Abstract
This paper investigates how silicon nitride thickness impacts the performance of silicon nitride-aluminum bimaterial cantilever infrared sensors. A model predicts cantilever behavior by considering heat transfer within and from the cantilever, cantilever optical properties, cantilever bending mechanics, and thermomechanical noise. Silicon nitride-aluminum bimaterial cantilevers of different thicknesses were designed and fabricated. Cantilever sensitivity and noise were measured when exposed to infrared laser radiation. For cantilever thickness up to 1200 nm, thicker silicon nitride results in improved signal to noise ratio due to increased absorptivity and decreased noise. The best cantilever had an incident flux sensitivity of 2.1 × 10 -3 V W -1 m 2 and an incident flux signal to noise ratio of 406 Hz 1/2 W -1 m 2, which is more than an order of magnitude improvement compared to the best commercial cantilever.
Original language | English (US) |
---|---|
Pages (from-to) | 17-23 |
Number of pages | 7 |
Journal | Sensors and Actuators, A: Physical |
Volume | 185 |
DOIs | |
State | Published - Oct 2012 |
Externally published | Yes |
Keywords
- Bimaterial cantilever
- Infrared sensor
- Thermomechanical
- Thermometer
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Instrumentation
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering