Extreme Bandgap Semiconductors

The last two decades witnessed revolutionary advances in electronics and photonics by moving from ~1 electron Volt gap semiconductors (Silicon, Gallium Arsenide) to ~3 electron Volt Gallium Nitride and Silicon Carbide. This enabled energy-efficient light emitting diodes as replacement of incandescent bulbs, high-voltage transistors that are cutting down wasted energy in electrical devices and machinery, and significantly expanded our fundamental knowledge of the materials science of semiconductors. Similar major advances are expected by aiming at extreme-bandgap semiconductors with energy gaps almost twice of that of the wide-bandgap semiconductors. In addition to the new science, such materials should enable advances in healthcare and monitoring by creating deep-ultraviolet light-emitting diodes and lasers, and by significantly improving the efficiency and capability of semiconductors for electrical power conversion. The proposed project will result in the training of graduate students in a fascinating emerging field of extreme bandgap semiconductor material science, with their many fundamental electronic, optical, and thermoelectric properties. In addition to expanding existing outreach programs, new activities with a special focus on high-school students and underrepresented groups via Research Experiences for Teachers programs and direct visits for in-class demonstrations are proposed. That the team is distributed between Cornell, Michigan, and Stanford with complementary expertise will be exploited by regular exchange of graduate students for experiments, as well as theory and modeling work, to foster a truly collaborative mindset in the project. The dissemination of research by journal publications, presentations at conferences, its inclusion in courses taught by the invsetigators, and online (e.g. nanoHub) will make possible the outreach of the research results to the widest possible audience.

Publications

Epitaxial ScxAl1−xN on GaN exhibits attractive high-K dielectric properties

J. Casamento, H. Lee, T. Maeda, V. Gund, K. Nomoto, L. van Deurzen, W. Turner, P. Fay, S. Mu, C. G. Van de Walle, A. Lal, H. (. Xing, and D. Jena

4/11/2022

Very High Density (>10¹⁴ cm⁻²) Polarization‐Induced 2D Hole Gases Observed in Undoped Pseudomorphic InGaN/AlN Heterostructures

R. Chaudhuri, Z. Zhang, H. G. Xing, and D. Jena

1/5/2022

Momentum-resolved electronic structure and band offsets in an epitaxial NbN/GaN superconductor/semiconductor heterojunction

T. Yu, J. Wright, G. Khalsa, B. Pamuk, C. S. Chang, Y. Matveyev, X. Wang, T. Schmitt, D. Feng, D. A. Muller, H. G. Xing, D. Jena, and V. N. Strocov

12/24/2021

In Situ Crystalline AlN Passivation for Reduced RF Dispersion in Strained‐Channel AlN/GaN/AlN High‐Electron‐Mobility Transistors

R. Chaudhuri, A. Hickman, J. Singhal, J. Casamento, H. G. Xing, and D. Jena

10/14/2021

Strong effect of scandium source purity on chemical and electronic properties of epitaxial ScxAl1−xN/GaN heterostructures

J. Casamento, H. Lee, C. S. Chang, M. F. Besser, T. Maeda, D. A. Muller, H. (. Xing, and D. Jena

9/1/2021

High-conductivity polarization-induced 2D hole gases in undoped GaN/AlN heterojunctions enabled by impurity blocking layers

R. Chaudhuri, Z. Chen, D. A. Muller, H. G. Xing, and D. Jena

7/13/2021

Toward the predictive discovery of ambipolarly dopable ultra-wide-band-gap semiconductors: The case of rutile GeO2

S. Chae, K. Mengle, K. Bushick, J. Lee, N. Sanders, Z. Deng, Z. Mi, P. F. P. Poudeu, H. Paik, J. T. Heron, and E. Kioupakis

6/28/2021

Electric Fields and Surface Fermi Level in Undoped GaN/AlN Two‐Dimensional Hole Gas Heterostructures

Ł. Janicki, R. Chaudhuri, S. J. Bader, H. G. Xing, D. Jena, and R. Kudrawiec

2/18/2021

N-polar GaN/AlN resonant tunneling diodes

Y. Cho, J. Encomendero, S. Ho, H. G. Xing, and D. Jena

10/5/2020

Prospects for Wide Bandgap and Ultrawide Bandgap CMOS Devices

S. J. Bader, H. Lee, R. Chaudhuri, S. Huang, A. Hickman, A. Molnar, H. G. Xing, D. Jena, H. W. Then, N. Chowdhury, and T. Palacios

