Physical Sensors & Devices

Research that includes:

  • Silicon MEMS actuators: comb, electro-thermal, and plastic deformation
  • Precision electronic sensing and measurements of capacitive, frequency, and coulombic MEMS variables
  • Structures and architectures for gyroscopes, accelerometers, micro strain gauges for direct application to rigid structures e.g., steel, and levitated MEMS

BPN743: Highly Responsive PMUTs for Volumetric Environmental Monitoring and Multimodal Tactile Sensing

Megan Teng
Peggy Tsao
Hanxiao Liu
Yande Peng
2026

This work presents a unified MEMS platform utilizing Piezoelectric Micromachined Ultrasonic Transducers (PMUTs) for dual-mode sensing: continuous volumetric indoor temperature monitoring and multimodal tactile force sensing. By leveraging ultrasonic Time-of-Flight (ToF) and profile scanning, we demonstrate two critical advancements for autonomous systems. First, at the macro-scale, a networked PMUT grid enables "volumetric" temperature monitoring across a 5m range, outperforming traditional pointwise sensors by detecting global and local thermal events for energy-efficient HVAC control....

Scalable Multiplexed Machine Learning Gas Sensor Chips for Food Classification

Carla Bassil
Kichul Lee
Xun Liao
Divya N. Kashyap
Yifei Zhan
Theodorus Jonathan Wijaya
Edward Hester
Minhyun Kim
Il-Doo Kim
Inkyu Park
Ali Javey
2026

Multiplexed gas sensor arrays combined with machine learning have unlocked previously inaccessible applications for scent-based sensing. Current platforms are limited by overlapping sensing materials with similar compositions, leading to highly correlated responses, or multistep deposition processes that hinder scalability. In this work, we developed a 16-element monolithic chip with fully distinct sensing layers, enabling a truly heterogeneous array. The system consists of highly sensitive carbon nanotube field effect transistors that are functionalized through a single-step...

20.3 An RFID-inspired One-step Packaged Multi-mode Bio-analyzer with Vacuum Microfluidics for Point-of-Care Diagnostics

Yan-Ting Hsiao
Ya-Chen (Justine) Tsai
Wei Foo
Hung-Yu Hou
Yun-Chun Su
Yueting Lily Li
Jun-Chau Chien
2025

Current clinical practice for detecting low-concentration molecular biomarkers requires sending samples to centralized labs, leading to high costs and delays (Fig. 20.3.1). Recent developments in molecular diagnostics thus aim to enable point-of-care (POC) detection directly at or near the patient's location [1]–[2]. The most successful POC technology to date is the paper-based lateral-flow assay (LFA) [3]–[4]. Examples include pregnancy tests that sense progesterone and SARS-CoV-2 rapid antigen tests. However, paper-based assays generally provide binary results or limited quantitative...

Extension-Enhanced Wavelet Decomposition: a Noise and Background Resilient Square-Wave Voltammogram Signal-Processing Technique for Electrochemical Aptamer-Based Biosensing In Vivo

Ya-Chen (Justine) Tsai
Hyongsok Tom Soh
Jun-Chau Chien
2026

Electrochemical aptamer-based (E-AB) sensors undergo structure-switching upon target binding, making them well-suited for in vivo continuous monitoring of biomolecules with high sensitivity and selectivity. Although square-wave voltammetry (SWV) is the most widely used analytical technique for probing the states of E-AB sensors, precise signal extraction from SWVs acquired during in vivo measurements remains challenging. The difficulty arises due to additive electronic and chemical noise, as well as varying background currents caused by factors such as the reduction of dissolved oxygen,...

A One-Step-Packaged CMOS/Microfluidics Wireless Bio-Analyzer for Point-of-Care Diagnostics

Yan-Ting Hsiao
Wei Foo
Hung-Yu Hou
Yun-Chun Su
Shu-Yan Chuang
Jun-Chau Chien
2025

Point-of-care (POC) diagnostics can revolutionize current medicine by enabling rapid, at-home molecular testing for early disease detection and treatment monitoring. Though several mainstream POC technologies exist, such as paper-based lateral flow assays (LFAs) and microfluidic cartridges, they either lack quantification capability or require a dedicated reader for electrical readout. Miniaturization enabled by high-performance CMOS integrated circuits (ICs) has been proposed to address these limitations, but complex CMOS/microfluidics packaging due to the need for electrical connections...

High Velocity Diamond Disk Resonator

William Dong
Hung-Yu Chen
Kevin H. Zheng
Xintian Liu
Clark T.-C. Nguyen
2026

The high fracture strength of polydiamond has enableda 167-MHz polydiamond disk resonator with a self-aligned polysilicon stem anchor to attain a velocity of 83 m/s, which is 56 times larger than the typical ~1.5 m/s [1] velocity employed by MEMS based sensors, such as gyroscopes. The key to this performance is the use of hot-filament chemical vapor deposited (HFCVD) diamond structural material with a fracture strength from 50-120 GPa [2] many times larger than the ~2.6 GPa average of polysilicon [3]. The resonator design herein further concentrates energy in the diamond resonator...

BPNX1061: 3D Imaging Using PMUTs (New Project)

Nikita Lukhanin
Divij Muthu
Mostafa Sedky
Megan Teng
Tofic Esses
Linda Liu
Suraj Chamakura
Ryan Johnson
Chun-Ming Chen
2026

We have used PMUTs for 3D imaging. based on a 4×4 bimorph, pinned dual-electrode PMUTs array with the transmission beamforming scheme. This project advances the ultrasound-based imaging technique by using the compressed sensing scheme. The goal is to achieve 3D imaging with a low number of transducers and minimum computation for various applications in robotics, wearable electronics, autonomous navigation, and medical diagnostics.

Project is currently funded by: Member Fees

BPNX1022: Multiplexed Gas Sensors

Carla Bassil
Kichul Lee
2026

Gas sensing has long been an area of academic and industrial interest. However, state of the art sensors still lack selectivity and sensitivity when it comes to differentiating gases of similar compositions. In this work, we explore methods to create multiplexed gas sensors that can differentiate these mixtures with high accuracy and long-term stability.

Project is currently funded by: Federal

Ultra-Sensitive Nanosensor for Rapid Detection of PFAS in Simulated Drinking Water

Nikita Lukhanin
Keming Bai
Mia Wang
Declan M. Fitzgerald
Grigory Tikhomirov
Liwei Lin
2026

Per- and polyfluoroalkyl substances (PFAS) are a class of persistent synthetic compounds, often called “forever chemicals,” that pose a significant threat to public health and the environment. Standard detection methods primarily rely on liquid chromatography and mass spectrometry [1], which is expensive, time-intensive, and requires trained personnel and laboratory infrastructure. While emerging approaches using metal-organic frameworks (MOFs), molecularly imprinted polymers, and lateral flow assays have been explored, they have yet to provide a solution that simultaneously offers part-...

3D Imaging via Four PMUT Receivers by Compressed Sensing

Nikita Lukhanin
Divij Muthu
Chaoying Gu
Megan Teng
Kamyar Behrouzi
Chun-Ming Chen
Laura Waller
Liwei Lin
2026

We have successfully demonstrated three-dimensional (3D) ultrasound imaging via compressed sensing using piezoelectric micromachined ultrasonic transducers (pMUTs). This work reports the first experimental demonstration of compressed sensing with pMUTs, achieving 3D image reconstruction near the acoustic wavelength limit by only four receiving elements. Pseudo-random transmission signatures were encoded through frequency and delay modulation to enable high-fidelity reconstruction with a peak signal contrast of 28.7 dB. A 16-element lithium-niobate pMUT array operating at a resonant...