Frontiers of Materials Award Symposium: Ultra-Wide Bandgap Materials and Heterostructures for Next Generation Power, RF and Quantum Applications: Ultra-Wide Bandgap Materials and Heterostructures for Next Generation Power, RF and Quantum Applications
Sponsored by: TMS Functional Materials Division, TMS: Nanomaterials Committee, TMS: Thin Films and Interfaces Committee
Program Organizers: Yuji Zhao, Rice University
Tuesday 2:30 PM
March 21, 2023
Room: Aqua 309
Location: Hilton
Session Chair: Yuji Zhao, Rice University
2:30 PM Keynote
Ultrawide Bandgap Materials: Properties, Synthesis and Devices: Yuji Zhao1; 1Rice University
Ultrawide bandgap (UWBG) materials such as diamond, Ga2O3, BN and AlN, are a new class of semiconductors that possess a wide range of attractive properties, including very large bandgap, high critical electric field, high carrier mobility and chemical inertness. Due to these outstanding characteristics, UWBG materials are promising candidates to enable high-performance devices for RF and power electronics, ultraviolet photonics, quantum sensing and quantum computing applications. Despite their great potential, the research of UWBG semiconductors is still at a nascent stage and represents a challenging interdisciplinary research area of physics, materials science and devices engineering. In this talk, I will give an overview on the material properties, synthesis methods and device applications of UWBG semiconductors including diamond, Ga2O3, h-BN and AlN. I will also give a brief introduction of the invited speakers and their leading work in the field.
2:55 PM Invited
Epitaxial Growth of c-BN on Diamond and Strategies for Electronic Applications: Avani Patel1; Saurabh Vishwakarma1; Ali Ebadi Yekta1; Jesse Brown1; David Smith1; Robert Nemanich1; 1Arizona State University
Cubic boron nitride (c-BN) is an ultra-wide bandgap semiconductor with properties appropriate for high power, high frequency electronics for extreme environments (high temperature, high radiation, and corrosive environments). The 6.4 eV bandgap of c-BN projects a breakdown field > 12 MV/cm. Moreover, n-type doping with S and Si (~0.3eV) and p-type doping with Be and Mg (~0.24 eV) have been demonstrated. The measured electron mobility of 825 cm2/V-s agree reasonably with theoretical values of 956 to 1680 cm2/V-s. In this talk, I will discuss our recent research efforts on epitaxial c-BN on diamond structures using ECR plasma enhanced CVD. The 150 nm thick c-BN films grown on single crystal diamond substrates are stable against delamination. The potential of epitaxial c-BN for different device configurations will be also discussed. Acknowledgement: Financial support by DOE through the ULTRA EFRC DE-SC0021230 (interface characterization) and the NSF DMR-2003567 (c-BN growth chemistry).
3:20 PM Invited
Gallium Oxide Semiconductors: Recent Progress and Future Prospective: Huili Grace Xing1; 1Cornell University
It’s of little surprise that there has been a consistent drive toward the use of wider bandgap materials for power electronics. After all, the wider the bandgap, the greater the breakdown field, opening the door to making devices with a higher breakdown voltage for the same material thickness. However, nature is not always that generous. Typically, a move to a wider bandgap is accompanied by more challenging doping, along with difficulty in making high-quality native substrates. Judged in these terms, Ga2O3 appears to offer a sweet spot beyond SiC and GaN. One of the most promising forms of Ga2O3 is its b-phase, which has a bandgap of 4.5-4.7 eV. In this talk, I will reflect on our efforts in researching on Ga2O3 based power devices. Acknowledgement: AFOSR FA9550-17-1-0048, NSF DMREF 1534303, and AFOSR FA9550-18-1-0529; performed in part at Cornell NanoScale Facility, an NNCI member supported by NSF Grant NNCI-2025233.
3:45 PM Invited
Nanoscale Engineering of III-Nitride Heterostructures for High Efficiency UV Optoelectronics and Quantum Photonics: Zetian Mi1; 1University of Michigan
We present an overview of some recent advances of nanoscale engineering of III-nitride heterostructures that are relevant for the development of high efficiency ultraviolet optoelectronic and quantum photonic devices. We show that relatively efficient p-type conduction of AlN and Al-rich AlGaN can be achieved in nearly dislocation-free nanostructures, or through in situ Fermi-level control during the growth of epilayers. High luminescence emission efficiency in the deep UV can be realized by exploiting strong quantum confinement of charge carriers, through either the formation of quantum dot-like nanoclusters or monolayer quantum wells. We further report on the first demonstration of fully epitaxial ferroelectric nitride semiconductors, including ScAlN and ScGaN, which can exhibit significantly enhanced electrical, piezoelectric, as well as linear and nonlinear optical properties. The recent advances of ScAlN integrated quantum photonics, including waveguides, ring resonators, and modulators, will be discussed.
4:10 PM Break
4:30 PM Invited
AlN-based Microelectronics for Extreme High Temperature Environments: Savannah Eisner1; 1Stanford University
Due to excellent electrical and thermal properties, aluminum nitride (AlN)-based microelectronics have gained interest for extreme environment sensing and RF applications in the space, energy, defense, and automotive industries. Extreme space applications for AlN technology include uncooled telecommunications for robotic exploration of hot planetary bodies like Venus, which would significantly increase mission length and scientific agenda. Yet despite successful demonstration of AlN semiconductor technology at 1000°C in vacuum, lingering challenges remain to achieve reliable device operation at ultra-high temperatures. In this talk, advances in techniques to mitigate high temperature performance instability, such as the development of novel contact metallization schemes, will be discussed. Recent promising developments in high-temperature capable solid-state two-dimensional electron gas (2DEG) devices and piezoelectric MEMS resonators for temperatures up to 600°C will be presented. Finally, the future landscape of AlN and other UWBG microelectronics for extreme high temperature space and terrestrial applications will be discussed.
4:55 PM Invited
Quantum Technologies with Diamond: Shuo Sun1; 1University of Colorado Boulder
In this talk, I will review recent progress in using diamond for different quantum applications. I will discuss the challenges working with diamond, and present our new hybrid integration approach for boosting the scalability of quantum devices in diamond.