S. Ringel

S. Denbaars, S. Ringel, U. Mishra, 2003, 2003 International Symposium on Compound Semiconductors: Post-Conference Proceedings (IEEE Cat. No.03TH8767).

Deep levels in n-type Schottky and p+-n homojunction GaN diodes

S. Denbaars, S. Ringel, U. Mishra, 2000 .

Deep Levels in n-Type Schottky and p + -n Homojunction GaN Diodes

S. Denbaars, S. Ringel, U. Mishra, 1999 .

Investigation of traps density and position in alkali treated Cu(In,Ga)Se2 thin films and solar cells

A. Rockett, S. Ringel, P. Paul, 2017 .

Investigation of polycrystalline CdZnTe, CdMnTe, and CdTe films for photovoltaic applications

S. Ringel, A. Rohatgi, P. Meyers, 1989 .

Impact of the Ga/In ratio on defects in Cu(In, Ga)Se2

S. Ringel, P. Paul, S. Marsillac, 2016, 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC).

Role of Al content on surface structure evolution of low temperature AlxGa1−xAs and its effect on critical thickness

S. Ringel, J. Carlin, R. Sacks, 1998 .

Impact of Surface Treatment on Interface States of ALD Al2O3/GaN Interfaces

S. Ringel, J. Speck, T. Grassman, 2017 .

Spontaneous compositional superlattice and band-gap reduction in Si-doped AlxGa1−xN epilayers

W. Schaff, S. Ringel, L. Brillson, 2005 .

Compositional modulation and optical emission in AlGaN epitaxial films

Yu Cao, W. Schaff, D. Jena, 2006 .

Effect of threading dislocation density on Ni∕n-GaN Schottky diode I-V characteristics

S. Denbaars, S. Ringel, U. Mishra, 2006 .

Electron trapping kinetics at dislocations in relaxed Ge0.3Si0.7/Si heterostructures

E. Fitzgerald, Yahong Xie, S. Ringel, 1995 .

Analysis of short- and long-term performance goals for III/V on active Si concentrator solar cells

D. Aiken, S. Ringel, J. Carlin, 2013, 2013 IEEE 39th Photovoltaic Specialists Conference (PVSC).

Non-linear behaviors of dark current slope in P+N GaAs solar cells following proton irradiations

H. Barnaby, S. Messenger, R. Walters, 2009, 2009 34th IEEE Photovoltaic Specialists Conference (PVSC).

Investigation of Rear-Emitter GaAs0.75P0.25 Top Cells for Application to III–V/Si Tandem Photovoltaics

S. Ringel, T. Grassman, Daniel L. Lepkowski, 2019, IEEE Journal of Photovoltaics.

Characterization of traps in InAlN by optically and thermally stimulated deep level defect spectroscopies

S. Ringel, J. Speck, E. Farzana, 2018, Journal of Applied Physics.

Deep level traps in semi‐polar n‐GaN grown on patterned sapphire substrate by metalorganic vapor phase epitaxy

E. Fitzgerald, S. Ringel, P. Vennégués, 2016 .

Detailed characterization of deep level defects in InGaN Schottky diodes by optical and thermal deep level spectroscopies

S. Ringel, S. Rajan, S. Krishnamoorthy, 2011 .

Full bandgap defect state characterization of β-Ga2O3 grown by metal organic chemical vapor deposition

S. Ringel, E. Farzana, Hongping Zhao, 2020 .

Deep levels in a-plane, high Mg-content MgxZn1−xO epitaxial layers grown by molecular beam epitaxy

S. Ringel, J. Chauveau, A. Hierro, 2012 .

Anti-phase domain-free GaAs on Ge substrates grown by molecular beam epitaxy for space solar cell applications

E. Fitzgerald, S. Ting, R. Sieg, 1997, Conference Record of the Twenty Sixth IEEE Photovoltaic Specialists Conference - 1997.

S. Ringel, M. Mills, B. Galiana, 2013 .

Metal/BaTiO3/β-Ga2O3 dielectric heterojunction diode with 5.7 MV/cm breakdown field

S. Ringel, S. Rajan, A. Arehart, 2019, Applied Physics Letters.

EVIDENCE FOR A DOMINANT MIDGAP TRAP IN N-ZNSE GROWN BY MOLECULAR BEAM EPITAXY

S. Ringel, E. Pelucchi, D. Kwon, 1999 .

Unusual Formation of Point-Defect Complexes in the Ultrawide-Band-Gap Semiconductor β−Ga2O3

Jared M. Johnson, D. Muller, C. Walle, 2019, Physical Review X.

