Comparison between conduction and convection effects on self-heating in doped microcantilevers

Sensors (Basel). 2012;12(2):1758-70. doi: 10.3390/s120201758. Epub 2012 Feb 9.

Abstract

The present study investigates the effects of thermal conduction and convection on self-heating temperatures and bimetallic deflections produced in doped microcantilever sensors. These cantilevers are commonly used as sensors and actuators in microsystems. The cantilever is a monolith, multi-layer structure with a thin U-shaped element inside. The cantilever substrate is made of silicon and silicon dioxide, respectively, and the element is p-doped silicon. A numerical analysis package (ANSYS) is used to study the effect of cantilever substrate material, element width, applied voltage and the operating environments on cantilever characteristics. The numerical results for temperature are compared against their analytical models. Results indicate the numerical results are accurate within 6% of analytical, and Si/Si cantilevers are more suitable for biosensors and AFM, whereas, Si/SiO(2) are for hotplates and actuators applications.

Keywords: bimetallic effect; biosensors; electrical resistivity; hotplates; microcantilever; piezoresistivity; self-heating.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Equipment Design
  • Equipment Failure Analysis
  • Heating / instrumentation*
  • Micro-Electrical-Mechanical Systems / instrumentation*
  • Thermal Conductivity
  • Thermography / instrumentation*
  • Transducers*