microscopy, Telecommunications, Spectroscopy

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Proceedings Article | 5 March 2021 Presentation + Paper

Out-diffusion of Pd as part of degradation mechanisms in RF AlGaN-GaN HEMTs with Ni-Pd-Au Schottky contacts: part II

Yongkun Sin, Dmitry Veksler, William Hubbard, Scott Sitzman, Miles Brodie, Zachary Lingley, Neil Ives

Proceedings Volume 11686, 116862A (2021) https://doi.org/10.1117/12.2576910

KEYWORDS: Field effect transistors, Palladium, Gallium nitride, Transmission electron microscopy, Silicon carbide, Reliability, Strain analysis, Physics, Manufacturing

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Proceedings Article | 2 March 2020 Paper

Physics of failure based reliability model of high-power InGaAs-AlGaAs strained QW lasers prone to COBD failure

Yongkun Sin, Sean Stuart, Miles Brodie, Zachary Lingley

Proceedings Volume 11262, 1126207 (2020) https://doi.org/10.1117/12.2543436

KEYWORDS: Quantum wells, Reliability, Physics, Transmission electron microscopy, High power lasers, Waveguides, Failure analysis, Gallium arsenide, Electroluminescence

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Both broad-area and single-mode strained InGaAs-AlGaAs single quantum well (QW) lasers are indispensable components for both terrestrial and space satellite communications systems due to their excellent power and efficiency characteristics. However, their degradation mode (catastrophic and sudden degradation) due to catastrophic optical damage (COD) is a major concern especially for space applications, since COD-prone lasers typically show no obvious precursor signature of failure. Furthermore, as our group first reported in 2009, these lasers predominantly degrade by a new failure mode (bulk failure) due to catastrophic optical bulk damage (COBD) unlike AlGaAs QW lasers that degrade by a well-known failure mode (facet failure) due to catastrophic optical mirror damage (COMD). Unlike COMD, there have been limited reports on root causes of COBD. In addition, none of decades-long studies of reliability and degradation processes in (Al)GaAs or InGaAs QW lasers by many groups have yielded a reliability model based on the physics of failure. As part of our efforts to develop a physics of failure-based reliability model of InGaAs-AlGaAs strained QW lasers, we continued our investigation by performing short-term and long-term lifetests, failure mode analyses, and root causes investigations using various destructive and non-destructive techniques. All of broad-area and single-mode lasers that we tested degraded by COBD. We employed electron beam induced current (EBIC) techniques to study formation of dark line defects (DLDs) of lasers stressed under different test conditions and time-resolved electroluminescence (TR-EL) techniques to study the dependence of DLD propagation on electrical-thermal stresses via recombination enhanced defect reaction. Also, we employed high-resolution TEM and deep level transient spectroscopy (DLTS) techniques to study extended defects and point defects (and electron traps), respectively. Finally, we report on reliability model parameters obtained from our physics of failure investigation and compare them with those extracted using an empirical model.

Proceedings Article | 27 February 2020 Paper

Out-diffusion of Pd as a potential degradation mechanism in GaN HEMTs with Ni-Pd-Au Schottky contacts

Yongkun Sin, Dmitry Veksler, William Hubbard, Miles Brodie, Scott Sitzman, Zachary Lingley

Proceedings Volume 11280, 112801I (2020) https://doi.org/10.1117/12.2543432

KEYWORDS: Palladium, Field effect transistors, Gallium nitride, Transmission electron microscopy, Nickel, Reliability, Gold, Silicon carbide, Metals

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Proceedings Article | 7 March 2019 Paper

Physics of failure based reliability model of high-power InGaAs-AlGaAs strained QW lasers

Yongkun Sin, Sean Stuart, Stephen LaLumondiere, Miles Brodie, Zachary Lingley

Proceedings Volume 10900, 109000P (2019) https://doi.org/10.1117/12.2507055

KEYWORDS: Quantum wells, Reliability, Failure analysis, Physics, High power lasers, Transmission electron microscopy, Gallium arsenide, Electroluminescence

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Proceedings Article | 1 March 2019 Paper

Electrical and structural characteristics of aged RF GaN HEMTs and irradiated high-power GaN HEMTs with protons and heavy ions

Yongkun Sin, Dmitry Veksler, Jeremy Bonsall, Scott Sitzman, Miles Brodie, Zachary Lingley, Brendan Foran

Proceedings Volume 10918, 109181B (2019) https://doi.org/10.1117/12.2507016

KEYWORDS: Field effect transistors, Gallium nitride, Transmission electron microscopy, Reliability, Strain analysis, Radiation effects, Amplifiers

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Proceedings Article | 14 March 2018 Paper

Root causes investigation of catastrophic optical bulk damage in high-power InGaAs-AlGaAs strained QW lasers

Yongkun Sin, Zachary Lingley, Talin Ayvazian, Miles Brodie, Neil Ives

Proceedings Volume 10553, 105531E (2018) https://doi.org/10.1117/12.2287288

KEYWORDS: Quantum wells, Failure analysis, Reliability, High power lasers, Transmission electron microscopy, Electroluminescence, Satellite communications, Telecommunications, Satellites, Electron beams

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High-power single-mode (SM) and multi-mode (MM) InGaAs-AlGaAs strained quantum well (QW) lasers are critical components for both terrestrial and space satellite communications systems. Since these lasers predominantly fail by catastrophic and sudden degradation due to COD, it is especially crucial for space satellite applications to investigate reliability, failure modes, and degradation mechanisms of these lasers. Our group reported a new failure mode in MM and SM InGaAs-AlGaAs strained QW lasers in 2009 and 2016, respectively. Our group also reported in 2017 that bulk failure due to catastrophic optical bulk damage (COBD) is the dominant failure mode of both SM and MM lasers that were subject to long-term life-tests. For the present study, we report root causes investigation of COBD by performing long-term lifetests followed by failure mode analysis (FMA) using various micro-analytical techniques including electron beam induced current (EBIC), time-resolved electroluminescence (EL), focused ion beam (FIB), high-resolution transmission electron microscopy (TEM), and deep level transient spectroscopy (DLTS). Our life-tests with accumulated test hours of over 25,000 hours for SM lasers and over 35,000 hours for MM lasers generated a number of COBD failures with various failure times. EBIC techniques were employed to study dark line defects (DLDs) generated in SM COBD failures stressed under different test conditions. FIB and high-resolution TEM were employed to prepare cross sectional and plan view TEM specimens to study DLD areas (dislocations) in post-aged SM lasers. Time-resolved EL techniques were employed to study initiation and progressions of dark spots and dark lines in real time as MM lasers were aged. Lastly, to investigate precursor signatures of failure and degradation mechanisms responsible for COBD in both SM and MM lasers, we employed DLTS techniques to study a role that electron traps (non-radiative recombination centers) play in degradation of these lasers. Our in-depth root causes investigation results are reported.

Proceedings Article | 6 March 2018 Paper

Catastrophic optical bulk degradation in high-power single- and multi-mode InGaAs-AlGaAs strained QW lasers: part II

Yongkun Sin, Talin Ayvazian, Miles Brodie, Zachary Lingley

Proceedings Volume 10514, 1051414 (2018) https://doi.org/10.1117/12.2286776

KEYWORDS: Failure analysis, Quantum wells, Transmission electron microscopy, Reliability, Scanning transmission electron microscopy, High power lasers

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Proceedings Article | 22 February 2017 Paper

Catastrophic optical bulk degradation (COBD) in high-power single- and multi-mode InGaAs-AlGaAs strained quantum well lasers

Yongkun Sin, Zachary Lingley, Miles Brodie, Nathan Presser, Steven Moss

Proceedings Volume 10086, 100860S (2017) https://doi.org/10.1117/12.2250253

KEYWORDS: High power lasers, Quantum wells, Reliability, Failure analysis, Transmission electron microscopy, Satellite communications, Telecommunications, Nondestructive evaluation, Scanning transmission electron microscopy, Waveguides, Electroluminescence, Laser development

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Proceedings Article | 16 February 2017 Paper

Electrical characteristics of high-power AlGaN-GaN high electron mobility transistors irradiated with protons and heavy ions

Yongkun Sin, Jeremy Bonsall, Zachary Lingley, Miles Brodie, Maribeth Mason

Proceedings Volume 10104, 101041B (2017) https://doi.org/10.1117/12.2250250

KEYWORDS: Field effect transistors, Gallium nitride, Transmission electron microscopy, Reliability, Radiation effects, Transistors, Solid state electronics, Amplifiers, Silicon carbide, Diodes

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Proceedings Article | 14 March 2016 Paper

Carrier dynamics in QW and bulk bismide and epitaxial lift off GaAs-In(Al)GaP double heterostructures grown by MOVPE for multi-junction solar cells

Yongkun Sin, Mark Peterson, Zachary Lingley, Stephen LaLumondiere, Steven Moss, Honghyuk Kim, Kamran Forghani, Yingxin Guan, Kangho Kim, Jaejin Lee, Luke Mawst, Thomas Kuech, Rao Tatavarti

Proceedings Volume 9743, 974313 (2016) https://doi.org/10.1117/12.2208804

KEYWORDS: Carrier dynamics, Quantum wells, Indium gallium phosphide, Multijunction solar cells, Heterojunctions, Gallium arsenide, Annealing, Epitaxial lateral overgrowth, Luminescence, Bismuth, Solar cells, Tellurium, Ions, Transmission electron microscopy

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III-V multi-junction solar cells are based on a triple-junction design that consists of an InGaP top junction, a GaAs middle junction, and a bottom junction that employs either a 1eV material grown on the GaAs substrate or InGaAs grown on the Ge substrate. The most promising 1 eV materials under extensive investigation are the bulk dilute nitride such as InGaAsN(Sb) lattice-matched to GaAs substrate and the dilute-bismide quantum well materials, such as GaAsBi, strain-compensated with GaAsP barriers. Both approaches have the potential to achieve high performance triple-junction solar cells. In addition, space satellite applications utilizing III-V triple-junction solar cells can have significantly reduced weight and high efficiency. An attractive approach to achieve these goals is to employ full-wafer epitaxial lift off (ELO) technology, which can eliminate the substrate weight and also enable multiple substrate re-usages. For the present study, we employed time-resolved photoluminescence (TR-PL) techniques to study carrier dynamics in MOVPE-grown bulk dilute bismide double heterostructures (DH). Carrier lifetime measurements are crucial to optimizing MOVPE materials growth. We have studied carrier dynamics in GaAsBi QW structures with GaAsP barriers. Carrier lifetimes were measured from GaAsBi DH samples at different stages of post-growth thermal annealing steps. Post-growth annealing yielded significant improvements in carrier lifetimes. Based on this study, single junction solar cells (SJSC) were grown and annealed under a variety of conditions and characterized. The SJSC annealed at 600 – 650 °C exhibited improved response in EQE spectra. In addition, we studied carrier dynamics in MOVPE-grown GaAs-In(Al)GaP DH samples grown on GaAs substrates. The structures were grown on top of a thin AlAs release layer, which allowed epitaxial layers grown on top of the AlAs layer to be removed from the substrate. The GaAs active layers had various doping densities and thicknesses. Our TR-PL results from both pre- and post-ELO processed GaAs-In(Al)GaP DH samples are reported.

Proceedings Article | 4 March 2016 Paper

Reliability, failure modes, and degradation mechanisms in high power single- and multi-mode InGaAs-AlGaAs strained quantum well lasers

Yongkun Sin, Nathan Presser, Zachary Lingley, Miles Brodie, Brendan Foran, Steven Moss

Proceedings Volume 9733, 973304 (2016) https://doi.org/10.1117/12.2208802

KEYWORDS: Transmission electron microscopy, Bulk lasers

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Proceedings Article | 4 March 2016 Paper

Failure mode analysis of degraded InGaAs-AlGaAs strained quantum well multi-mode vertical-cavity surface-emitting lasers

Yongkun Sin, Zachary Lingley, Miles Brodie, Michael Huang, Adam Bushmaker, Jesse Theiss, Nathan Presser, Brendan Foran, Steven Moss

Proceedings Volume 9766, 97660F (2016) https://doi.org/10.1117/12.2208799

KEYWORDS: Vertical cavity surface emitting lasers, Failure analysis, Reliability, Indium gallium arsenide, Nondestructive evaluation, Transmission electron microscopy, Satellite communications, Quantum wells, Electroluminescence, Ions, Oxides, Mirrors, Virtual colonoscopy

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Proceedings Article | 16 March 2015 Paper

Time-resolved PL and TEM studies of MOVPE-grown bulk dilute nitride and bismide quantum well heterostructure

Yongkun Sin, Zachary Lingley, Mark Peterson, Miles Brodie, Steven Moss, Tae Wan Kim, Honghyuk Kim, Yingxin Guan, Kamran Forghani, Luke Mawst, Thomas Kuech

Proceedings Volume 9358, 93580I (2015) https://doi.org/10.1117/12.2076785

KEYWORDS: Transmission electron microscopy, Quantum wells, Gallium arsenide, Carrier dynamics, Heterojunctions, Temperature metrology, Annealing, Solar cells, Statistical analysis, Bismuth

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Proceedings Article | 13 March 2015 Paper

Degradation mechanisms in high-power multi-mode InGaAs-AlGaAs strained quantum well lasers for high-reliability applications

Yongkun Sin, Nathan Presser, Miles Brodie, Zachary Lingley, Brendan Foran, Steven Moss

Proceedings Volume 9348, 93480L (2015) https://doi.org/10.1117/12.2076788

KEYWORDS: Semiconductor lasers, Quantum wells, Reliability, Physics, Laser applications, Transmission electron microscopy, Systems modeling, Performance modeling, Electroluminescence, Arsenic

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Laser diode manufacturers perform accelerated multi-cell lifetests to estimate lifetimes of lasers using an empirical model. Since state-of-the-art laser diodes typically require a long period of latency before they degrade, significant amount of stress is applied to the lasers to generate failures in relatively short test durations. A drawback of this approach is the lack of mean-time-to-failure data under intermediate and low stress conditions, leading to uncertainty in model parameters (especially optical power and current exponent) and potential overestimation of lifetimes at usage conditions. This approach is a concern especially for satellite communication systems where high reliability is required of lasers for long-term duration in the space environment. A number of groups have studied reliability and degradation processes in GaAs-based lasers, but none of these studies have yielded a reliability model based on the physics of failure. The lack of such a model is also a concern for space applications where complete understanding of degradation mechanisms is necessary. Our present study addresses the aforementioned issues by performing long-term lifetests under low stress conditions followed by failure mode analysis (FMA) and physics of failure investigation. We performed low-stress lifetests on both MBE- and MOCVD-grown broad-area InGaAs- AlGaAs strained QW lasers under ACC (automatic current control) mode to study low-stress degradation mechanisms. Our lifetests have accumulated over 36,000 test hours and FMA is performed on failures using our angle polishing technique followed by EL. This technique allows us to identify failure types by observing dark line defects through a window introduced in backside metal contacts. We also investigated degradation mechanisms in MOCVD-grown broad-area InGaAs-AlGaAs strained QW lasers using various FMA techniques. Since it is a challenge to control defect densities during the growth of laser structures, we chose to control defect densities by introducing extrinsic point defects to the laser via proton irradiation with different energies and fluences. These lasers were subsequently lifetested to study degradation processes in the lasers with different defect densities and also to study precursor signatures of failures - traps and non-radiative recombination centers (NRCs) in pre- and post-stressed lasers. Lastly, we employed focused ion beam (FIB), electron beam induced current (EBIC), and highresolution TEM (HR-TEM) techniques to further study dark line defects and dislocations in both post-aged and postproton irradiated lasers. We report on our long-term low-stress lifetest results and physics of failure investigation results.

Proceedings Article | 10 March 2015 Paper

Destructive physical analysis of degraded quantum cascade lasers

Y. Sin, Z. Lingley, M. Brodie, N. Presser, S. Moss, J. Kirch, C. C. Chang, C. Boyle, L. Mawst, D. Botez, D. Lindberg, Thomas Earles

Proceedings Volume 9382, 93821P (2015) https://doi.org/10.1117/12.2076641

KEYWORDS: Quantum cascade lasers, Transmission electron microscopy, Quantum wells, Failure analysis, Scanning electron microscopy, Chemical analysis, Waveguides, Laser damage threshold, Remote sensing, Reliability

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Remarkable progress made in quantum cascade lasers (QCLs) has led them to find an increasing number of applications in remote sensing, chemical sensing, and free space communications, in addition to potential space applications. However, little has been reported on reliability and failure modes of QCLs although it is crucial to understand failure modes and underlying degradation mechanisms in developing QCLs that meet lifetime requirements for space missions. Focused ion beam (FIB) techniques have been employed to investigate failure modes in various types of laser diodes. Our group has also used FIB to study failure modes in single-mode and multi-mode InGaAs-AlGaAs strained QW lasers, but few groups have used this technique to investigate failure modes in QCLs. In our study, we report on destructive physical analysis (DPA) of degraded InGaAs-InAlAs QCLs using FIB and high-resolution TEM techniques. The active region of QCLs that we studied consisted of two-23 stage layers of InGaAs-InAlAs separated by a 0.5 μm thick InP spacer layer for 8.4μm QCLs and 30-stage layers of lattice-matched InGaAs-InAlAs heterostructure for 4.7μm QCLs. The MOVPE-grown laser structures were fabricated into deep-etched ridge waveguide QCLs. L-I-V-spectral characteristics were measured at RT under pulsed operation. Our 8.4μm QCLs with as-cleaved and HR-coated facets showed a laser threshold of 1.7 A and a threshold voltage of 13 V at RT, whereas our 4.7μm QCLs without facet coating showed threshold currents of 320 - 400 mA and threshold voltages of 13 - 13.5V. Failures were generated via short-term tests of QCLs. FIB systems were used to study the damage area on the front facet and also to prepare TEM cross sections at different locations along the waveguide for defect and chemical analyses using a HR-TEM. In contrast to the COMD damaged area showing as a blister on the front facet of QW lasers, the damaged area of QCLs was significantly extended into the InP substrate due to a much less absorption of lasing photons in QCLs. Our detailed destructive physical analysis results are reported including defect, structural, and chemical analysis results from degraded QCLs.

