Integrated Multifunctional Environmental Sensors

We present the design, microfabrication, and characterization of ten sensors on one silicon die. We demonstrate simultaneous monitoring of multiple environmental parameters, including temperature, humidity, light intensity, pressure, wind speed, wind direction, magnetic field, and acceleration in th...

Full description

Saved in:

Bibliographic Details
Published in:	Journal of microelectromechanical systems Vol. 22; no. 3; pp. 779 - 793
Main Authors:	Roozeboom, C. L., Hopcroft, M. A., Smith, W. S., Joo Yong Sim, Wickeraad, D. A., Hartwell, P. G., Pruitt, B. L.
Format:	Journal Article
Language:	English
Published:	New York, NY IEEE 01-06-2013 Institute of Electrical and Electronics Engineers
Subjects:	Applied sciences Capacitive sensors Electrostatic devices Exact sciences and technology Fabrication Humidity Mechanical engineering. Machine design micromachining piezoresistive devices Precision engineering, watch making sensor fusion sensor systems Silicon Temperature measurement Temperature sensors micromachining Photofabrication Precision engineering fabrication Measurement sensor sensor fusion Electrostatic devices piezoresistive devices Engineering design sensor systems Humidity Integrated design Monitoring Wafer Production process
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	We present the design, microfabrication, and characterization of ten sensors on one silicon die. We demonstrate simultaneous monitoring of multiple environmental parameters, including temperature, humidity, light intensity, pressure, wind speed, wind direction, magnetic field, and acceleration in three axes. Through an integrated design and fabrication process, these ten functions require only six photolithography mask steps. Temperature is measured redundantly using aluminum and doped silicon resistance thermal detectors and a bandgap temperature sensor. Humidity is transduced by the dielectric change of a polymer due to water absorption. Light intensity is measured with a p-n junction photodiode and doped silicon photoresistor. Pressure is transduced using piezoresistor strain gauges on a sealed membrane. Wind speed and direction are measured with two perpendicular hot wire anemometers. Magnetic field strength is measured with a doped Hall effect sensor. Acceleration in three axes is measured using electrostatic comb finger accelerometers, and an additional z -axis accelerometer uses piezoresistor strain gauges. We measured the cross-sensitivity of each function to all other environmental parameters and can use the chip's multifunctional capabilities to compensate for these effects. Sensor integration can enable significant cost, size, and power savings over ten individual devices and facilitate deployment in novel applications.
ISSN:	1057-7157 1941-0158
DOI:	10.1109/JMEMS.2013.2245400