Design, Implementation, and Testing of a Hybrid Thermal Microactuator

Abstract

The article offers an analytical model, finite-element analysis, and testing results of a microelectromechanical system (MEMS)-based hybrid thermal microactuator. A hybrid design of a thermal microactuator is designed and fabricated according to the standard microfabrication technology, silicon-on-insulator multiuser MEMS processes (SOIMUMPs) of MEMSCAP. Iterative coupled electromechanical and electrothermal finite-element analyses (FEAs) are performed showing a total displacement of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$12.044 \mu \text{m}$ </tex-math></inline-formula> at an input power of 252.6 mW, which is quite comparable to the experimental result of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$12.041 \mu \text{m}$ </tex-math></inline-formula> displacement at 264.7 mW. It is noted that a maximum temperature reading of 535 °C is achieved during electrothermal FEA which is in close correlation to the 495 °C of experimental thermal testing of the fabricated hybrid thermal microactuator. The analytical and simulated model is used to study the detailed profile behavior of dimensional displacements and temperature gradients of the designed hybrid thermal microactuator. Micromanipulation experiments successfully demonstrate the desired displacement at relatively low input power. The total size of the microactuator is reported to be <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.5\times0.47$ </tex-math></inline-formula> mm2.