Proceedings Article | 8 March 2014 Paper

Electrical characteristics of AlGaN-GaN high electron mobility transistors and AlGaN Schottky diodes irradiated with protons

Yongkun Sin, Nathan Presser, Brendan Foran, Stephen LaLumondiere, William Lotshaw, Steven Moss

Proceedings Volume 8986, 89861E (2014) https://doi.org/10.1117/12.2037637

KEYWORDS: Field effect transistors, Diodes, Gallium nitride, Gallium arsenide, Silicon carbide, Reliability, Transmission electron microscopy, Transistors, Semiconducting wafers, Aluminum nitride

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AlGaN-GaN high electron mobility transistors (HEMTs) are most suitable for commercial and military applications requiring high voltage, high power, and high efficiency operation. In recent years, leading AlGaN HEMT manufacturers have reported encouraging reliability of these devices, but their long-term reliability especially in the space environment still remains a major concern. In addition, degradation mechanisms in AlGaN HEMT devices are still not well understood, and a large number of traps and defects present both in the bulk and at the surface lead to undesirable characteristics. Study of reliability and radiation effects of AlGaN-GaN HEMTs is therefore necessary before GaN HEMT technology is successfully employed in satellite communication systems. For the present study, we investigated electrical characteristics of AlGaN-GaN HEMTs and AlGaN Schottky diodes irradiated with protons. We studied two types of MOCVD-grown AlGaN HEMTs on semi-insulating SiC substrates (HEMT-1 and HEMT-2) as well as MOCVD-grown Al_0.27Ga_0.73N Schottky diodes on conducting SiC substrates. Our HEMT-1 structure consisted of a GaN cap, AlGaN/AlN barrier, and 2 μm GaN buffer layers. Our HEMT-2 structure consisting of undoped AlGaN barrier and GaN buffer layers grown on an AlN nucleation layer showed a charge sheet density of ~10¹³/cm² and a Hall mobility of ~1500 cm² /V^.sec. Our HEMT-1 devices had a Pt-Au Schottky gate length of 0.2 μm, a total gate width of 200-400 μm periphery, and SiN_x passivation. Electrical characteristics of AlGaN-GaN HEMTs and AlGaN Schottky diodes were compared before and after they were proton irradiated with different energies and fluences. Current-mode deep level transient spectroscopy (DLTS) and capacitance-mode DLTS were employed to study pre-proton irradiation trap characteristics in the AlGaN-GaN HEMTs and AlGaN Schottky diodes, respectively. Focused ion beam (FIB) was employed to prepare both cross-sectional and plan view TEM samples for defect analysis using a high resolution TEM. In addition, electrical characteristics of GaAs MESFETs used as reference devices were compared before and after they were proton irradiated.

Proceedings Article | 7 March 2014 Paper

Variable temperature carrier dynamics in bulk (In)GaAsNSb materials grown by MOVPE for multi-junction solar cells

Yongkun Sin, Zachary Lingley, Stephen LaLumondiere, Nathan Wells, William Lotshaw, Steven Moss, Tae Wan Kim, Luke Mawst, Thomas Kuech

Proceedings Volume 8981, 89811A (2014) https://doi.org/10.1117/12.2037385

KEYWORDS: Gallium arsenide, Carrier dynamics, Temperature metrology, Multijunction solar cells, Transmission electron microscopy, Annealing, Indium gallium phosphide, Antimony, Germanium, Picosecond phenomena

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Proceedings Article | 7 March 2014 Paper

Catastrophic degradation in high power multi-mode InGaAs-AlGaAs strained quantum well lasers with intrinsic and irradiation-induced defects

Yongkun Sin, Stephen LaLumondiere, Erica DeIonno, Brendan Foran, Nathan Presser, William Lotshaw, Steven Moss

Proceedings Volume 8965, 896504 (2014) https://doi.org/10.1117/12.2037642

KEYWORDS: Semiconductor lasers, Quantum wells, Transmission electron microscopy, Reliability, Failure analysis, High power lasers, Gallium arsenide, Electroluminescence, Physics, Scanning transmission electron microscopy

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A number of groups have studied reliability and degradation processes in GaAs-based lasers, but none of these studies have yielded a reliability model based on the physics of failure. Unsuccessful development of this model originates from the facts that: (i) defects related phenomena responsible for degradation in GaAs-based lasers are difficult to study due to the lack of suitable non-destructive techniques and (ii) degradation process occurs extremely fast after a long period of latency. Therefore, most of laser diode manufacturers perform accelerated multi-cell lifetests to estimate lifetimes of lasers using an empirical model, but this approach is a concern especially for satellite communication systems where high reliability is required of lasers for long-term duration in the space environment. Since it is a challenge to control defects introduced during the growth of laser structures, we studied degradation processes in broad-area InGaAs-AlGaAs strained quantum well (QW) lasers with intrinsic defects as well as those with defects introduced via proton irradiation. For the present study, we investigated the root causes of catastrophic degradation processes in MOCVD-grown broad-area InGaAs-AlGaAs strained QW lasers using various failure mode analysis techniques. A number of lasers were proton irradiated with different energies and fluences. We also studied GaAs double heterostructure (DH) test samples with different amounts of intrinsic defects introduced during MOCVD growth. These samples were proton irradiated as well to introduce additional defects. Deep level transient spectroscopy (DLTS) and time resolved photoluminescence (TR-PL) techniques were employed to study traps (due to point defects) and non-radiative recombination centers (NRCs) in pre- and poststressed lasers, respectively. These characteristics were compared with those in pre- and post-proton irradiated lasers and DHs to study the role that defects and NRCs play in catastrophic degradation processes. Lastly, we employed focused ion beam (FIB), electron beam induced current (EBIC), and high resolution TEM (HR-TEM) techniques to study dark line defects and crystal defects in both post-aged and post-proton irradiated lasers.

