The method of sputter deposition is a widespread technique for the production of extremely thin films on the order of some nm to microns.The field of applications are manifold and range from photovoltaics and functional films for architecture (e.g. heat insulation, sunscreen, self-cleaning surfaces, hard coatings) to transparent electrodes for example for TFT displays. Also the phase change materials investigated in our institute are deposited using the sputter technique.

Despite its extensive application, the physical processes involved remain partly unclear as of today. Though many models for the theoretical description were developed and refined, there still remain some unresolved problems, rendering sputter deposition an active field of research. Especially for the design of equipment for large-scale film production it is important to understand how to control all parameters influencing the process and the film properties in order to achieve optimal quality. For that reason it is the main goal of our group to improve existing physical models describing sputter deposition or to develop new ones where necessary based on a detailed understanding.

To achieve this, we operate two different sputter chambers and investigate in detail the correlations between process parameters and resulting films. For the film analysis, we employ the manifold experimental methods that are available in our institute, while for the sputter deposition itself, we employ custom methods for process analysis and control. In addition to the widespread DC Magnetron Sputtering (DCMS) we also operate a pulse generator that is able to generate very short high-current pulses needed for High Power Pulsed Magnetron Sputtering (HPMS). The high current densities significantly change the kinetics of HPMS compared to DCMS and hence yield an effective tool to modify the properties of thin films. Especially for the investigation of the novel high power sputtering, we employ a custom spectrometer that enables us to analyse the optical emmision spectra of the plasma with high energetic and temporal resolution. On the one hand, the results allow for a better understanding of the sputter process, supplementing the development of new theoretical models. On the other hand, correlations of the process parameters to the film properties can be studied this way. By means of an ion gun incorporated into the sputter chamber, the effect of ion bombardment on the film growth can be observed. This is useful as ion bombardment is a common effect observed in sputter chambers, so the controlled variation of the ion bombardment enables us to derive conclusions on how the films are affected by that.

Our research addresses both theoretical and technical aspects of sputter deposition as well as the investigation and optimization of resulting films. Often these films are of particular industrial interest. Because of our contacts to other research facilities and industrial partnerships, our group is engaged not only in the development of the field but also the development of new products. For an overview of our scientific results, please take a look at our list of publications. In our list of open positions you can get information on how you could participate in our work.