Dry release of SU-8 structures using OHP transparency as the substrate material

This paper describes a dry release method to release SU-8 structures developed using OHP transparency film as a substrate. This release of microfabricated SU-8 devices from the substrate involves no additional layer development. Standard photolithography processes have been used in this method, thus no expensive equipment and materials are used. Several SU-8 structures, from as large as an 8-cm diameter membrane to as small as a 25-μm cantilever, have been successfully released from its substrate in a fast and efficient manner. The quality of the SU-8 structures was assessed by SEM and AFM. The SEM and AFM images show that the released structures are free from damage and microcracks. In order to show the effectiveness of this release method, a micromixer consisting of microchannels were then fabricated using this method.