The Critical Role of AlInP Window Design in III–V Rear-Emitter Solar Cells

S. Ringel, T. Grassman, Daniel L. Lepkowski, 2020, IEEE Journal of Photovoltaics.

Deep level defects throughout the bandgap of (010) β-Ga2O3 detected by optically and thermally stimulated defect spectroscopy

S. Ringel, E. Farzana, A. Arehart, 2016 .

Access-Region Defect Spectroscopy of DC-Stressed N-Polar GaN MIS-HEMTs

S. Kolluri, S. P. DenBaars, U. K. Mishra, 2012, IEEE Electron Device Letters.

Investigation of trapping effects on AlGaN/GaN HEMT under DC accelerated life testing

S. Ringel, P. Saunier, A. Arehart, 2016, 2016 IEEE International Reliability Physics Symposium (IRPS).

Correlative Defect Characterization in Semiconductors via Electron Channeling Contrast Imaging and Scanning Deep Level Transient Spectroscopy

S. Ringel, T. Grassman, A. Arehart, 2018, Microscopy and Microanalysis.

Spatial correlation of the EC-0.57 eV trap state with edge dislocations in epitaxial n-type gallium nitride

S. Ringel, J. Speck, T. Grassman, 2018, Journal of Applied Physics.

Investigation of Trap-Induced Threshold Voltage Instability in GaN-on-Si MISHEMTs

S. Ringel, S. Krishnan, S. Pendharkar, 2019, IEEE Transactions on Electron Devices.

Topographic and electronic studies of wedge-shape surface defects on AlGaAs/GaAs films grown on Ge substrates

J. Boeckl, R. Sieg, S. Ringel, 1999 .

Mechanism of Si doping in Plasma Assisted MBE Growth of \b{eta}-Ga2O3

S. Ringel, S. Rajan, S. Krishnamoorthy, 2019, 1908.01101.

Growth and properties of AlGaInP resonant cavity light emitting diodes on Ge∕SiGe∕Si substrates

J. Boeckl, M. Lee, E. Fitzgerald, 2005 .

Growth and Properties of AlGaInP Resonant Cavity Light Emitting Diodes (RCLEDs)on Ge/SiGe/Si Substrates

J. Boeckl, M. Lee, E. Fitzgerald, 2003 .

Influence of growth temperature on defect states throughout the bandgap of MOCVD-grown β-Ga2O3

S. Ringel, Hongping Zhao, A. Arehart, 2020 .

Breakdown Characteristics of $\beta$ -(Al0.22Ga0.78)2O3/Ga2O3 Field-Plated Modulation-Doped Field-Effect Transistors

S. Lodha, S. Ringel, S. Rajan, 2019, IEEE Electron Device Letters.

Effect of buffer iron doping on delta-doped β-Ga2O3 metal semiconductor field effect transistors

S. Lodha, S. Ringel, S. Rajan, 2018, Applied Physics Letters.

Electrical Properties 3

S. Ringel, A. Arehart, 2020 .

Identification of critical buffer traps in Si δ-doped β-Ga2O3 MESFETs

S. Lodha, S. Ringel, S. Rajan, 2019, Applied Physics Letters.

Electrostatic Engineering Using Extreme Permittivity Materials for Ultra-Wide Bandgap Semiconductor Transistors

S. Ringel, S. Rajan, Hongping Zhao, 2020, IEEE Transactions on Electron Devices.

Metamorphic tunnel junctions for high efficiency III-V/IV multi-junction solar cell technology

Andrew M. Carlin, S. Ringel, J. Carlin, 2013, 2013 IEEE 39th Photovoltaic Specialists Conference (PVSC).

Rapid misfit dislocation characterization in heteroepitaxial III-V/Si thin films by electron channeling contrast imaging

M. Graef, S. Ringel, J. Carlin, 2014 .

Carrier Trapping and Recombination at Point Defects and Dislocations in MOCVD n-GaN

S. Denbaars, S. Ringel, U. Mishra, 2001 .

Applications of Electron Channeling Contrast Imaging for the Rapid Characterization of Extended Defects in III–V/Si Heterostructures

Steven A. Ringel, David W. McComb, Yoosuf N. Picard, 2015, IEEE Journal of Photovoltaics.

Comparison of deep level incorporation in ammonia and rf‐plasma assisted molecular beam epitaxy n‐GaN films

Steven A. Ringel, Christiane Poblenz, James S. Speck, 2008 .

Direct observation of 0.57 eV trap-related RF output power reduction in AlGaN/GaN high electron mobility transistors

Steven A. Ringel, Umesh K. Mishra, Siddharth Rajan, 2013 .

Deep level optical and thermal spectroscopy of traps in n-GaN grown by ammonia molecular beam epitaxy

Steven A. Ringel, Christiane Poblenz, James S. Speck, 2008 .

Impact of deep levels on the electrical conductivity and luminescence of gallium nitride codoped with carbon and silicon

Steven A. Ringel, James S. Speck, Daniel S. Green, 2005 .

Hydrogen passivation of deep levels in n–GaN

Steven A. Ringel, James S. Speck, Umesh K. Mishra, 2000 .

Deep level traps in GaN LEDs grown by metal organic vapour phase epitaxy on an 8 inch Si(111) substrate

Steven A. Ringel, Soo Jin Chua, Eugene A. Fitzgerald, 2016 .

