| 摘要 |
PURPOSE:To enable to significantly reduce the number of microscopic dusts by a method wherein a vacuum drawing and a venting are repeated to a treating container. CONSTITUTION:In a vacuum-system control unit 11, a valve 3a between a treating container 1 and a vacuum pump 4 and a valve 3e between the vacuum pump 4 and a vacuum gauge 7a are controlled by the signal of a CPU14. In a venting- system control unit 12, a valve 3c between the container 1 and an N2 gas source 6 and a valve 3f between the container 1 and a vacuum gauge 7b are controlled by the signal of the CPU14. In the title device constituted in such a way, a vacuum drawing and a venting are repeated to the treating container 1 on the basis of the previously set schedule and the previously detected pressure. As a result, the number of microscopic dusts as small as 0.2- several microns, which stick to a wafer, can be reduced to one-several tenths, compared with the conventional method having been hiterto prevailed. |
