| 摘要 |
PURPOSE:To make the thickness of a photoresist film on a large sized wafer uniform by dropping photoresist liquid on a semiconductor substrate, subjecting the substrate to a compound revolutional movement such as planetary movement to average the velocity distribution on the whole surface of the substrate, coating thus the photoresist liquid. CONSTITUTION:A gear 2 is revolved by the revolution of a gear 1. Further, a gear 3 is installed above the gear 2 at a position apart from a central shaft 2' of the gear 2. The gear 3 is meshed with a gear 4 centering a central shaft 2'. The gear 3 is revolved around the gear 4 and rotated by the central shaft 3' by this constitution. Further, a wafer chuck 5 and a semiconductor wafer 6 are fixed to above the central shaft 3' of the gear 3 to subject the semiconductor wafer 6 to planetary movement. Photoresist liquid is dropped on the semiconductor wafer 6, and coated by averaging the velocity distribution of the whole surface of the wafer 6 by the compound revolutional movement, forming thus photoresist film. Since the resist liquid is coated with an averaged thickness, the thickness of the film, even if it is a large sized wafer, can be made uniform. |