10/1/2020

Guiding Principles for Trench Schottky Barrier Diodes Based on Ultrawide Bandgap Semiconductors: A Case Study in Ga₂O₃

W. Li, K. Nomoto, Z. Hu, D. Jena, and H. G. Xing

10/1/2020

Bottom tunnel junction blue light-emitting field-effect transistors

S. Bharadwaj, K. Lee, K. Nomoto, A. Hickman, L. van Deurzen, V. Protasenko, H. (. Xing, and D. Jena

7/20/2020

Near-ideal reverse leakage current and practical maximum electric field in β-Ga2O3 Schottky barrier diodes

W. Li, D. Saraswat, Y. Long, K. Nomoto, D. Jena, and H. G. Xing

5/11/2020

Optical properties of cubic boron arsenide

B. Song, K. Chen, K. Bushick, K. A. Mengle, F. Tian, G. A. G. U. Gamage, Z. Ren, E. Kioupakis, and G. Chen

4/6/2020

Fighting Broken Symmetry with Doping: Toward Polar Resonant Tunneling Diodes with Symmetric Characteristics

J. Encomendero, V. Protasenko, F. Rana, D. Jena, and H. G. Xing

3/19/2020

Multiferroic LuFeO3 on GaN by molecular-beam epitaxy

J. Casamento, M. E. Holtz, H. Paik, P. Dang, R. Steinhardt, H. (. Xing, D. G. Schlom, and D. Jena

3/9/2020

Monolithically p-down nitride laser diodes and LEDs obtained by MBE using buried tunnel junction design

H. Turski, S. Bharadwaj, M. Siekacz, G. Muziol, M. Chlipala, M. Zak, M. Hajdel, K. Nowakowski-Szkudlarek, S. Stanczyk, H. Xing, D. Jena, and C. Skierbiszewski

2/16/2020

Enhanced injection efficiency and light output in bottom tunnel-junction light-emitting diodes

S. Bharadwaj, J. Miller, K. Lee, J. Lederman, M. Siekacz, H. (. Xing, D. Jena, C. Skierbiszewski, and H. Turski

2/3/2020

Boron arsenide heterostructures: lattice-matched heterointerfaces and strain effects on band alignments and mobility

K. Bushick, S. Chae, Z. Deng, J. T. Heron, and E. Kioupakis

1/16/2020

Molecular Beam Epitaxy Growth of Large‐Area GaN/AlN 2D Hole Gas Heterostructures

R. Chaudhuri, S. J. Bader, Z. Chen, D. Muller, H. G. Xing, and D. Jena

1/15/2020

Oxygen Incorporation in the Molecular Beam Epitaxy Growth of Sc_xGa_1−xN and Sc_xAl_1−xN

J. Casamento, H. G. Xing, and D. Jena

1/9/2020

Field-Plated Ga₂O₃ Trench Schottky Barrier Diodes With a BV²/$R_{\text{on,sp}}$ of up to 0.95 GW/cm²

W. Li, K. Nomoto, Z. Hu, D. Jena, and H. G. Xing

1/1/2020

GaN/AlN p-channel HFETs with Imax > 420 mA/mm and Similar to 20 GHz fT/fMAX in IEEE International Electron Devices Meeting (IEDM)

1/1/2020

Nitride LEDs and Lasers with Buried Tunnel Junctions

H. Turski, M. Siekacz, G. Muzioł, M. Hajdel, S. Stańczyk, M. Żak, M. Chlipała, C. Skierbiszewski, S. Bharadwaj, H. G. Xing, and D. Jena

12/5/2019

BAlGaN alloys nearly lattice-matched to AlN for efficient UV LEDs

L. Williams, and E. Kioupakis

12/2/2019

Thermal conductivity of crystalline AlN and the influence of atomic-scale defects

R. L. Xu, M. Muñoz Rojo, S. M. Islam, A. Sood, B. Vareskic, A. Katre, N. Mingo, K. E. Goodson, H. G. Xing, D. Jena, and E. Pop

11/12/2019

A polarization-induced 2D hole gas in undoped gallium nitride quantum wells

R. Chaudhuri, S. J. Bader, Z. Chen, D. A. Muller, H. G. Xing, and D. Jena

9/27/2019

Room-temperature stability of excitons and transverse-electric polarized deep-ultraviolet luminescence in atomically thin GaN quantum wells

