Xitong Sun

Xitong Sun

The University of Texas at Austin

Xitong Sun

M.S. student in Mechanical Engineering

Hey! Glad youā€™re here!

I study power electronics based on piezoelectric passive components with Prof. Ruochen Lu, and have worked on modeling and control of high-performance power converters with Prof. Yicheng Zhu.

I received my B.E. with Honors in Microelectronics in July 2025 at Southern University of Science and Technology (SUSTech), a young university established in 2010 in Shenzhen, China (a short story about SUSTech). During my undergraduate studies, I conducted research on MEMS-based gas sensors under the supervision of Prof. Fei Wang. In August 2025, I was proud to join the University of Texas at Austin as a member of the Longhorns and begin my M.S. studies in Mechanical Engineering.

I have experience in IC-level design and simulation (e.g., Cadence Virtuoso), device-level simulation (e.g., COMSOL Multiphysics), system-level design and prototyping (e.g., KiCad, PLECS, Code Composer Studio (CCS)), as well as cleanroom-based device fabrication.

I am seeking Ph.D. opportunities in Power Electronics for Fall 2027.

Please feel free to contact me at xitongsun@utexas.edu.

šŸ“ Research

Conductive-Silicon-Packaged Piezoelectric Resonators

Advised by Prof. Ruochen Lu Ā· UT Austin

A conductive-silicon package for LiNbO3 resonators, designed to improve power handling and heat dissipation while avoiding electrode breakdown.

  • Demonstrated capacitive excitation through Siā€“LN air gaps, retaining 95% of bare-LN Q and 99% of k2.
  • Fabricated Siā€“LNā€“Si prototypes using Auā€“Au, BCB, photoresist and Crystalbond bonding, and evaluated their effects on resonator performance.
  • Evaluated packaging effects on power handling and thermal performance under high-power excitation.
Layer structure of the Siā€“LNā€“Si packaged resonator.
Layer structure of the Siā€“LNā€“Si packaged resonator.
Measured frequency response of the packaged resonator; Q and coupling estimates are annotated.
Measured frequency response of the packaged resonator; Q and coupling estimates are annotated.

Vertically Stacked LiNbO3 Isolation Transformers

Advised by Prof. Ruochen Lu Ā· UT Austin

An LNā€“sapphireā€“LN transformer for mechanically coupled power transfer across an electrically insulating layer.

  • Simulated mode shapes and admittance spectra for 36Ā°, 128Ā° and 163Ā° Y-cut LN in COMSOL; optimized layer thicknesses for half-wavelength resonance.
  • Fabricated two-port prototypes and designed test PCBs with corner-fixed mounting and wire-bonded interconnects.
  • Characterization in progress: VNA-based resonance, Q and k2; nonlinearity, power handling, temperature coefficient of frequency and power-transfer efficiency.
Simulated displacement of the LNā€“sapphireā€“LN transformer.
Simulated displacement of the LNā€“sapphireā€“LN transformer.
Measured two-port admittance spectra of the transformer.
Measured two-port admittance spectra of the transformer.

Modeling and Control of Multiphase Buck Converters

Advised by Prof. Yicheng Zhu Ā· UT Austin

A modeling and simulation study of how feedback-control strategies affect multiphase buck dynamics and regulation.

  • Developed state-space averaged and small-signal models for converter dynamics and feedback-controller design.
  • Implemented voltage-mode, current-mode, COT and V2 control in PLECS, and assessed stability in the frequency domain and regulation in the time domain.
  • Compared voltage deviation, settling time and implementation complexity across control strategies.
Conceptual multiphase buck architecture. This schematic illustrates the research topic; it is not a simulation result.
Conceptual multiphase buck architecture. This schematic illustrates the research topic; it is not a simulation result.

MEMS Gas Sensor Arrays with Wafer-Level Material Patterning

Advised by Prof. Fei Wang Ā· SUSTech

Wafer-level fabrication and data-driven gas identification using multi-material MEMS sensor arrays.

  • Optimized a backside-etched microheater, reducing heating power by 25% relative to the frontside-etched design.
  • Developed multi-step photolithography to pattern multiple gas-sensing materials; fabricated arrays through lithography, deposition and etching.
  • Applied SVM models to sensor responses, achieving 100% classification accuracy and R2 ā‰„ 0.98 for concentration prediction on a test set.
Wafer-level fabrication and material-patterning process. See the Transducers 2025 paper below.
Wafer-level fabrication and material-patterning process. See the Transducers 2025 paper below.
Sensor response patterns and concentration prediction for ethanol and acetone. Results from the Transducers 2025 paper.
Sensor response patterns and concentration prediction for ethanol and acetone. Results from the Transducers 2025 paper.