Proceedings Article | 25 March 2013 Paper

Carrier dynamics in bulk 1eV InGaAsNSb materials and epitaxial lift off GaAs-InAlGaP layers grown by MOVPE for multi-junction solar cells

Yongkun Sin, Stephen LaLumondiere, William Lotshaw, Steven Moss, Tae Wan Kim, Kamran Forghani, Luke Mawst, Thomas Kuech, Rao Tatavarti, Andree Wibowo, Noren Pan

Proceedings Volume 8620, 86201L (2013) https://doi.org/10.1117/12.2001528

KEYWORDS: Epitaxial lateral overgrowth, Gallium arsenide, Carrier dynamics, Picosecond phenomena, Antimony, Multijunction solar cells, Solar cells, Zinc, Electroluminescence, Annealing

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III-V multi-junction solar cells are based on a triple-junction design that consists of an InGaP top junction, a GaAs middle junction, and a bottom junction that employs either a 1eV material grown on the GaAs substrate or InGaAs grown on the Ge substrate. The most promising 1 eV material that is currently under extensive investigation is bulk dilute nitride such as InGaAsN(Sb) lattice matched to GaAs substrates. Both approaches utilizing dilute nitrides and lattice-mismatched InGaAs layers have a potential to achieve high performance triple-junction solar cells. In addition, it will be beneficial for both commercial and space applications if III-V triple-junction solar cells can significantly reduce weight and can be manufactured cost effectively while maintaining high efficiency. The most attractive approach to achieve these goals is to employ full-wafer epitaxial lift off (ELO) technology, which can eliminate the substrate weight and also enable multiple substrate re-usages. For the present study, we employed time-resolved photoluminescence (TR-PL) techniques to study carrier dynamics in MOVPE-grown bulk dilute nitride layers lattice matched to GaAs substrates, where carrier lifetime measurements are crucial in optimizing MOVPE materials growth. We studied carrier dynamics in InGaAsN(Sb) layers with different amounts of N incorporated. Carrier lifetimes were also measured from InGaAsN(Sb) layers at different stages of post-growth thermal annealing steps. Post-growth annealing yielded significant improvements in carrier lifetimes of InGaAsNSb double hetero-structure (DH) samples compared to InGaAsN DH samples possibly due to the surfactant effect of Sb. In addition, we studied carrier dynamics in MOVPE-grown GaAs-InAl(Ga)P layers grown on GaAs substrates. The structures were grown on top of a thin AlAs release layer, which allowed epitaxial layers grown on top of the AlAs layer to be removed from the substrate. The GaAs layers had various doping densities and thicknesses. We present our TR-PL results from both pre- and post-ELO processed GaAs-InAl(Ga)P samples.

Proceedings Article | 4 March 2013 Paper

Catastrophic degradation in high-power InGaAs-AlGaAs strained quantum well lasers and InAs-GaAs quantum dot lasers

Yongkun Sin, Stephen LaLumondiere, Brendan Foran, Neil Ives, Nathan Presser, William Lotshaw, Steven Moss

Proceedings Volume 8640, 86401G (2013) https://doi.org/10.1117/12.2006624

KEYWORDS: Quantum wells, Semiconductor lasers, Laser applications, High power lasers, Fiber lasers, Reliability, Transmission electron microscopy, Astatine, Electroluminescence, Indium gallium arsenide

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Proceedings Article | 4 March 2013 Paper

Traps and defects in pre- and post-proton irradiated AlGaN-GaN high electron mobility transistors and AlGaN Schottky diodes

Yongkun Sin, Brendan Foran, Nathan Presser, Stephen LaLumondiere, William Lotshaw, Steven Moss

Proceedings Volume 8625, 86250Z (2013) https://doi.org/10.1117/12.2001526

KEYWORDS: Field effect transistors, Diodes, Gallium nitride, Reliability, Silicon carbide, Transmission electron microscopy, Neodymium, Transistors, Semiconducting wafers, Aluminum nitride

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Proceedings Article | 26 February 2013 Paper

Catastrophic optical bulk damage (COBD) processes in aged and proton-irradiated high power InGaAs-AlGaAs strained quantum well lasers

