Effective Young’s Modulus of Complex Three Dimensional Multilayered Ti/Au Micro-Cantilevers Fabricated by Electrodeposition and the Temperature Dependency

Hitomi Watanabe,Shinichi Iida,Masato Sone,Katsuyuki Machida,Michael Schneider,Tso-Fu Mark Chang,Kazuya Masu,Chun-Yi Chen,Daisuke Yamane,Hiroyuki Ito,Ulrich Schmid

doi:10.3390/electrochem2020015

Hitomi Watanabe, Shinichi Iida + Show 9 more

Open Access

https://doi.org/10.3390/electrochem2020015

Copy DOI

Abstract

Ti/Au multi-layered micro-cantilevers with complex three-dimensional structures used as micro-components in micro-electromechanical systems (MEMS) sensors were prepared by lithography and electrodeposition, and the effective Young’s modulus was evaluated by the resonance frequency method and finite element method simulation. Effects of the constraint condition at the fixed-end of the micro-cantilever and the temperature dependency of the effective Young’s modulus were studied. Three types of the constraint at the fixed-end were prepared, which were normal type (constraining only bottom surface of the fixed-end), block type (constraining both top and bottom surfaces), and bridge type (top surfaces covering with a bridge-like structure). The temperature dependency test was conducted in a temperature range from 150 to 300 °C in a vacuum chamber. An increase in the effective Young’s modulus was observed as the constraint condition became more rigid, and the effective Young’s modulus merely changed as the temperature varied from room temperature to 300 °C.

Highlights

Size reduction and performance enhancement of micro-electromechanical systems (MEMS) devices are always challenging and important research interests, especially for MEMS devices, such as MEMS accelerometers commonly equipped in smartphones
Size reduction of MEMS devices having the sensitivity greatly affected by the noise level, such as Brownian noise, is difficult since the noise level is dependent on the overall mass of the key components, and a number of mass or volume is needed to maintain a low noise level or high sensitivity
Devices has received a great amount of attention, and MEMS accelerometers employing gold components prepared by electrodeposition are reported to have a small size whiling retaining high sensitivity [2,3], which is mainly contributed by gold’s high mass density

Summary

Introduction

Size reduction and performance enhancement of micro-electromechanical systems (MEMS) devices are always challenging and important research interests, especially for MEMS devices, such as MEMS accelerometers commonly equipped in smartphones. Detection of body tremors [3] and muscular sounds [4] has been reported using a highly sensitivity MEMS accelerometer. Size reduction of MEMS devices having the sensitivity greatly affected by the noise level, such as Brownian noise, is difficult since the noise level is dependent on the overall mass of the key components, and a number of mass or volume is needed to maintain a low noise level or high sensitivity. The application of gold-based materials to MEMS devices has received a great amount of attention, and MEMS accelerometers employing gold components prepared by electrodeposition are reported to have a small size whiling retaining high sensitivity [2,3], which is mainly contributed by gold’s high mass density (19.3 × 103 kg/m3 at 298 K [6]).

Methods

Discussion

Conclusion