D. Bayerl, and E. Kioupakis

9/23/2019

Route to High Hole Mobility in GaN via Reversal of Crystal-Field Splitting

S. Poncé, D. Jena, and F. Giustino

8/29/2019

Hole mobility of strained GaN from first principles

S. Poncé, D. Jena, and F. Giustino

8/29/2019

Quasiparticle band structure and optical properties of rutile GeO2, an ultra-wide-band-gap semiconductor

K. A. Mengle, S. Chae, and E. Kioupakis

8/23/2019

Unusual step meandering due to Ehrlich-Schwoebel barrier in GaN epitaxy on the N-polar surface

H. Turski, F. Krzyżewski, A. Feduniewicz-Żmuda, P. Wolny, M. Siekacz, G. Muziol, C. Cheze, K. Nowakowski-Szukudlarek, H. (. Xing, D. Jena, M. Załuska-Kotur, and C. Skierbiszewski

8/1/2019

Lattice-constant and band-gap tuning in wurtzite and zincblende BInGaN alloys

K. Greenman, L. Williams, and E. Kioupakis

8/1/2019

Wurtzite phonons and the mobility of a GaN/AlN 2D hole gas

S. J. Bader, R. Chaudhuri, M. F. Schubert, H. W. Then, H. G. Xing, and D. Jena

6/24/2019

Rotationally aligned hexagonal boron nitride on sapphire by high-temperature molecular beam epitaxy

R. Page, J. Casamento, Y. Cho, S. Rouvimov, H. G. Xing, and D. Jena

6/4/2019

Blue (In,Ga)N light-emitting diodes with buried n ⁺–p ⁺ tunnel junctions by plasma-assisted molecular beam epitaxy

Y. Cho, S. Bharadwaj, Z. Hu, K. Nomoto, U. Jahn, H. G. Xing, and D. Jena

5/31/2019

Polarization control in nitride quantum well light emitters enabled by bottom tunnel-junctions

H. Turski, S. Bharadwaj, H. (. Xing, and D. Jena

5/28/2019

Fin-channel orientation dependence of forward conduction in kV-class Ga₂O₃ trench Schottky barrier diodes

W. Li, K. Nomoto, Z. Hu, D. Jena, and H. G. Xing

5/23/2019

The new nitrides: layered, ferroelectric, magnetic, metallic and superconducting nitrides to boost the GaN photonics and electronics eco-system

D. Jena, R. Page, J. Casamento, P. Dang, J. Singhal, Z. Zhang, J. Wright, G. Khalsa, Y. Cho, and H. G. Xing

5/17/2019

Significant Phonon Drag Enables High Power Factor in the AlGaN/GaN Two-Dimensional Electron Gas

A. S. Yalamarthy, M. Muñoz Rojo, A. Bruefach, D. Boone, K. M. Dowling, P. F. Satterthwaite, D. Goldhaber-Gordon, E. Pop, and D. G. Senesky

5/15/2019

Bandgap narrowing and Mott transition in Si-doped Al0.7Ga0.3N

S. Bharadwaj, S. M. Islam, K. Nomoto, V. Protasenko, A. Chaney, H. (. Xing, and D. Jena

3/18/2019

Broken Symmetry Effects due to Polarization on Resonant Tunneling Transport in Double-Barrier Nitride Heterostructures

J. Encomendero, V. Protasenko, B. Sensale-Rodriguez, P. Fay, F. Rana, D. Jena, and H. G. Xing

3/13/2019

Rutile GeO2: An ultrawide-band-gap semiconductor with ambipolar doping

S. Chae, J. Lee, K. A. Mengle, J. T. Heron, and E. Kioupakis

3/11/2019

New physics in GaN resonant tunneling diodes

G. Xing, J. Encomendero, and D. Jena

3/1/2019

Impact of the stacking sequence on the bandgap and luminescence properties of bulk, bilayer, and monolayer hexagonal boron nitride

K. A. Mengle, and E. Kioupakis

2/1/2019

Band structure and carrier effective masses of boron arsenide: Effects of quasiparticle and spin-orbit coupling corrections

K. Bushick, K. Mengle, N. Sanders, and E. Kioupakis

1/14/2019

Vibrational and electron-phonon coupling properties of β-Ga2O3 from first-principles calculations: Impact on the mobility and breakdown field

K. A. Mengle, and E. Kioupakis

1/1/2019

Measurement of ultrafast dynamics of photoexcited carriers in β-Ga2O3 by two-color optical pump-probe spectroscopy

O. Koksal, N. Tanen, D. Jena, H. (. Xing, and F. Rana

12/17/2018

Gate-Recessed E-mode p-Channel HFET With High On-Current Based on GaN/AlN 2D Hole Gas

