Germany – Laboratory, optical and precision equipments (excl. glasses) – OV_LK_08-26-0886 Cz-Züchtungsanlage-Fluoride-2027

Delivery "free site", installation and commissioning of a Cz growth system for growing fluoride single crystals. Additionally: provision of documentation, acceptance (factory and final acceptance), service in case of malfunction. The system enables the growth of fluoride single crystals from the melt using a pulling method (e.g. Czochralski method). The system is used in a research environment and must ensure frequent user access, easy maintenance, and high process stability. The system should be able to produce crystals with a maximum diameter of 100 mm (4 inches) and a weight of up to 5 kg. The maximum inner diameter of the crucible is estimated to be approximately 200 mm. The crystal growth process takes place in a water-cooled stainless steel chamber, the inner wall of which must be electropolished to achieve a high vacuum. Argon and CF4 are used as process gases. The system must have a bake-out function, i.e. the chamber must be able to be evacuated to a high vacuum (<1×10-6 mbar) under heating to >50 °C. The process is carried out at a pressure slightly above atmospheric pressure (typically 1.05-1.1 bar) in a static or flowing atmosphere. The starting material is located in a carbon-based crucible (graphite or glassy carbon), which is heated in the center of the stainless steel chamber. Heating is carried out by means of a graphite resistance heater, which heats the crucible and the melt. The crystallization process is initiated by a seed crystal, which is attached to a rotating and translationally movable shaft made of platinum and immersed in the melt. The seed crystal is then slowly pulled out of the melt under rotation, resulting in a volume single crystal.