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

BPN388: Micro Autonomous Air Vehicles

Ankur Mehta

This project considers the design and implementation of a guidance and control system for small scale autonomous air vehicles, in particular helicopters. A two gram inertial navigation unit has been designed and built for this purpose, using a three axis angular rate sensor and three axis accelerometer for trajectory measurements, along with a microprocessor and 2.4 GHz 802.15.4 radio. A smart IR camera is used to determine localization information. This extremely low mass wireless enabled sensor mote can be used as a platform for two-fist sized autonomous vehicles, and this system...

BPN539: Micromechanically-Enhanced Magnetoresistive Sensors

Gerardo Jaramillo
Andre Guedes

Magnetoresistive (MR) sensors are highly sensitive magnetic field sensors but suffer from large 1/f noise. We have developed a new approach for reducing the 1/f noise in MR sensors by using a MEMS resonator to mechanically modulate the magnetic field signal to a high frequency, where the 1/f noise vanishes. This mechanism improves the MR element sensitivity by 2-3 orders of magnitude in the low frequency sensing range. A fully integrated fabrication process was developed, where the MR sensor is fabricated first on the surface of a SOI wafer and the MEMS actuators are fabricated last...

BPN656: Airborne Particulate Monitoring Using a Micromechanical Electrometer

Gerardo Jaramillo

Environmental air quality is monitored by accurately sizing and quantifying nanometer-sized aerosol particles present in the atmosphere. One method of detection electrically charges the particles and then feeds a stream of charged particles into a Faraday cup electrometer. We present the first results of a MEMS based electrometer for the detection of small currents from ionized particles in a particle detection system.

Project end date: 08/12/13

BPN485: Ultrasonic Gesture Recognition on a Chip

Richard J. Przybyla
Hao-Yen Tang

Optical 3D imagers for gesture recognition, such as Microsoft Kinect, suffer from large size and high power consumption. Their performance depends on ambient illumination and they generally cannot operate in sunlight. These factors have prevented widespread adoption of gesture interfaces in energy- and volume-limited environments such as tablets and smartphones. Gesture recognition using sound is an attractive candidate to overcome these difficulties because of the potential for chip-scale solution size, low power consumption, and ambient light insensitivity. Our research focuses on...

BPN499: HEaTS: Aluminum Nitride Inertial Sensors for Harsh Environments

Fabian T. Goericke

Aluminum nitride (AlN) is a promising candidate for an emerging field of sensors that is inaccessible for electrostatic devices. Harsh environment conditions, such as temperatures above 500 deg C, high pressures, or reactive media are detrimental to today's MEMS sensors. Devices based on the inert, high melting point material AlN however can withstand these and even harsher conditions. The piezoelectric properties of the material are preserved to very high temperatures (up to 1000 deg C) and can be used for sensing in accelerometers and both sensing and actuating in gyroscopes....

BPN642: 10 MHz Optical Phased Array Metrology and Control

Mischa Megens

Very fast optical beam steering and wave front correction can be achieved by employing phased arrays of lightweight High Contrast Grating (HCG) MEMS mirror etalons. The etalons provide a large phase shift for a small displacement, 100x more than traditional reflective mirror elements. Operating such etalon arrays requires exquisite control of the MEMS mirror displacements. Our aim is to use in-situ stroboscopic interferometric imaging of the etalons to ensure phase accuracy and combat long term-drift, while employing feed-forward electrical input shaping to achieve fast settling time...

BPN663: HEaTS: SiC Diodes and Rectifiers for Harsh Environment Sensing Applications

Shiqian Shao

The goal of this project is to develop harsh environment rectification and sensing circuits. The devices and circuits are designed in silicon carbide (SiC) wafer due to its extraordinary performance in harsh environment such as high temperature, corrosive chemical. SiC diodes and rectifier bridges is designed, fabricated and tested in my research project to develop harsh environment sensing system.

Project end date: 01/28/14

BPN661: HEaTS: SiC Thin-Film Flame Ionization Sensor

David A. Rolfe

This project seeks to construct a thermally-isolated, SiC thin-film, ionization sensor to measure the propagation speed of flames in combustion chambers. Silicon carbide has been chosen as the sensor material because it is a ceramic semiconductor with low surface energy and excellent mechanical and electrical properties at high temperatures. A prototype MEMS planar sensor array has been designed and fabricated for parametric testing of sensor material and geometry. It is currently undergoing testing using a controlled flame. Future work will incorporate parametric optimization and...

BPN638: HEaTS: SiC Devices and ICs for Harsh Environment Sensing

Ayden Maralani

The main objective of this research is to design and develop low power Silicon Carbide (SiC) based transistors and Integrated Circuits (ICs) that can withstand the elevated temperature, up to 600°C. The fabricated ICs will be integrated with the SiC-based sensors to develop high temperature sensing systems for various harsh environment applications.

Project end date: 01/28/14

BPN644: HEaTS: SiC Bipolar Junction Transistors for Harsh Environment Sensing Applications

Nuo Zhang

The goal of this project is to develop silicon carbide (SiC) bipolar junction transistors (BJTs) for harsh environment sensing applications. The wide bandgap energy (3.2eV) and low intrinsic carrier concentration allow SiC semiconductor device to function at a much higher temperature than Si. Moreover, high breakdown field (3-5MV/cm), high-saturated electron velocity (2E7cm/s) coupled with high thermal conductivity (3-5W/cmK) permit extreme working conditions for SiC devices. The SiC BJT has the potential for low specific on-resistance, low turn-on voltage and high temperature...