| 摘要 |
PURPOSE:To improve durability of a furnace core tube by providing a cap integrally with an operating jig which brings a diffusion boat in and out and making the diffusion boat sit by vertical and parallel movement. CONSTITUTION:An operating jig 11 proceeds into a furnace core tube 2 without contact with the inner surface of the tube 2 housing a diffusion boat 9 wherein a wafer is placed in a housing portion 12 of the boat 9. When the diffusion boat 9 arrives at a definite position A, a cap 13 comes in contact with the opening 4 of a furnace and closes the opening 4. Then, a sitting means 15 make the operating jig 11 sit on the inner surface of the tube 2 in a state of holding the operating jig 11 horizontally and a diffusion process is carried out. The inner surface of the furnace core tube 2 is not damaged by the movement of the diffusion boat 9. The weight of the diffusion boat 9 is supported by the sitting means 15 and deformation by fatigue of the furnace core tube can also be prevented. |
