Micro hot embossing and micro laser welding technologies for fluidic applications

This paper will show the realization of micro structures in polymeric materials including the preparation of high precision embossing masters. For embossing a two-depth silicon master tool was developed, that is known as 2.5 dimensional pattern. Goal of the investigation and reason for the second depth was the implementation of a special welding structure and the realization of smallest possible join formation between polymer substrates. After the Si master tool was realized the micro structures were molded to a so called soft working stamp. Using this stamp the patterns were transferred to a polymeric substrate under accompanying characterization and measurement. At least the channel like structures should be covered by another polymer. Therefore a laser transmission welding process was developed. With an additional absorbing layer two transparent substrates were welded by an infrared laser. Finally the strength of the bonding interface was character-ized by a micro chevron pull test