Effect of Silicon Front Surface Doping Profile on GaP/Si Heterostructure for III-V/GaP/Si Multi-junction Solar Cells

S. Ringel, A. Ho-baillie, J. Carlin, 2018, 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC).

High temperature step-flow growth of gallium phosphide by molecular beam epitaxy and metalorganic chemical vapor deposition

Steven A. Ringel, Tyler J. Grassman, John A. Carlin, 2011 .

Expanding the palette: Metamorphic strategies over multiple lattice constant ranges for extending the spectrum of accessible photovoltaic materials

Steven A. Ringel, Andrew M. Carlin, Javier Grandal, 2011, 2011 37th IEEE Photovoltaic Specialists Conference.

Development of high efficiency p/sup +//n InP solar cells for hetero-epitaxial applications

D. Scheiman, N. Fatemi, S. Ringel, 1996, Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996.

Atomic layer diffusion and electronic structure at In0.53Ga0.47As/InP interfaces

M. Hudait, S. Ringel, L. Brillson, 2004 .

Photocapacitance study of bulk deep levels in ZnSe grown by molecular-beam epitaxy

S. Ringel, E. Pelucchi, D. Kwon, 2000 .

Positron annihilation spectroscopy of AlGaAs/GaAs interfaces in metalorganic chemical vapor deposition grown GaAs heterojunction solar cells

B. Nielsen, S. Ringel, A. Rohatgi, 1988 .

An approach toward 25-percent efficient GaAs heteroface solar cells

S. Ringel, A. Rohatgi, S. Tobin, 1989 .

Material quality and design optimization for high efficiency GaAs solar cells

S. Ringel, A. Rohatgi, 1988, Conference Record of the Twentieth IEEE Photovoltaic Specialists Conference.

Separation of bulk and surface electron transport in metamorphic InAs layers using quantitative mobility spectrum analysis

Andrew M. Carlin, S. Ringel, A. Arehart, 2008 .

Metamorphic Tunnel Junctions Grown Via MOCVD Designed for GaAs0.75P0.25/Si Tandem Solar Cells

S. Ringel, T. Grassman, Daniel L. Lepkowski, 2021, IEEE Journal of Photovoltaics.

Development of Low-TDD GaAsyP1-y/GaP/Si Metamorphic Materials for High-Efficiency III-V/Si Photovoltaics

Ari N. Blumer, S. Ringel, T. Grassman, 2020, 2020 47th IEEE Photovoltaic Specialists Conference (PVSC).

Toward >25% Efficient Monolithic Epitaxial GaAsP/Si Tandem Solar Cells

S. Ringel, A. Ho-baillie, D. Derkacs, 2019, 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC).

Comparative Study of ∼2.05 eV Lattice-Matched and Metamorphic (Al)GaInP Solar Cells Grown by MOCVD

S. Ringel, T. Grassman, Daniel L. Lepkowski, 2018, IEEE Journal of Photovoltaics.

Investigations of metamorphic (Al)GaInP for III–V multijunction photovoltaics

S. Ringel, T. Grassman, P. Paul, 2015, 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC).

High-quality InAsyP1-y step-graded buffer by molecular-beam epitaxy

M. Hudait, S. Ringel, J. Speck, 2003 .

Evidence for the formation of polycrystalline silicon by argon implantation and its passivation by atomic hydrogen

S. Ringel, S. Ashok, H. Chien, 1986 .

Comparison of mixed anion, InAsyP1−y and mixed cation, InxAl1−xAs metamorphic buffers grown by molecular beam epitaxy on (100) InP substrates

Steven A. Ringel, Mantu K. Hudait, C. Tivarus, 2004 .

CHARACTERIZATION OF THE TRANSPORT PROPERTIES OF CHANNEL DELTA-DOPED STRUCTURES BY LIGHT-MODULATED SHUBNIKOV-DE HAAS MEASUREMENTS

S. Ringel, S. Bibyk, S. Alterovitz, 1995 .

Correlation of a generation-recombination center with a deep level trap in GaN

E. Fitzgerald, S. Chua, S. Ringel, 2015 .

Molecular beam epitaxy of N-polar InGaN

S. Ringel, S. Rajan, D. Nath, 2010 .

Dual junction GaInP/GaAs solar cells grown on metamorphic SiGe/Si substrates with high open circuit voltage

E. Fitzgerald, S. Ringel, C. L. Andre, 2006, IEEE Electron Device Letters.

Electrical characterization of n-type Al0.30Ga0.70N Schottky diodes

Steven A. Ringel, A. A. Allerman, Aaron R. Arehart, 2011 .

Impact of Ga/N flux ratio on trap states in n-GaN grown by plasma-assisted molecular-beam epitaxy

Steven A. Ringel, James S. Speck, Umesh K. Mishra, 2002 .

Optically and thermally detected deep levels in n-type Schottky and p+-n GaN diodes

Steven A. Ringel, James S. Speck, Umesh K. Mishra, 2000 .

