| 摘要 |
PURPOSE:To secure a mask in high reliability by providing an electromagnet to a member for mounting the mask, and attracting the mask of a magnetic substrate. CONSTITUTION:A mask chuck 1' is composed of a magnetic material, a coated wire 15 is wound on the outer periphery to form a coil 15. When the coil 15 is energized, the chuck 1' becomes a cylindrical magnet. When a mask substrate 6' is composed of a ferromagnetic material, the chuck l' attracts fixedly by the magnetic force the mask 6'. The attracting force can be arbitrarily controlled by the number of turns of the coil 15 and the current value, and when the current is interrupted, the attraction can be released. With this structure, no vacuum is used, a loss of He leakage or a vibration of the mask 6' due to the variation in the attracting force and the leakage amount can be eliminated. Ultrafine dust particles in the He are not attracted to the attracting surface of the mask due to He leakage current, and the X-ray exposure mask can be reliably secured. |
