Cleaning of disc substrate

摘要

The method involves initially detaching the dirt by a spray of cleaning fluid, at a pressure of 20-150 bar, while the substrate is rotated on a turntable with retracted brushes. The brushes remove the dirt by being positioned at a narrow gap from the substrate surface, without contact, and with a further feed of the cleaning fluid. The cleaning fluid is water, with preferably an ionised water for the first stage. During the first stage a jet delivers the cleaning fluid at right angles to the disc, and has a radial movement. The water stream at the disc surfaces forms an overlapping spiral. For both stages, the turntable is rotated at about 100 rpm, and a spin drying action is effected with the turntable speed at 2000-3000 rpm, to spin off any cleaning fluid from the disc surface, together with a flow of nitrogen directed over the disc surface. The brush is rotated at a higher speed than the substrate below, and in the same rotation direction.