Designing Bottom Silicon Solar Cells for Multijunction Devices

M. Green, G. Conibeer, S. Ringel, 2015, IEEE Journal of Photovoltaics.

Design of bottom silicon solar cell for multijunction devices

M. Green, G. Conibeer, S. Ringel, 2013, 2013 IEEE 39th Photovoltaic Specialists Conference (PVSC).

Deep-level defects in InGaAsN grown by molecular-beam epitaxy

A. Allerman, J. Klem, S. Ringel, 2002 .

Deep levels and their impact on generation current in Sn-doped InGaAsN

Steven A. Ringel, Andrew A. Allerman, R. M. Sieg, 2001 .

High Performance Metamorphic Tunnel Junctions for GaAsP/Si Tandem Solar Cells Grown via MOCVD

S. Ringel, J. Carlin, T. Grassman, 2018, 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC).

Designing an Epitaxially-Integrated DBR for Dislocation Mitigation in Monolithic GaAsP/Si Tandem Solar Cells

S. Ringel, T. Grassman, Daniel L. Lepkowski, 2021, IEEE Journal of Photovoltaics.

Development and Characterization of III-V/Si Multijunction Photovoltaics for Space Application

S. Ringel, D. Derkacs, T. Grassman, 2019, 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC).

GaAs0.75P0.25/Si Dual-Junction Solar Cells Grown by MBE and MOCVD

S. Ringel, J. Carlin, T. Grassman, 2016, IEEE Journal of Photovoltaics.

Anti-phase domain-free growth of GaAs on offcut (001) Ge wafers by molecular beam epitaxy with suppressed Ge outdiffusion

Steven A. Ringel, S. M. Ting, R. M. Sieg, 1998 .

Deep Levels in p- and n-type InGaAsN for High Efficiency Multi-Junction III-V Solar Cells

R.J. Kaplar, D. Kwon, S.A. Ringel, 1999 .

Reabsorption, band‐gap narrowing, and the reconciliation of photoluminescence spectra with electrical measurements for epitaxial n‐InP

R. Sieg, S. Ringel, 1996 .

The Effect of The Zn Interstitial Defect on the Performance of p/n InP Solar Cells

D. Scheiman, P. Jenkins, M. Stan, 1997 .

Atomic diffusion and band lineups at In0.53Ga0.47As-on-InP heterointerfaces

M. Hudait, S. Ringel, L. Brillson, 2005 .

Optimization of a GaAsP Top Cell for Implementation in a III-V/Si Tandem Structure

S. Ringel, T. Grassman, Daniel L. Lepkowski, 2017 .

Impact of dislocation densities on n+∕p and p+∕n junction GaAs diodes and solar cells on SiGe virtual substrates

M. Lee, E. Fitzgerald, S. Ringel, 2005 .

Electron Channeling Contrast Imaging for Rapid III-V Heteroepitaxial Characterization.

S. Ringel, T. Grassman, D. McComb, 2015, Journal of visualized experiments : JoVE.

Impact of dislocations on minority carrier electron and hole lifetimes in GaAs grown on metamorphic SiGe substrates

J. Boeckl, M. Lee, E. Fitzgerald, 2004 .

High-performance metamorphic tunnel junctions for III–V/Si multijunction solar cells

S. Ringel, J. Carlin, T. Grassman, 2015, 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC).

Metamorphic GaAsP Tunnel Junctions for High-Efficiency III–V/IV Multijunction Solar Cell Technology

Andrew M. Carlin, S. Ringel, J. Carlin, 2014, IEEE Journal of Photovoltaics.

Epitaxially-grown metamorphic GaAsP/Si dual-junction solar cells

S. A. Ringel, S. Ringel, J. Carlin, 2013, 2013 IEEE 39th Photovoltaic Specialists Conference (PVSC).

Impact of proton irradiation on deep level states in n-GaN

En Xia Zhang, Steven A. Ringel, James S. Speck, 2013 .

Impact of carbon on trap states in n-type GaN grown by metalorganic chemical vapor deposition

Steven A. Ringel, James S. Speck, Umesh K. Mishra, 2004 .

Metalorganic Chemical Vapor Deposition Gallium Nitride with Fast Growth Rate for Vertical Power Device Applications

S. Ringel, Hongping Zhao, A. Arehart, 2021, physica status solidi (a).

Effect of nitrogen plasma power on defect levels in Ni/n-GaN Schottky diodes grown by molecular beam epitaxy

S. Ringel, J. Speck, C. Poblenz, 2010 .

Application of pyrometric interferometry to the in situ monitoring of In0.52Al0.48As, In0.53Ga0.47As, and quaternary alloy growth on InP substrates

R. Sieg, S. Ringel, R. Sacks, 1997 .

Gate length scaling study of InAlAs/InGaAs/InAsP composite channel HEMTs

M. Hudait, S. Ringel, Hyeongnam Kim, 2007 .

Loss Analysis and Design Strategies Enabling >23% GaAsP/Si Tandem Solar Cells

S. Ringel, A. Ho-baillie, A. Soeriyadi, 2020, 2020 47th IEEE Photovoltaic Specialists Conference (PVSC).

Ideal GaP/Si heterostructures grown by MOCVD: III-V/active-Si subcells, multijuntions, and MBE-to-MOCVD III-V/Si interface science

Andrew M. Carlin, G. Conibeer, M. Green, 2013, 2013 IEEE 39th Photovoltaic Specialists Conference (PVSC).

EDS Executive Director

Narain D. Arora, F. Dimroth, S. Kurinec, 2015 .

Deep trap-induced dynamic on-resistance degradation in GaN-on-Si power MISHEMTs

W. Sun, Z. Zhang, D. W. Cardwell, 2016, Microelectron. Reliab..

Direct comparison of traps in InAlN/GaN and AlGaN/GaN high electron mobility transistors using constant drain current deep level transient spectroscopy

Steven A. Ringel, Umesh K. Mishra, S. P. DenBaars, 2013 .

Next generation defect characterization in nitride HEMTs

Steven A. Ringel, Christiane Poblenz, James S. Speck, 2011 .

Quantitative observation and discrimination of AlGaN- and GaN-related deep levels in AlGaN∕GaN heterostructures using capacitance deep level optical spectroscopy

Steven A. Ringel, James S. Speck, Umesh K. Mishra, 2006 .

Proton irradiation effects on deep level states in Mg-doped p-type GaN grown by ammonia-based molecular beam epitaxy

En Xia Zhang, Steven A. Ringel, James S. Speck, 2015 .

Characterization of majority and minority carrier deep levels in p-type GaN:Mg grown by molecular beam epitaxy using deep level optical spectroscopy

Steven A. Ringel, Christiane Poblenz, James S. Speck, 2008 .

Low-energy hydrogen implantation for silicon Schottky barrier modification

S. Ringel, S. Ashok, 1986 .

Evidence for enhanced zinc interstitial concentration in strain‐relaxed heteroepitaxial indium phosphide

R. Sieg, S. Ringel, B. Chatterjee, 1995 .

High minority-carrier lifetimes in GaAs grown on low-defect-density Ge/GeSi/Si substrates

Steven A. Ringel, S. M. Ting, Thomas A. Langdo, 1998 .

β-Gallium oxide power electronics

O. Bierwagen, V. Mehrotra, S. Ringel, 2022, APL Materials.

Toward device-quality GaAs growth by molecular beam epitaxy on offcut Ge/Si1−xGex/Si substrates

Steven A. Ringel, S. M. Ting, Thomas A. Langdo, 1998 .

Monolithic integration of AlGaInP laser diodes on SiGe∕Si substrates by molecular beam epitaxy

Steven A. Ringel, O. Kwon, Eugene A. Fitzgerald, 2006 .

Chapter 6 – Electronic Properties and Deep Levels in Germanium-Silicon

S. Ringel, 1998 .

Structural, electronic, and luminescence investigation of strain‐relaxation induced electrical conductivity type conversion in GeSi/Si heterostructures

E. Fitzgerald, S. Ringel, J. Michel, 1996 .

Effect of composition on deep levels in heteroepitaxial GexSi1−x layers and evidence for dominant intrinsic recombination-Generation in relaxed ge layers on Si

E. Fitzgerald, S. Ringel, P. Grillot, 1996 .

A study of polycrystalline Cd(Zn, Mn)Te/Cds films and interfaces

S. Ringel, A. Rohatgi, W. Carter, 1990 .

Investigation of the accuracy of pyrometric interferometry in determining AlxGa1−xAs growth rates and compositions

Steven A. Ringel, R. M. Sieg, R. N. Sacks, 1996 .

An improved understanding of efficiency limiting defects in polycrystalline CdTe/CdS solar cells

S. Ringel, A. Rohatgi, R. Sudharsanan, 1991, The Conference Record of the Twenty-Second IEEE Photovoltaic Specialists Conference - 1991.

Identifying the source of reduced performance in 1-stage-grown Cu(In, Ga)Se2 solar cells

S. Ringel, T. Grassman, P. Paul, 2016, 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC).

Direct nm-scale spatial mapping of traps in CIGS

S. Ringel, T. Grassman, P. Paul, 2015, 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC).

Direct nm-Scale Spatial Mapping of Traps in CIGS

S. Ringel, T. Grassman, P. Paul, 2015, IEEE Journal of Photovoltaics.

Identifying the source of reduced performance in 1-stage-grown Cu(In,Ga)Se2 solar cells

S. Ringel, T. Grassman, P. Paul, 2017, 2017 IEEE 44th Photovoltaic Specialist Conference (PVSC).

Strain relaxation properties of InAsyP1−y metamorphic materials grown on InP substrates

Steven A. Ringel, Mantu K. Hudait, M. Hudait, 2009 .

