VON ARDENNE offers vacuum process expertise and the respective key components for almost the entire spectrum of thin-film photovoltaics. Electron beam and plasma technologies are appropriate to deposit functional and contact layers on large areas with different process temperatures. Vacuum process technology can deposit extremely thin layers on different substrate materials, such as glass, silicon wafers, metal strip or polymer films.
Magnetron sputter sources generate a magnetic field-enhanced plasma discharge under low pressure and in Ar‑atmosphere. By bombarding coating material (target) operated as cathode with positive Ar‑ions, single atoms are knocked out of the target surface. These atoms condense on the substrate to be coated as a continuous thin film. Adding reactive gases, such as N2 or O2, may further generate plasma-chemical reactions. Thin nitrides or oxides can be generated as thin layers in this way.
Magnetron sputter sources enable the highly precise deposition of complex compound layers on large areas. Therefore, these sources form the technological basis for manufacturing many of the layer systems of photovoltaics.
The cylindrical target is rotating during the sputtering process thus being ablated almost uniformly at its surface. High target utilization (up to 85%) and an improved operating lifetime lead to significantly lower coating costs compared to planar magnetron sputter sources.
Through selection of appropriate source types and targets as well as through insertion of reactive gases, most photovoltaic layers can be manufactured at high rates and uniformity including:
Electron beam guns are applied for high-rate evaporation of metals and dielectric compound materials. High-power electron beams are directed toward the source material with a programmable energy distribution. In this way, the guns generate high temperatures and evaporation rates. The thermally evaporated material deposits on the surface and continuously forms layers of high quality.
A wide range of different configurations permits the evaporation of materials and compounds significant for photovoltaic applications, e.g.:
