| 摘要 |
PURPOSE:To make it possible to prevent contamination of a substrate and adhesion of any undesirable deposit to the substrate, by providing a semiconductor subsrate mount having guide parts formed at two ends of the upper flat surface thereof, and further providing a shielding plate which is slidable along the guide parts. CONSTITUTION:A mount 13 is disposed inside a reaction tube 1, and guide parts 14 are formed on the mount 13. A quartz shielding plate 17 is superimposed over the mount 13 so that the guide parts 14 are respectively fitted into two grooves formed in the shielding plate 17. In an early stage of the formation of a thin film, the shielding plate 17 is slid leftwardly (as shown in the figure) along the guide parts 14 so that the plate 17 is interposed between a substrate 3 and the respective ends of various gas supply pipes 5-7, whereby the shielding plate 17 prevents the substrate 3 from being contacted by various gases from the supply pipes 5-7 or other unnecessary gases and further prevents any deposit from adherig to the substrate 3. When the flow rate of each of the gases reaches a stationary value, the shielding plte 17 is slid rightwardly, thereby exposing the substrate 3. With this structure, the operation of the plate 17 is extraordinarily simplified, and it is possible to prevent contamination of the substrate 3 and adhesion of any deposit to the substrate 3. |
