What if there is a watermark after cleaning the silicon wafer?

1. If the washing is not clean, you can take some clean silicon wafers and clean them again. Do not go through the cleaning agent tank to see if there is any watermark. If there is no watermark, it is a problem with the cleaning agent, just adjust it.
2. The drying is not enough. Take out the silicon wafer before entering the drying channel to dry or blow dry to see if there is a watermark. If there is no watermark, increase the intensity of the drying channel.
3. The content of impurities in the water is too high, making it difficult to clean, just remove the impurities in the water.