Yongkun Sin, Stephen LaLumondiere, Brendan Foran, William Lotshaw, Steven Moss

Proceedings Volume 8605, 86050M (2013) https://doi.org/10.1117/12.2001530

KEYWORDS: Quantum wells, Reliability, Semiconductor lasers, Lab on a chip, High power lasers, Electroluminescence, Laser applications, Laser optics, Failure analysis, Transmission electron microscopy

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Proceedings Article | 28 February 2012 Paper

Carrier dynamics and defects in MOVPE-grown bulk InGaAs layers with metamorphic InGaAs and InGaPSb buffer layers for solar cells

Yongkun Sin, Stephen LaLumondiere, Brendan Foran, William Lotshaw, Steven Moss, Tae Wan Kim, Peter Dudley, Jeremy Kirch, Steven Ruder, Luke Mawst, Thomas Kuech

Proceedings Volume 8255, 825516 (2012) https://doi.org/10.1117/12.906424

KEYWORDS: Indium gallium arsenide, Chemical mechanical planarization, Gallium arsenide, Transmission electron microscopy, Surface roughness, Carrier dynamics, Solar cells, Indium gallium phosphide, Luminescence, Antimony

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Proceedings Article | 22 February 2012 Paper

Characteristics of bulk InGaAsN and InGaAsSbN materials grown by metal organic vapor phase epitaxy (MOVPE) for solar cell application

TaeWan Kim, Toby Garrod, Kangho Kim, Jaejin Lee, Luke Mawst, T. Kuech, S. LaLumondiere, Y. Sin, W. Lotshaw, S. Moss

Proceedings Volume 8256, 82561D (2012) https://doi.org/10.1117/12.906961

KEYWORDS: Solar cells, Carbon, Gallium arsenide, Picosecond phenomena, Metals, Annealing, Antimony, External quantum efficiency, Vapor phase epitaxy, Antireflective coatings

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Proceedings Article | 9 February 2012 Paper

Physics of failure investigation in high-power broad-area InGaAs-AlGaAs strained quantum well lasers

Yongkun Sin, Stephen LaLumondiere, Nathan Presser, Brendan Foran, Neil Ives, William Lotshaw, Steven Moss

Proceedings Volume 8241, 824116 (2012) https://doi.org/10.1117/12.906436

KEYWORDS: Quantum wells, Semiconductor lasers, High power lasers, Transmission electron microscopy, Refractive index, Physics, Laser optics, Failure analysis, Reliability, Absorption

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Proceedings Article | 21 February 2011 Paper

Carrier dynamics in MOVPE-grown bulk dilute nitride materials for multi-junction solar cells

Yongkun Sin, Stephen LaLumondiere, Toby Garrod, Tae Wan Kim, Jeremy Kirch, Luke Mawst, William Lotshaw, Steven Moss

Proceedings Volume 7933, 79330H (2011) https://doi.org/10.1117/12.873894

KEYWORDS: Picosecond phenomena, Annealing, Antimony, Gallium arsenide, Carrier dynamics, Carbon, Multijunction solar cells, Doping, Streak cameras, Diffusion

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Proceedings Article | 17 February 2011 Paper

Nanopatterned quantum dot active region lasers on InP substrates

L. Mawst, J. H. Park, Y. Huang, J. Kirch, Y. Sin, B. Foran, C.-C. Liu, P. Nealey, T. Kuech

Proceedings Volume 7953, 795304 (2011) https://doi.org/10.1117/12.875199

KEYWORDS: Nanostructures, Indium arsenide, Indium gallium arsenide, Quantum dots, Electroluminescence, Metalorganic chemical vapor deposition, Scanning electron microscopy, Dielectrics, Photomasks, Semiconductor lasers

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Proceedings Article | 11 February 2011 Paper

Catastrophic optical bulk damage (COBD) in high power multi-mode InGaAs-AlGaAs strained quantum well lasers

Yongkun Sin, Neil Ives, Stephen LaLumondiere, Nathan Presser, Steven Moss

Proceedings Volume 7918, 791803 (2011) https://doi.org/10.1117/12.873936

KEYWORDS: Quantum wells, Semiconductor lasers, Indium gallium arsenide, Failure analysis, Absorption, Electroluminescence, High power lasers, Laser development, Laser optics, Performance modeling

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Proceedings Article | 18 February 2010 Paper

Root cause investigation of catastrophic degradation in high power multi-mode InGaAs-AlGaAs strained quantum well lasers

Yongkun Sin, Neil Ives, Nathan Presser, Steven Moss

Proceedings Volume 7583, 758307 (2010) https://doi.org/10.1117/12.840708

KEYWORDS: Quantum wells, Absorption, Semiconductor lasers, Electroluminescence, Failure analysis, High power lasers, Laser applications, Reliability, Interfaces, Thermography

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Proceedings Article | 24 February 2009 Paper

