Fabrication process of high aspect ratio elastic and SU-8 structures for piezoelectric motor applications

We report on recent advances in micro fabrication technology using micromolding and high aspect ratio structuring of photopolymer. The direct application is the realization of components for millimeter-size, ultrasonic piezoelectric motors. A new fabrication process using a thick epoxy-based material (SU-8) and the electroplating of nickel is demonstrated. Photopolymer structures have also been realized and released using a positive tone resist as sacrificial layer. The main advantages over past fabrication methods are better design flexibility, simplicity of the fabrication process, the capability to combine metallic materials (Ni) with polymeric materials ( SU-8), and the use of positive tone resist as a sacrificial layer. (C) 1998 Elsevier Science S.A. All rights reserved.

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