Carrier compensation and scattering mechanisms in Si-doped InAsyP1−y layers grown on InP substrates using intermediate InAsyP1−y step-graded buffers

M. Hudait, S. Ringel, J. Lindemuth, 2006 .

Monolithically integrated thin film III-V/Si solar panel on wafer for active power management

E. Fitzgerald, J. Hennessy, S. Ringel, 2011, 2011 37th IEEE Photovoltaic Specialists Conference.

Evaluation of Low-Temperature Saturation Velocity in $\beta$ -(AlxGa1–x)2O3/Ga2O3 Modulation-Doped Field-Effect Transistors

S. Ringel, S. Rajan, A. Arehart, 2019, IEEE Transactions on Electron Devices.

Demonstration of self-aligned β-Ga2O3 δ-doped MOSFETs with current density >550 mA/mm

S. Ringel, S. Rajan, M. Brenner, 2023, Applied Physics Letters.

Erratum: “Deep level defects throughout the bandgap of (010) β-Ga2O3 detected by optically and thermally stimulated defect spectroscopy” [Appl. Phys. Lett. 108, 052105 (2016)]

S. Ringel, E. Farzana, A. Arehart, 2016 .

Direct measurement of quantum confinement effects at metal to quantum-well nanocontacts.

M. Hudait, S. Ringel, J. Pelz, 2005, Physical review letters.

Probing charge transport and background doping in MOCVD grown (010) ${\beta}$-Ga$_{2}$O$_{3}$

S. Ringel, S. Rajan, Hongping Zhao, 2020, 2004.13089.

Trapping Effects in Si -Doped -Ga2O3 MESFETs on an Fe-Doped -Ga2O3 Substrate

S. Lodha, S. Ringel, S. Rajan, 2018, IEEE Electron Device Letters.

Effects of annealing and surface preparation on the properties of polycrystalline CdZnTe films grown by molecular beam epitaxy

S. Ringel, A. Rohatgi, H. Gillis, 1990 .

The effects of CdCl2 on the electronic properties of molecular‐beam epitaxially grown CdTe/CdS heterojunction solar cells

Ajeet Rohatgi, Steven A. Ringel, M. H. MacDougal, 1991 .

Growth and process optimization of CdTe and CdZnTe polycrystalline films for high efficiency solar cells

Ajeet Rohatgi, Steven A. Ringel, M. H. MacDougal, 1991 .

High electron density β-(Al0.17Ga0.83)2O3/Ga2O3 modulation doping using an ultra-thin (1 nm) spacer layer

S. Ringel, S. Rajan, A. Arehart, 2020, Journal of Applied Physics.

Deep level defects in Ge-doped (010) β-Ga2O3 layers grown by plasma-assisted molecular beam epitaxy

Steven A. Ringel, James S. Speck, Esmat Farzana, 2018 .

Hydrogen-extended defect interactions in heteroepitaxial InP materials and devices

Steven A. Ringel, S. Ringel, 1997 .

Direct Determination of Energy Band Alignments of Ni/Al2O3/GaN MOS Structures Using Internal Photoemission Spectroscopy

S. Ringel, J. Speck, A. Arehart, 2014, Journal of Electronic Materials.

23.4% monolithic epitaxial GaAsP/Si tandem solar cells and quantification of losses from threading dislocations

S. Ringel, A. Ho-baillie, A. Soeriyadi, 2021 .

Interface trap characterization of atomic layer deposition Al2O3/GaN metal-insulator-semiconductor capacitors using optically and thermally based deep level spectroscopies

Steven A. Ringel, James S. Speck, Aaron R. Arehart, 2013 .

Range of defect morphologies on GaAs grown on offcut (001) Ge substrates

E. Fitzgerald, S. Ting, R. Sieg, 1998 .

Impact of substrate temperature on the incorporation of carbon-related defects and mechanism for semi-insulating behavior in GaN grown by molecular beam epitaxy

Steven A. Ringel, Christiane Poblenz, James S. Speck, 2006 .

A method to determine deep level profiles in highly compensated, wide band gap semiconductors

S. Ringel, A. Arehart, A. Armstrong, 2005 .

Metamorphic In0.7Al0.3As/In0.69Ga0.31As thermophotovoltaic devices grown on graded InAsyP1−y buffers by molecular beam epitaxy

Steven A. Ringel, Mantu K. Hudait, M. Hudait, 2009 .