šŸ“„ Publications

  1. MEMS Gas Sensor Arrays with Multilayer of Nanomaterials Patterned by Wafer-Level Photolithography Process, X. Sun, J. Li, T. Cheng, and F. Wang, Transducers 2025, Orlando, FL, USA.
  2. MEMS Gas Sensor with On-chip Electrospun Ru-SnOā‚‚ Nanospheres Patterned by Photolithography, J. Li, X. Sun, T. Cheng, and F. Wang, IEEE SENSORS 2024, Kobe, Japan.
  3. MEMS Acetone Gas Sensors with Eu-doped SnOā‚‚/Inā‚‚Oā‚ƒ Nanofibers Using Electrospinning and Lithography Patterning Technique, T. Cheng, J. Li, G. Niu, X. Sun, and F. Wang, IEEE SENSORS 2024, Kobe, Japan.
  4. MEMS Gas Sensors with Metal-Oxide Semiconductor Materials Patterned at Wafer-Level by Photolithography Technique, X. Liu, G. Niu, J. Li, Y. Zhuang, X. Sun, and F. Wang, IEEE SENSORS 2023, Vienna, Austria.

šŸ“š Course Projects

24 V to 48 V Synchronous Boost Converter Prototype

Jan. 2026 ā€“ Jun. 2026 Ā· Power Electronic Devices and Systems
Instructor: Prof. Yicheng Zhu

Built and tested a 250 W converter with 95.7% peak conversion efficiency.

  • Designed a four-layer PCB in KiCad, minimizing high-di/dt commutation and gate-drive loop areas.
  • Designed and built the power inductor; programmed a TI C2000 MCU for complementary PWM, dead time and synchronized ADC sensing.
  • Characterized switching waveforms, voltage/current ripple and load-dependent efficiency.

Synchronous Buck Converter Design with V2 Peak Control

Sep. 2025 ā€“ Nov. 2025 Ā· Power Management Integrated Circuits
Instructor: Prof. Alex Q. Huang

  • Designed and simulated a synchronous buck converter in Cadence Virtuoso, using PWM at high load and PFM at light load.
  • Integrated a ramp generator, comparator, compensation network, gate driver with dead-time control, and overcurrent and overvoltage protection.
  • Optimized transistor sizing and passive component dimensions to reduce the design footprint.

Technical experience

IC design: Cadence Virtuoso Ā· Device simulation: COMSOL Multiphysics Ā· Systems: KiCad, PLECS, Code Composer Studio Ā· Fabrication: photolithography, deposition, etching and wafer bonding.

šŸ“– Education

  • The University of Texas at Austin
    M.S. in Mechanical Engineering Ā· Aug. 2025 ā€“ Present
  • Southern University of Science and Technology
    B.E. with Honors in Microelectronics Ā· Sep. 2021 ā€“ Jul. 2025
  • University of California, Berkeley
    Summer Session Ā· Jun. 2023 ā€“ Aug. 2023

šŸŽ– Honors and Awards

  • 2025, 2026 Ā· Britton R. Birmingham Graduate Fellowship in Engineering, UT Austin
  • 2025 Ā· Outstanding Graduate / Outstanding Undergraduate Thesis, SUSTech
  • 2024 Ā· National Scholarship, Ministry of Education of China
  • 2023, 2024 Ā· First-Class Scholarship, SUSTech

šŸ”„ News

  • 2026.03 Ā· Joined Prof. Ruochen Luā€™s RAM Lab at UT. Grateful for this opportunity!
  • 2025.08 Ā· Started my M.S. studies in Mechanical Engineering at The University of Texas at Austin!
  • 2025.08 Ā· Awarded the Britton R. Birmingham Graduate Fellowship in Engineering at The University of Texas at Austin.
  • 2025.07 Ā· Received my B.E. degree from SUSTech. Deeply grateful to Prof. Fei Wang and all members of the MEMS Group. I will always cherish my wonderful time at SUSTech.
  • 2025.06 Ā· Received the Outstanding Undergraduate Graduate and Outstanding Undergraduate Thesis awards from Southern University of Science and Technology.
  • 2025.06 Ā· My paper on MEMS gas sensor arrays was presented at Transducers 2025 in Orlando, Florida.
  • 2024.12 Ā· Awarded the National Scholarship!
  • 2024.10 Ā· My paper on MEMS gas sensors was presented at IEEE SENSORS 2024 in Kobe, Japan.

šŸ˜Ž Play Hard

I graduated from Southern University of Science and Technology in 2025. I am deeply grateful to all the teachers, friends and family members who supported me along the way. SUSTech gave me countless precious memories, which I will keep in my heart forever.

Memories from SUSTech (1).
Memories from SUSTech (2).
Memories from SUSTech (3).
Memories from SUSTech (4).

I'm also a big fan of classical music. I spent four joyful years with the SUSTech Philharmonic, and one year as orchestra president. I participated in more than 20 performances. I also enjoy attending concerts and have heard memorable performances by the San Francisco Symphony Orchestra, New York Philharmonic, National Symphony Orchestra, Austin Symphony Orchestra, and West-Eastern Divan Orchestra. My favorite piece is Sibeliusā€™s Violin Concerto in D minor.

SUSTech Philharmonic performance.
Memories with the orchestra.
A night of classical music.

I also love traveling and exploring different landscapes. Yosemite is my favorite national park.

From my travels (1).
From my travels (2).
Yosemite National Park.
From my travels (4).
From my travels (5).
From my travels (6).