Impact of silicon nitride thickness on the infrared sensitivity of silicon nitride-aluminum microcantilevers

This thesis 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.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2012

Author dc:creator

• Rosenberger, Matthew

Contributors dc:contributor

• King, William P.

• bimaterial cantilever
• thermomechanical
• thermometer
• infrared sensor

Statement dc:rights

• Copyright 2012 Matthew Rosenberger

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/31048

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/31048