Proton radiation effects on electronic defect states in MOCVD-grown (010) β-Ga2O3

S. Ringel, G. Burns, A. Arehart, 2023, Journal of Applied Physics.

Deep level defects in low-pressure chemical vapor deposition grown (010) β-Ga2O3

S. Ringel, A. Arehart, H. Ghadi, 2022, APL Materials.

Influence of neutron irradiation on deep levels in Ge-doped (010) β-Ga2O3 layers grown by plasma-assisted molecular beam epitaxy

S. Ringel, J. Speck, E. Farzana, 2019, APL Materials.

Impact of deep level defects induced by high energy neutron radiation in β-Ga2O3

S. Ringel, E. Farzana, A. Arehart, 2019, APL Materials.

The design of single-junction GaAs and dual-junction GaAs/Si in the presence of threading dislocation density

M. Green, S. Ringel, A. Ho-baillie, 2015, 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC).

1EV GaN[subscript x]As[subscript 1-x-y]Sb[subscript y] material for lattice-matched III-V solar cell implementation on GaAs and Ge

Andrew M. Carlin, M. González, E. Fitzgerald, 2010 .

1EV GANxAS1-x-ySBy material for lattice-matched III–V solar cell implementation on GaAs and Ge

Kah Pin Chen, Andrew M. Carlin, E. Fitzgerald, 2009, 2009 34th IEEE Photovoltaic Specialists Conference (PVSC).

Impact of GaAs buffer thickness on electronic quality of GaAs grown on graded Ge/GeSi/Si substrates

Steven A. Ringel, Mayank T. Bulsara, B. M. Keyes, 2000 .

Probing Charge Transport and Background Doping in Metal‐Organic Chemical Vapor Deposition‐Grown (010) β‐Ga2O3

S. Ringel, S. Rajan, Hongping Zhao, 2020, physica status solidi (RRL) – Rapid Research Letters.

A study of target heating in low‐energy ion‐beam processing

S. Ringel, S. Ashok, S. Fonash, 1986 .

Growth and characterization of epitaxial FexAl1−x/(In,Al)As/InP and III–V/FexAl1−x/(In,Al)As/InP structures

S. Ringel, M. Goorsky, D. Wilt, 1999 .

Correlation of proton irradiation induced threshold voltage shifts to deep level traps in AlGaN/GaN heterostructures

En Xia Zhang, Steven A. Ringel, James S. Speck, 2016 .

Role of subsurface defects in metal-ZnO(0001¯) Schottky barrier formation

D. Look, S. Ringel, L. Brillson, 2007 .

In Situ and Ex Situ Investigations of KF Postdeposition Treatment Effects on CIGS Solar Cells

A. Rockett, S. Ringel, R. Collins, 2017, IEEE Journal of Photovoltaics.

Interface trap evaluation of Pd/Al2O3/GaN metal oxide semiconductor capacitors and the influence of near-interface hydrogen

Steven A. Ringel, Yoshio Nishi, T. P. Ma, 2013 .

Optically-aligned visible/near-infrared dual-band photodetector materials and devices on GaAs using metamorphic epitaxy

Steven A. Ringel, Michael J. Mills, Tyler J. Grassman, 2011 .

Spatially-discriminating trap characterization methods for HEMTs and their application to RF-stressed AlGaN/GaN HEMTs

S. A. Ringel, B. Winningham, S. Ringel, 2010, 2010 International Electron Devices Meeting.

Final results from the MISSE5 GaAs on Si solar cell experiment

Steven A. Ringel, Phillip P. Jenkins, David M. Wilt, 2008, 2008 33rd IEEE Photovoltaic Specialists Conference.

Influence of metal choice on (010) β-Ga2O3 Schottky diode properties

Steven A. Ringel, Esmat Farzana, Pran K. Paul, 2017 .

Toward metamorphic multijunction GaAsP/Si photovoltaics grown on optimized GaP/Si virtual substrates using anion-graded GaAsyP1-y buffers

S. A. Ringel, Andrew M. Carlin, S. Rajagopalan, 2009, 2009 34th IEEE Photovoltaic Specialists Conference (PVSC).

Erratum: “Deep level defects in proton radiated GaAs grown on metamorphic SiGe/Si substrates” [J. Appl. Phys. 100, 034503 (2006)]

E. J. Fitzgerald, S. Messenger, M. González, 2006 .

High-efficiency cadmium and zinc-telluride-based thin-film solar cells

S. Ringel, A. Rohatgi, A. Erbil, 1989 .

Growth and characterization of CdMnTe and CdZnTe polycrystalline thin films for solar cells

E. L. Meeks, K. T. Pollard, S. Ringel, 1988 .

Electrical deactivation of interstitial Zn in heteroepitaxial InP by hydrogen and its effect on electronic properties

S. Ringel, B. Chatterjee, 1998 .

Effect of extended defects on the formation and dissociation kinetics of Zn–H complexes in heteroepitaxial p‐type InP layers

S. Ringel, B. Chatterjee, 1996 .

Velocity saturation in La-doped BaSnO3 thin films

A. Janotti, S. Stemmer, S. Ringel, 2019, Applied Physics Letters.

Deep traps in nonpolar m-plane GaN grown by ammonia-based molecular beam epitaxy

Steven A. Ringel, James S. Speck, Z. Zhang, 2012 .

