Projects

GaN Super-Heterojunction Power Switches

Today’s GaN power switches, with typical voltage rating of 100~900 V, have demonstrated superior performance over the incumbent Si technology. We are developing the GaN super-heterojunction device structure to extend the voltage handling up to 10 kV and down to sub-100 V.

GaN Super-Heterojunction FETs With 10-kV Blocking and 3-kV Dynamic Switching https://ieeexplore.ieee.org/abstract/document/10379549

M. Sadek, “Conduction and Breakdown Mechanisms of Isolation in Gallium Nitride Devices,” Lester Eastman Conference, 8, Aug. 2023, University of Illinois, Chicago, Illinois.

R. Guan, “AlGaN/GaN Double-Channel MOS Gated Schottky Barrier Diode with Low Reverse Leakage Current,” Lester Eastman Conference, 8, Aug. 2023, University of Illinois, Chicago, Illinois.

J. Kemmerling, R. Guan, M. Sadek, Y. Xiong, J. Song, S. Han, R. Chu, “Experimental Demonstration of GaN Super-Heterojunction MOSFETs with 3 kV Dynamic Switching and 10 kV Blocking,” GOMAC Tech 2023, 23 Mar, 2023, San Diego, CA.

Impact of Charge Balance on Static and Dynamic Characteristics of GaN Super-Heterojunction Schottky Barrier Diodes https://ieeexplore.ieee.org/abstract/document/9744108

High-Temperature Static and Dynamic Characteristics of 4.2-kV GaN Super-Heterojunction p-n Diodes https://ieeexplore.ieee.org/abstract/document/9734234

8.85-kV/0.72-A Charge-Balanced GaN Super-Heterojunction Schottky Barrier Diode https://ieeexplore.ieee.org/abstract/document/9798119

12.5 kV GaN Super-Heterojunction Schottky Barrier Diodes https://ieeexplore.ieee.org/abstract/document/9547414

Study of interface trap density of AlOxNy/GaN MOS structures https://pubs.aip.org/aip/apl/article/119/12/122105/40334

GaN Super-Heterojunction Schottky Barrier Diode with Over 10 kV Blocking Voltage https://ieeexplore.ieee.org/abstract/document/9420906

Experimental Demonstration of Charge- Balanced GaN Super-Heterojunction Schottky Barrier Diode Capable of 2.8 kV Switching https://ieeexplore.ieee.org/abstract/document/9217445

Design of GaN/AlGaN/GaN Super-Heterojunction Schottky Diode https://ieeexplore.ieee.org/abstract/document/8932621

High- Q GaN Varactors for mm-Wave Applications: A Physics-Based Simulation Study https://ieeexplore.ieee.org/abstract/document/8811826

Characteristics of P-channel GaN MOSFET up to 300 °C https://ieeexplore.ieee.org/abstract/document/9046423

Radiation Effects of GaN Electronics

The GaN electronics is expected play a key role in supporting space missions. It is therefore important to understand and predict radiation effects of GaN electronics. We are a part of a Multidisciplinary University Research Initiative (MURI) team (https://sites.psu.edu/redesign/), pursuing a holistic understanding of radiation effects in GaN electronic devices at the electronic, atomic, and device levels.

High-Temperature GaN Transistors

High-temperature electronics are needed by many systems: oil-and-gas, geothermal, automotive, and turbine engine. GaN transistor technology offers a unique opportunity to achieve high operating-temperature, large bandwidth, and high-power handling simultaneously. We are developing GaN device structures and processes to realize a GaN amplifier operating at above 800 ºC.

High-Temperature Static and Dynamic Characteristics of 4.2-kV GaN Super-Heterojunction p-n Diodes https://ieeexplore.ieee.org/abstract/document/9734234

Characteristics of P-channel GaN MOSFET up to 300 °C https://ieeexplore.ieee.org/abstract/document/9046423

Exploring benefits of composition grading for forward-IV characteristics of In1−xGaxAs LEDs for cryogenic applications https://pubs.aip.org/aip/jap/article/128/17/175701/1080173

Integrated GaN Electronics

Speed of today’s GaN power switches is largely limited by parasitics between discretely packaged components. We are exploring chip-scale integration of power switch, gate driver, and optocoupler, unleashing the full potential of GaN’s fast-switching capability.

Y. Xiong, R. Chu, “Evaluation and Optimization of GaN Unipolar MOS Logic Circuits (student)”, Compound Semiconductor Week 2022, 2022, University of Michigan, Ann Arbor, Michigan. Oral Presentation.