S. J. Bader, R. Chaudhuri, K. Nomoto, A. Hickman, Z. Chen, H. W. Then, D. A. Muller, H. G. Xing, and D. Jena

12/1/2018

Point defects and dopants of boron arsenide from first-principles calculations: Donor compensation and doping asymmetry

S. Chae, K. Mengle, J. T. Heron, and E. Kioupakis

11/19/2018

1230 V β-Ga2O3 trench Schottky barrier diodes with an ultra-low leakage current of <1 μA/cm2

W. Li, Z. Hu, K. Nomoto, Z. Zhang, J. Hsu, Q. T. Thieu, K. Sasaki, A. Kuramata, D. Jena, and H. G. Xing

11/12/2018

Breakdown mechanism in 1 kA/cm2 and 960 V E-mode β-Ga2O3 vertical transistors

Z. Hu, K. Nomoto, W. Li, Z. Zhang, N. Tanen, Q. T. Thieu, K. Sasaki, A. Kuramata, T. Nakamura, D. Jena, and H. G. Xing

9/17/2018

Enhancement-Mode Ga₂O₃ Vertical Transistors With Breakdown Voltage >1 kV

Z. Hu, K. Nomoto, W. Li, N. Tanen, K. Sasaki, A. Kuramata, T. Nakamura, D. Jena, and H. G. Xing

6/1/2018

Tuning Electrical and Thermal Transport in AlGaN/GaN Heterostructures via Buffer Layer Engineering

A. S. Yalamarthy, H. So, M. Muñoz Rojo, A. J. Suria, X. Xu, E. Pop, and D. G. Senesky

3/30/2018

Flexural resonance mechanism of thermal transport across graphene-SiO2 interfaces

Z. Ong, B. Qiu, S. Xu, X. Ruan, and E. Pop

3/19/2018

Room temperature microwave oscillations in GaN/AlN resonant tunneling diodes with peak current densities up to 220 kA/cm2

J. Encomendero, R. Yan, A. Verma, S. M. Islam, V. Protasenko, S. Rouvimov, P. Fay, D. Jena, and H. G. Xing

3/5/2018

Demonstration of AlGaN-delta-GaN QW by plasma-assisted molecular beam epitaxy for 260-nm ultraviolet light emitting diodes

C. Liu, K. Lee, S. M. Islam, H. Xing, D. Jena, and J. Zhang

2/23/2018

234 nm and 246 nm AlN-Delta-GaN quantum well deep ultraviolet light-emitting diodes

C. Liu, Y. K. Ooi, S. M. Islam, H. (. Xing, D. Jena, and J. Zhang

1/1/2018

BInGaN alloys nearly lattice-matched to GaN for high-power high-efficiency visible LEDs

L. Williams, and E. Kioupakis

11/20/2017

Spatially Resolved Thermometry of Resistive Memory Devices

E. Yalon, S. Deshmukh, M. Muñoz Rojo, F. Lian, C. M. Neumann, F. Xiong, and E. Pop

11/10/2017

New Tunneling Features in Polar III-Nitride Resonant Tunneling Diodes

J. Encomendero, F. A. Faria, S. . Islam, V. Protasenko, S. Rouvimov, B. Sensale-Rodriguez, P. Fay, D. Jena, and H. G. Xing

10/23/2017

Temperature-Dependent Thermal Boundary Conductance of Monolayer MoS₂ by Raman Thermometry

E. Yalon, B. Aslan, K. K. H. Smithe, C. J. McClellan, S. V. Suryavanshi, F. Xiong, A. Sood, C. M. Neumann, X. Xu, K. E. Goodson, T. F. Heinz, and E. Pop

10/20/2017

Deep-UV emission at 219 nm from ultrathin MBE GaN/AlN quantum heterostructures

S. M. Islam, V. Protasenko, K. Lee, S. Rouvimov, J. Verma, H. (. Xing, and D. Jena

8/28/2017

Effect of oxygen vacancies and strain on the phonon spectrum of HfO2 thin films

L. Gao, E. Yalon, A. R. Chew, S. Deshmukh, A. Salleo, E. Pop, and A. A. Demkov

6/8/2017

Energy Dissipation in Monolayer MoS2 Electronics

4/1/2017

Physics and polarization characteristics of 298 nm AlN-delta-GaN quantum well ultraviolet light-emitting diodes

C. Liu, Y. K. Ooi, S. M. Islam, J. Verma, H. (. Xing, D. Jena, and J. Zhang

2/13/2017