Design and fabrication of PDMS‐based electrostatically actuated MEMS cantilever beam

Abstract

Polymer microelectromechanical system (MEMS) devices emerge as the new class of sensor devices for bio-sensing applications exhibiting high mechanical deformability and sensitivity. In this work, the design and fabrication of electrostatically actuated polydimethylsiloxane (PDMS) MEMS cantilever on flexible PDMS substrate is presented. The physical parameters of the cantilever were analysed and optimised using Taguchi method coupled with COMSOL Multiphysics software. This work focusses on the development of a novel approach for the simple and cost-effective fabrication process of PDMS cantilevers and subsequently its arrays. The proposed device consists of a PDMS body with the metal bottom electrode, PDMS anchor, and PDMS cantilever beam as its top electrode and immobilization surface. The work presented is of the cracking phenomenon in the metal layer sputtered on the PDMS substrate. The novelty of the fabrication process is the use of low-cost processes, no need for sophisticated lithography tools or etching equipment. Also, the process allows the use of alternate material as base substrate (glass, silicon wafer etc.) wherein it is not consumed and is reusable. The fabricated device is then electrically characterised for its pull-in characteristics.

A Review of Actuation and Sensing Mechanisms in MEMS-Based Sensor Devices

“…When the device is moved by y toward the fixed comb finger one as appeared by (Fig. 13b), the capacitances C 1 and C 2 will be changed and relying upon that shift, and their values can be calculated using (11) and (12), respectively.…”

“…In recent developments, microscale batch fabrication of pressure, temperature, inertial etc., sensors have been demonstrated for batch scale using similar chip handling unit. The accurately superimposed a system on a chip can enable the operation of complex systems [ 10 , 11 ].…”

Stiffening of polydimethylsiloxane surface as result of exposure to low‐pressure argon discharge plasma

“…Polydimethylsiloxane (PDMS) has received great attention in the recent years due to its good mechanical properties, optic transparency, moldability, dielectric strength, chemically inertness, gas permeability, and biocompatibility, [ 1 ] properties that make this material a good candidate for applications in fabrication of biomedical devices, [ 2 ] microfluidic devices, [ 3 ] microelectromechanical system (MEMS) devices, [ 4 ] stamps used in micro‐contact printing soft lithography, [ 5 ] lab‐on‐a‐chip analysis systems, and many other devices.…”

Simulation and Design Optimization of Polymeric Micro-Structures based Bio-Sensors

“…These suspended microstructures can be operated in static or dynamic modes of operation [13]. In static mode, change in stress due to the added mass is measured as a result of the deflection of the cantilever [14,15], whereas in dynamic mode, a shift in the resonant frequency is observed due to the added mass [10,16]. Various other mechanisms are available and have to be selected depending on the nature of loading, the operating medium and the level of sensitivity required.…”