Thermal Phenomena in Free Standing Thin Films and Biological Microsystems

Download or read book Thermal Phenomena in Free Standing Thin Films and Biological Microsystems written by Ankur Jain and published by . This book was released on 2007 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thermal performance of Microelectromechanical Systems (MEMS) as well as Integrated Circuits (ICs) depends critically on the thermophysical properties of constituent thin film materials. This work develops a method for thermophysical characterization of free-standing thin films based on the thermal response of the thin film to a sinusoidal heating current. MEMS-based microheater structures with silicon nitride and NiTi membranes are fabricated and thermally characterized using the method. Measured values of thermal conductivity and heat capacity for silicon nitride are found to agree well with previous measurements. Thermal conductivity measurements for thin film NiTi indicate a 40% reduction in thermal conductivity compared to the well known bulk value. Heat capacity of thin film NiTi increases with temperature in the low temperature phase, and saturates in the high-temperature phase. Theoretical modeling and measurements presented in this work are expected to aid in improved thermal modeling of microsystems comprising of thin film membranes, particularly those employing the shape memory effect.