RESEARCH
A research line that runs from a Berkeley thesis on a fingerprint sensor-on-a-chip to products in three markets. Papers, patents, and what each one was actually for.
MICROSCOPIC HARDWARE
RESEARCH
Piezoelectric micromachined ultrasonic transducers are small, cheap, and weak. Almost every interesting problem in this field is really a question about what the circuit has to do to make a weak transducer useful — and about designing the two together rather than throwing a finished transducer over the wall to a circuit designer.
Getting enough acoustic energy out of a piezo element means high voltage, and high voltage on the same die as a microvolt-sensitive receiver means the two must be kept apart in time, in space, and in the supply network. Steering that energy — transmit beamforming from an array — is what turns a proximity sensor into an imager.
Sensor, analog front end, and processor on one die. The payoff is not area, it is that the parasitic between the transducer and the first amplifier goes away, which is often the thing that sets the noise floor of the whole system.
A sensor that must run for years on a coin cell, or wake a car door in milliseconds, is a duty-cycling problem before it is a circuit problem. Precise time and frequency measurement is what buys back the accuracy that aggressive duty cycling costs.
From the papers themselves.
MICROSCOPIC HARDWARE
ULTRASONIC IMAGING
ACOUSTIC MEASUREMENT
Schematic illustration
MEMS + CMOS
Schematic illustration
ACOUSTIC PROPAGATION
Schematic illustration
Published pressure-field simulation
TRANSMIT BEAMFORMING
Schematic illustration
Published beam profile
PUBLICATIONS
Y. Lu, H.-Y. Tang, S. Fung, Q. Wang, J. M. Tsai, M. Daneman, B. E. Boser, D. A. Horsley
Applied Physics Letters, 106(26), 2015
Cited 300 times (Google Scholar, 2026-08-16)
50 mV-input batteryless boost converter for thermal energy harvesting
P.-S. Weng, H.-Y. Tang, P.-C. Ku, L.-H. Lu
IEEE Journal of Solid-State Circuits, 48(4), 2013
Cited 252 times (Google Scholar, 2026-08-16)
Monolithic ultrasound fingerprint sensor
X. Jiang, Y. Lu, H.-Y. Tang, J. M. Tsai, E. J. Ng, M. J. Daneman, B. E. Boser, D. A. Horsley
Microsystems & Nanoengineering, 3(1), 17059, 2017
Cited 194 times (Google Scholar, 2026-08-16)
X. Jiang, H.-Y. Tang, Y. Lu, E. J. Ng, J. M. Tsai, B. E. Boser, D. A. Horsley
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2017
Cited 183 times (Google Scholar, 2026-08-16)
3-D ultrasonic fingerprint sensor-on-a-chip
H.-Y. Tang, Y. Lu, X. Jiang, E. J. Ng, J. M. Tsai, D. A. Horsley, B. E. Boser
IEEE Journal of Solid-State Circuits, 51(11), pp. 2522-2533, 2016
Cited 182 times (Google Scholar, 2026-08-16)
3D ultrasonic rangefinder on a chip
R. J. Przybyla, H.-Y. Tang, A. Guedes, S. E. Shelton, D. A. Horsley, B. E. Boser
IEEE Journal of Solid-State Circuits, 50(1), pp. 320-334, 2015
Cited 181 times (Google Scholar, 2026-08-16)
Y. Lu, H.-Y. Tang, S. Fung, B. E. Boser, D. A. Horsley
Journal of Microelectromechanical Systems, 25(1), 2016
Cited 139 times (Google Scholar, 2026-08-16)
12.1 3D ultrasonic gesture recognition
R. J. Przybyla, H.-Y. Tang, S. E. Shelton, D. A. Horsley, B. E. Boser
IEEE International Solid-State Circuits Conference (ISSCC), pp. 210-211, 2014
Cited 136 times (Google Scholar, 2026-08-16)
PATENTS
Ultrasonic sensing, touch, force, and the transducer drive behind them.
Force-measuring and touch-sensing integrated circuit device
US 11,725,993 · piezo force
2023
Ultrasonic touch detection and decision
US 11,500,494 · ultrasound touch
2022
Operating a fingerprint sensor comprised of ultrasonic transducers
US 11,288,891 · fingerprint
2022
Miniature ultrasonic imaging system
US 10,820,888 · imaging
2020
Ultrasonic touch and force input detection
US 10,775,938 · ultrasound touch
2020
Ultrasonic touch sensor and system
US 10,719,175 · ultrasound touch
2020
Ultrasonic touch feature extraction
US 10,585,534 · ultrasound touch
2020
US 10,430,631 · fingerprint
2019
Superpixel array of piezoelectric ultrasonic transducers for 2-D beamforming
US 10,139,479 · beamforming
2018
Three-port piezoelectric ultrasonic transducer
US 10,001,552 · transducer
2018
Active beam-forming technique for piezoelectric ultrasonic transducer array
US 9,995,821 · beamforming
2018
36 granted US patents and 14 pending applications. Full portfolio on Google Patents
AWARDS
Lewis Winner Award for Outstanding Paper
IEEE International Solid-State Circuits Conference · for “3D Ultrasonic Fingerprint Sensor-on-a-Chip”
2016
Predoctoral Achievement Award
IEEE Solid-State Circuits Society
2015
Outstanding Student Paper Award
IEEE International Conference on Micro Electro Mechanical Systems
2017
EDUCATION
Ph.D., Electrical Engineering and Computer Sciences
University of California, Berkeley · Bernhard Boser's group. Thesis work on piezoelectric micromachined ultrasonic transducers and the integrated circuits that drive and read them, culminating in a 3-D ultrasonic fingerprint sensor-on-a-chip.
2012–2016
B.S., Electrical Engineering
National Taiwan University
2007–2011
ABOUT
Hao-Yen Tang is co-founder and CTO of UltraSense Systems, San Jose. He received the B.S. in Electrical Engineering from National Taiwan University and the Ph.D. in Electrical Engineering and Computer Sciences from the University of California, Berkeley, where he worked in Bernhard Boser's group on piezoelectric micromachined ultrasonic transducers and the integrated circuits that drive and read them. His thesis work on a 3-D ultrasonic fingerprint sensor-on-a-chip received the 2016 ISSCC Lewis Winner Award for Outstanding Paper and became the basis of a commercial fingerprint sensor product line. His research interests are integrated circuits for physical sensing: PMUT and piezoelectric transducer interfaces, high-voltage pulsers and transmit beamforming, monolithic sensor-on-CMOS integration, and low-power sensing systems-on-chip.
CONTACT
Tell us your goal, what you have today, and the engineering workflow you want to improve. Whether it is a chip, a board, a device, or a creative object, email us to start the conversation.
info@ponchiai.comFounder on LinkedInGoogle ScholarGoogle Patents