Plasma-assisted deposition and characterization of Al2O3 dielectric layers on (001) β -Ga2O3

S. Ringel, A. Islam, S. Rajan, 2023, Applied Physics Letters.

Influence of V/III growth flux ratio on trap states in m-plane GaN grown by ammonia-based molecular beam epitaxy

S. Ringel, J. Speck, A. Arehart, 2012 .

Development of epitaxial 2- and 3-junction III-V/Si solar cells

S. Ringel, J. Carlin, T. Grassman, 2016, 2017 IEEE 44th Photovoltaic Specialist Conference (PVSC).

GaAsP/Si dual-junction solar cells grown by MBE and MOCVD

S. Ringel, J. Carlin, T. Grassman, 2015, 2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC).

High-lifetime GaAs on Si using GeSi buffers and its potential for space photovoltaics

Steven A. Ringel, Mayank T. Bulsara, John A. Carlin, 2001 .

Improving GaAsP/Si Tandem Solar Cells Using Silicon Passivated Contacts

S. Ringel, E. Warren, T. Grassman, 2020, 2020 47th IEEE Photovoltaic Specialists Conference (PVSC).

Impact of threading dislocations on both n/p and p/n single junction GaAs cells grown on Ge/SiGe/Si substrates

A. Khan, M. González, M. Hudait, 2002, Conference Record of the Twenty-Ninth IEEE Photovoltaic Specialists Conference, 2002..

0.6-eV bandgap In/sub 0.69/Ga/sub 0.31/As thermophotovoltaic devices grown on InAs/sub y/P/sub 1-y/ step-graded buffers by molecular beam epitaxy

M. Hudait, S. Ringel, M. Palmisiano, 2003, IEEE Electron Device Letters.

High efficiency GaAs-on-Si solar cells with high V/sub oc/ using graded GeSi buffers

Mantu K. Hudait, David M. Wilt, Thomas A. Langdo, 2000, Conference Record of the Twenty-Eighth IEEE Photovoltaic Specialists Conference - 2000 (Cat. No.00CH37036).

Scanning force microscopy studies of GaAs films grown on offcut Ge substrates

E. Fitzgerald, S. Ting, R. Sieg, 1998 .

Electrical characterization of electron and proton-induced defects in p+n GaAs photodiodes: EBIC study

Andrew M. Carlin, S. Messenger, R. Walters, 2010, 2010 35th IEEE Photovoltaic Specialists Conference.

Effects of Applied Bias and High Field Stress on the Radiation Response of GaN/AlGaN HEMTs

En Xia Zhang, Rong Jiang, Steven A. Ringel, 2015, IEEE Transactions on Nuclear Science.

Pulsed-IV Pulsed-RF Cold-FET Parasitic Extraction of Biased AlGaN/GaN HEMTs Using Large Signal Network Analyzer

Patrick Roblin, Christiane Poblenz, Siddharth Rajan, 2010, IEEE Transactions on Microwave Theory and Techniques.

Deep Level Characterization of Interface-Engineered ZnSe Layers Grown by Molecular Beam Epitaxy on GaAs

S. Ringel, D. Kwon, A. Hierro, 1998 .

Additive phase noise measurements of AlGaN/GaN HEMTs using a large signal network analyzer and a tunable monochromatic light source

Patrick Roblin, Andrew Malonis, Christiane Poblenz, 2009, 2009 74th ARFTG Microwave Measurement Conference.

High-Field Stress, Low-Frequency Noise, and Long-Term Reliability of AlGaN/GaN HEMTs

En Xia Zhang, Steven A. Ringel, James S. Speck, 2016, IEEE transactions on device and materials reliability.

Dislocation Interactions And Their Impact On Electrical Properties Of GeSi-Based Heterostructures

S. Ringel, P. Grillot, 1996 .

Identification of compositionally invariant deep levels introduced by plastic strain in epitaxial Ge0.30Si0.70 and deformed bulk Si

S. Ringel, P. Grillot, 1996 .

Rapid characterization of extended defects in III–V/Si by electron channeling contrast imaging

S. Ringel, J. Carlin, T. Grassman, 2014, 2014 IEEE 40th Photovoltaic Specialist Conference (PVSC).

Spatially-resolved spectroscopic measurements of Ec − 0.57 eV traps in AlGaN/GaN high electron mobility transistors

Steven A. Ringel, James S. Speck, Umesh K. Mishra, 2013 .

All manuscripts, correspondence and communication should be directed to IEEE/EDS Publications Office

Adrian M. Ionescu, P. K. L. Yu, John R. Tower, 2010 .

Investigations of high-performance GaAs solar cells grown on Ge-Si/sub 1-x/Ge/sub x/-Si substrates

M.A. Smith, S. Ringel, J. Carlin, 2005, IEEE Transactions on Electron Devices.

Proceedings of the Symposium on Large Area Wafer Growth and Processing for Electronic and Photonic Devices and the twentieth State-of-the-Art Program on Compound Semiconductors (SOTAPOCS XX)

Fan Ren, Sotapocs, D. N. Buckley, 1995 .