| 摘要 |
PURPOSE:To avoid a pollution on the charge or discharge of a semiconductor substrate to or from a core pipe by surrounding the core pipe constituting a diffusion furnace by a scavenger, blowing a non-oxidizing gas against the core pipe from a plurality of nozzles set up in the scavenger and previously generating a curtain of the gas to the core pipe. CONSTITUTION:The projecting end section of the core pipe 3 constituting the diffusion furnace 1 is surrounded by the concentrical scavenger 4, and a plurality of the nozzles 10, noses thereof are directed in the axial direction of the core pipe 3, are disposed in the scavenger. Opening sections at the noses of the nozzles 10 are positioned at a charge or discharge port for the base plate 5 of the semiconductor substrates 2 encased in the core pipe 3, the non-oxidizing gas, such as nitrogen gas, a forming gas, etc. is blown off from the port, and the gas curtain is generated in the port. Accordingly, the outside air does not intrude in the core pipe 3 when the base plate 5 is charged or discharged, and the pollution of the substrates is reduced remarkably. |
