Physical Sensors & Devices

We aim to develop a family of autonomous silicon-based robotic insects that integrate actuation, computation, and power within a single platform. A silicon-on-insulator (SOI) device serves as the foundation, enabling electrostatic actuators that drive silicon linkages fabricated directly in the device layer. Electrostatic actuation provides a key advantage at the microscale, offering low power consumption suitable for energy harvesting and autonomous operation. Computation and communication are enabled by the Single Chip Micro Mote (SCuM, BPN803), while a Zappy2 chip with integrated solar...

Chemiresistive gas sensors based on semiconductor metal oxides, such as tin oxide (SnO₂), play a critical role in detecting toxic gases and monitoring pollution in industrial and environmental applications. Siloxanes, organic compounds that contain silicon and oxygen atoms and are widely used in personal care products, are commonly present in various environments. The presence of these compounds can significantly degrade sensor performance by modifying the oxide surface, altering its gas adsorption properties, and reducing both sensitivity and selectivity in gas sensing. To address this...

We have been developing sweat sensors to analyze physiological and metabolic health information, such as sweat rate, glucose levels, pH, and various electrolytes, from any surface on the body surface where sweat glands are present. However, the stiff sweat sensors developed so far struggle to detect subtle signal changes, especially on soft skin. This is due to a mechanical mismatch between the rigid sweat sensor and the pliable skin, which can lead to motion artifacts and delamination of the patch from skin. Specifically, the stiff sensor cannot easily stretch along with the...

Infrared detection and imaging have a wide range of applications in thermal imaging, optical communication, gas sensing, and night vision. Currently, detection in the short-wave infrared (SWIR, 1 – 3 um) predominantly utilizes semiconducting materials such as single-crystalline germanium (Ge) and III-V semiconductors such as indium gallium arsenide phosphide (InGaAsP). The epitaxial growth of these materials often entails sophisticated methods that require high process temperatures and careful lattice matching with the substrate, making device fabrication costly and often poorly scaled....