| 摘要 |
PURPOSE:To prevent contraflow of external atmosphere into a furnace when a material to be treated is inserted and adhesion of impurity on a semiconductor wafer by forming an air curtain at the entrance of the furnace wherein such heat treatment as thermal oxidation or diffusion of impurity is carried out. CONSTITUTION:At the end of a quartz tube 1 on the side where a material to be treated is inserted or extracted, an air blower 10 is provided. The air blower 10 is flat hood shape. On side walls 11 and 12 which are horizontally wide and installed face to face, a circular hole is formed respectively. The edge of the quartz tube 1 is inserted in the circular hole of the side wall 11 and the circular hole on the side wall 12 is covered with a lid 21. Looking at through these circular holes, one end of the hood is made an air outlet 13 and the other end is made an air inlet 14. A filter 22 is also installed on the air outlet 13. This construction provides an air curtain at the end of the quartz tube 1. |
