Professor Hans-Werner Schmidt

Polyimides are high performance polymers and exhibit high thermal stability, excellent chemical resistance, and good mechanical properties. Polyimide thin films play an important role in optical, electronic, and electro-optic devices such as LC-Displays. In addition to the common fabrication of such thin films from solution, vapor deposition of polyimide forming monomers is an alternative promising approach. The solvent free vapor deposition polymerization can be applied to insoluble and non-meltable monomers resulting in polyimides with superior stability and further enhanced material properties.

2. What has motivated you to conduct this work? 

The development of combinatorial techniques in material science facilitates the experimental setup and reduces the number of experiments for generating structure-property relationships. This combinatorial approach is designed to investigate the orientation behavior of monomers and their resulting polyimide thin films. The combinatorial approach addresses elegantly the immense number of parameters such as nature and composition of monomers, evaporation rate, layer thickness, nature of aligning surface, sequential or co-deposition, and imidization conditions. These parameters can be systematically varied and investigated in this way.

3. Where do you see this work developing in the future? 

Combinatorial experiments involving vapor deposition have been realized in our group and by others, and the simplification of optimization experiments for opto-electronic devices in particular is intriguing and far from being completely explored and finished.

4. Are there any particular challenges facing future research in this area? 

Vapor deposition of organic molecules is a reliable and commercially applied technique for the fabrication of devices and thin films. However, not every material or chemical compound is able to be vapor deposited, e.g. polymers or inorganic salts. Thus the development of suitable molecules and monomers, the adaptation and modification of new methods and materials are among the challenges encountered to further improve and develop complex multilayer thin film structures with enhanced properties and performance.