Micropositioning systems are widely used in many applications, for example, optical industry, medical devices, and micro-assembly applications. Commonly, MEMS-based micropositioning systems use conventional fabrication techniques such as lithography, etching, and thin-film processes. However, a typical microfabrication process by using the masking and etching operations is limited to fabricate a 3-dimensional complex device. This research presents a novel design of a 3D micropositioning system with electrostatic comb drives with a converting mechanism. The device can convert the in-plane motion to the out-of-plane displacement. The proposed model is possible by using FEMTOPRINT®, machine which combines material modification by femtosecond laser-beam and chemical wet etching. The results from the simulation shown that the 3Dcomplex micropositioning system can achieve a wide range of workspace up to 1$,212.79 \mu \mathrm{m}^{2}$. In X-axis and Z-axis, it can translate up to a maximum displacement of $33.34 \mu \mathrm{m}$ and $75.14 \mu \mathrm{m}$ respectively, while the footprint of the device is $1.65 \times 1.10$ mm2. This device can be a new prototype of MEMS based-micropositioning system named “glassy MEMS” that is suitable for a 3D-complex mechanism and can be used in many applications.

Design and Simulation of XZ MEMS Micropositioning with 3D-Complex Structure

This paper presents design, simulation results and envisaged fabrication process for a versatile MEMS bimorph actuator with large out of plane displacement and high resolution. A comparative study of mechanical, thermal and electrical response of the micro-actuator is presented by using two well-known MEMS simulation tools. The bimorph structure measuring 700 × 1280 mm2 is fully integrable with CMOS fabrication process. It is indented for tunable filter applications where the precise vertical motion of the payload, the top metallic electrode anchored rigidly to bimorph ‘springs’ spans the vertical range of 250-300 microns with submicron resolution. Each bimorph spring resembles a hair pin structure and is composed of materials with large difference in thermal expansion coefficients e.g. electroplated gold and polysilicon for optimal out-of-the plane deflection. The novel structure can also be configured for analog micro-mirror based optical and IR spectroscopy applications by controlling the actuation bias and top electrode surface parameters.

Aarushee Rangra

Papers

A versatile MEMS bimorph actuator with large vertical displacement and high resolution: Design and fabrication process