Improved DLC coatings by more efficient process design

Diamond-like carbon (DLC) coatings are well known for their exceptional properties such as low friction coefficient combined with high hardness and wear resistance, chemical inertness, optical transparency and adjustable electrical conductivity. They are well-established in a large variety of technical applications and industrial branches. Examples are automotive industry, machine elements, cutting and forming tools.
Common technologies for fabricating DLC coatings are either based on a PECVD (plasma enhanced chemical vapor deposition) process with mid-frequency discharges or on a PVD setup with a Carbon sputtering target in combination with assisting reactive gas such as C2H2. The latter can be considered as a PVD/PECVD hybrid process. Additionally, PVD processes are applied to deposit interlayers for guaranteeing good adhesion between the DLC coating and the substrate.
Complex substrate geometries and variable arrangements as occurring in everydays DLC coating business are challenging in terms of film homogeneity, reproducibility of the same coating on numerous substrate parts and overall process stability. Therefore, every new substrate configuration requires experiments for adjusting optimal deposition conditions, which significantly limits the time and cost-efficiency of the coating production.
In order to enable improved productivity and quality of DLC coating processes, DLCplus aims for systematic investigation and classification of relevant mechanisms in DLC coating processes which are determining the reproducibility and quality of the DLC coated products. To achieve this goal, the transport and plasma dynamics in the deposition process as well as the atomistic film growth dynamics as a function of impinging flux and energy will be analyzed by experiments and within simulation models. The latter include process models of transport and plasma dynamics in carbon based PVD and C2H2 based PECVD processes. Further, atomistic models describing the growth and morphology of carbon-based layers are applied.
The envisaged cooperation between Materia Nova, University of Namur and Fraunhofer IST is necessary since it allows for combining the required experimental platforms and simulation technologies in a complementary and synergistic way. The user committee mainly consists of companies from metalworking and automotive industries, coater manufacturers and job coaters. They will contribute industrial-relevant substrate geometries, process conditions and product specifications, which focusses the project work on the demands of the market. In summary, we will obtain a full picture for the multi-scale problem of DLC coating with respect to better understanding the most relevant mechanism determining the product quality and reproducibility.
Aiming for improved quality and efficiency of DLC coating processes, results from DLCplus will enable novel coater concepts and recipes, effectively improving film homogeneity as well as film quality and process stability.