Xingyu Zhou

Researcher on GaN Electronics

I am a researcher working on the development of wide-bandgap (WBG) GaN/GaO high-voltage power devices.

👨‍🎓 Biography

• Power device design of the wide-bandgap semiconductors (GaN, SiC, and Ga2O3) with high breakdown voltage, low switching losses, and high frequency, as well as the research on reliability and failure mechanism.

• Micro-/Nano-fabrication of GaN HEMTs and SiC/Ga2O3 MOSFET, as well as the wafer growth and material characterization.

• Converter circuit design of power electronics converter driven by wide-bandgap power devices, especially the GaN/SiC/Ga2O3 power integrated circuit (IC).

• Applications of WBG-powered converter in the electric car, renewable energy, 5G and 6G communication, and high voltage direct current transmission.

👨‍💻 Research Experience

Magnetosensory Power Devices based on AlGaN/GaN Heterojunctions for Interactive Electronics

• Designed a novel magnetosensory power device based on AlGaN/AlN/GaN heterojunction. Its output power can be significantly modulated by the external magnetic field.

• Fabricated the device with micro-nano processes from epitaxial wafers. The 2DEG concentration is 1.2E13/cm², and the maximum output power density reaches 8.6 KW/cm². Under the external magnetic field of 0 - 400 mT, the output power density of MPD increases from 1.804 KW/cm² to 1.894 KW/cm² at Vgs = -5 V.

• This work has been published in the peer-reviewed journal Advanced Electronic Materials funded through National Natural Science Foundation and forms part of my master’s thesis with a grade of A.

Modeling and Simulation of Gallium Nitride Power MEMS Devices

• Development of a 1-D self-consistent Quantum Mechanical AlGaN/GaN MEMS devices simulator using MATLAB and COMSOL Multiphysics based on the Schrödinger-Poisson equation.

• Simulate the modulation characteristics of 2DEG concentration, carrier concentration distribution, and energy band of the devices by the external magnetic field/strains.

• The simulator provides theoretical guidance for the research of GaN MEMS power devices and has been successfully applied to the design of Magnetosensory Power Devices and Strain-Controlled Power Devices.

• This work forms part of my master’s thesis with a grade of A.

Portable USB Charger Supporting Bidirectional Power Flow

• Designed a bidirectional DC/DC SEPIC converter to interface a lithium-polymer battery to a USB device with 94.6% static efficiency, which can supply 5 V at 2 A and 20 V at 3 A and charge the battery at 60 W from a 20 V USB source.

• Designed the magnetic inductors to minimize core size and weight, and verified them with the LTspice saturating inductor model.

• Designed the PWM voltage feedback control system with an averaged circuit model and verified the closed-loop system to meet load current transient requirements.

• This capstone project forms the practical portion of the Power Electronics Specialization at the University of Colorado Boulder, earning the specialization certificate with an average score of 95/100.

Strain-Controlled Power Devices as Inspired by Human Reflex

• Designed a novel strain-controlled power device based on AlGaN/AlN/GaN heterojunction. Its output power can be significantly modulated by external strains.

• Fabricated the device with micro-nano processes from epitaxial wafers. The 2DEG concentration is 1.19E13/cm^2. Under the external strain of 0 - 16 mN, the maximum output power density of SPD increases from 2.30 KW/cm^2 to 2.72 KW/cm^2 at Vgs = 1 V.

• This work has been published in the peer-reviewed journal Nature Communications funded through National Natural Science Foundation and forms part of my master’s thesis with a grade of A.

Piezotronic Effect Modulated Flexible AlGaN/ GaN High-Electron-Mobility Transistors

• Developed a wet etching wafer-scale substrate transfer technology to fabricate the flexible AlGaN/GaN HEMT arrays from rigid Si substrates. The 2DEG concentration is 1.15E13/cm^2, and the maximum output current density and transconductance reach 290 mA/mm^2 and 40 mS/mm respectively.

• Development of a 1-D self-consistent Quantum Mechanical flexible AlGaN/GaN HEMT devices simulator using MATLAB and COMSOL Multiphysics based on the Schrödinger-Poisson equation.

• This work has been published in the peer-reviewed journal ACS Nano funded through National Natural Science Foundation.

Switched-Inductor-Capacitor-Based Dual-Switch High-Boost DC-DC Converter

• Designed a new topology of the boost converter with high voltage gain and high efficiency. The maximum voltage gain reaches 50 with steady-state efficiency near 95% (without considering switching losses).

• Performed the DC and AC analysis using the state-space averaging method and small-signal analysis to model steady-state losses as well as the PWM voltage feedback control system and compensator.

• Verified the static electrical characteristics and transient behavior under input/load disturbances of the converter using Synopsys Saber and MATLAB Simulink.

• This work forms my bachelor’s thesis with a grade of 85/100.

🎓 Education

University of Chinese Academy of Sciences

Nanjing University of Aeronautics and Astronautics

ResearchGate

Google Scholar

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