Product Briefing Outline: Lotus Systems GmbH, a manufacturer of wet process, cleaning, and chemical management systems for photovoltaic, semiconductor, and MEMS production, has developed a Vertical Spray Cleaner for cleaning trays from nitride residues. The new vertical spray cleaners allow manufacturers to clean the carriers themselves – quickly, efficiently, and at their own facilities. Spraying ensures that there is always a reactive medium on the surface and makes cleaning two to three times faster.
Problem: Coating solar cells with silicon nitride results in a build up of nitride on the cell trays. In order to maintain the mechanical properties these residues must be removed periodically. Usually, manufacturers have an external service clean the trays in immersion baths and then return them. This takes up an unnecessary amount of time and money. Additional trays are necessary to continue production. A significant quantity of trays breaks when they are handled. On top of everything, the central problem is that immersion baths use up large volumes of chemicals.
Solution: Lotus Systems has developed vertical spray cleaners that allow manufacturers to clean the trays themselves – quickly, efficiently, and at their own facilities. Spraying ensures that there is always a reactive medium on the surface and makes cleaning two to three times faster compared to immersion cleaning. Only about a tenth of the chemicals is needed. Uniform cleaning of all surface areas is achieved by sophisticated arrangement of the nozzles and linear motion of the spray bars. With this technology LOTUS brings the costs down to about €20 per carrier. This means about 75% savings compared to costs for external cleaning. Plus, the carriers are ready for use again after 12 hours. The vertical spray cleaners, with their extremely small footprint of 1.8 square meters, can easily be integrated into a cell fab.
Applications: Tray Cleaning, Removal of SiN by HF / HNO3
Platform: The tool can handle 6 trays up to 1.840 x 1.000 mm or 3 trays up to 2.000 x 1.500 mm with an uptime of > 98 %. Optionally it can be offered in FM4910-compliant material and the waste-water tank can be equipped with a drain pump instead of gravity drain.
Availability: Currently available.