Laminated Photoresist Sacrificial Layer Process for 3-D Movable Suspension Microstructures in LIGA-Based Surface Micromachining

Abstract:

The fabrication process of three-dimensional (3D) high-aspect-ratio MEMS devices entirely made of electroplated metals with suspending multilayered microstructures is reported. The technology used is a LIGA-liked micromachining process, called the laminated positive photoresist sacrificial layer process (LPSLP). The LPSLP allows in UV-lithography not only for thick resist mould for electroplating of cascaded metal structures but also for the sacrificial layer for supporting mechanically the suspensions. So far the LPSLP procedure has incorporated with more than five sacrificial layers, which allows for the creation of overhanging structures and freely moving parts like out-of-plane cantilever stacks. A description of the underlying fabrication principle and processing details is discussed in this paper. Thus the proposed procedures open a low-cost route for fabricating micro-components such as cantilevers, bridges, movable electrodes, and freestanding parts.

• Periodical: Advanced Materials Research (Volumes 97-101)
• Pages: 2538-2541
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.97-101.2538
• Online since: March 2010
• Authors: Yi Bo Wu, Gui Fu Ding, Cong Chun Zhang, Hong Wang
• Keywords: 3-D Metal Microstructure, Laminated Sacrificial Layer, Movable Suspension, Positive Photoresist, Surface Micromachining

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