Catastrophic facet and bulk degradation in high power multi-mode InGaAs strained quantum well single emitters

Yongkun Sin, Nathan Presser, Brendan Foran, Neil Ives, Steven Moss

Proceedings Volume 7198, 719818 (2009) https://doi.org/10.1117/12.807359

KEYWORDS: Failure analysis, Semiconductor lasers, Quantum wells, Transmission electron microscopy, Indium gallium arsenide, Reliability, Laser applications, Statistical analysis, Scanning electron microscopy, Ion beams

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Proceedings Article | 3 February 2009 Paper

Degradation processes in high power multi-mode InGaAs strained quantum well lasers

Yongkun Sin, Nathan Presser, Brendan Foran, Steven Moss

Proceedings Volume 7230, 72300Y (2009) https://doi.org/10.1117/12.814661

KEYWORDS: Transmission electron microscopy, Quantum wells, Failure analysis, Reliability, Semiconductor lasers, Indium gallium arsenide, Ion beams, Electrical breakdown, Scanning transmission electron microscopy, High power lasers

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Recently, broad-area InGaAs-AlGaAs strained quantum well (QW) lasers have attracted much attention because of their unparalleled high optical output power characteristics that narrow stripe lasers or tapered lasers can not achieve. However, broad-area lasers suffer from poor beam quality and their high reliability operation has not been proven for communications applications. This paper concerns reliability and degradation aspects of broad-area lasers. Good facet passivation techniques along with optimized structural designs have led to successful demonstration of reliable 980nm single-mode lasers, and the dominant failure mode of both single-mode and broadarea lasers is catastrophic optical mirror damage (COMD), which limits maximum output powers and also determines operating output powers. Although broad-area lasers have shown characteristics unseen from singlemode lasers including filamentation, their effects on long-term reliability and degradation processes have not been fully investigated. Filamentation can lead to instantaneous increase in optical power density and thus temperature rise at localized areas through spatial-hole burning and thermal lensing which significantly reduces filament sizes under high power operation, enhancing the COMD process. We investigated degradation processes in commercial MOCVD-grown broad-area InGaAs-AlGaAs strained QW lasers at ~975nm with and without passivation layers by performing accelerated lifetests of these devices followed by failure mode analyses with various micro-analytical techniques. Since instantaneous fluctuations of filaments can lead to faster wear-out of passivation layer thus leading to facet degradation, both passivated and unpassivated broad-area lasers were studied that yielded catastrophic failures at the front facet and also in the bulk. Electron beam induced current technique was employed to study dark line defects (DLDs) generated in degraded lasers stressed under different test conditions and focused ion beam was employed to prepare TEM samples from the DLD areas for HR-TEM analysis. We report our in-depth failure mode analysis results.

Proceedings Article | 13 February 2008 Paper

Investigation of catastrophic degradation in high power multimode InGaAs strained quantum well single emitters

Yongkun Sin, Nathan Presser, Brendan Foran, Steven Moss

Proceedings Volume 6876, 68760R (2008) https://doi.org/10.1117/12.761848

KEYWORDS: Semiconductor lasers, Quantum wells, Transmission electron microscopy, Indium gallium arsenide, Failure analysis, Ion beams, High power lasers, Laser applications, Reliability, Waveguides

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Proceedings Article | 7 February 2007 Paper

Reliability and failure mode investigation of high-power multimode InGaAs strained quantum well single emitters

Yongkun Sin, Brendan Foran, Nathan Presser, Maribeth Mason, Steven Moss

Proceedings Volume 6456, 645605 (2007) https://doi.org/10.1117/12.697194

KEYWORDS: Semiconductor lasers, Reliability, Quantum wells, Failure analysis, Measurement devices, Resistance, Indium gallium arsenide, Scanning electron microscopy, Temperature metrology, Statistical analysis

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Proceedings Article | 15 February 2006 Paper

Characteristics and reliability of high power multi-mode InGaAs strained quantum well single emitters with CW output powers of over 5-W

Yongkun Sin, Nathan Presser, Maribeth Mason, Steven Moss

Proceedings Volume 6104, 61040H (2006) https://doi.org/10.1117/12.673237

KEYWORDS: Temperature metrology, Reliability, Quantum wells, Measurement devices, Semiconductor lasers, Resistance, Laser applications, High power lasers, Indium gallium arsenide, Continuous wave operation

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Proceedings Article | 1 April 2005 Paper

Novel tunable DFB lasers with FIB-deposited heaters

Yongkun Sin, Nathan Presser, Maribeth Mason

Proceedings Volume 5738, (2005) https://doi.org/10.1117/12.589430

KEYWORDS: Platinum, Tunable lasers, Gold, Thin films, Ion beams, Semiconductor lasers, Electronics, Control systems, Resistance, Quantum cascade lasers

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Showing 5 of 42 publications

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