METHOD OF REPLACING THE GAS IN THE CHAMBER

摘要

PURPOSE:Porous walls are placed along the walls and the air is sent into the space between the chamber walls and the porous walls so that the pressure is made a little higher than that in the chamber to effect high-efficiency displacement of the old gas in the chamber with the new gas sent into the space. CONSTITUTION:Porous walls 2 are lined along the wall surfaces of the chamber with a certain space and a gas such as nitrogen is sent through inlets 4A and 4B in the space 3. The gas flows quietely and uniformly through the porous walls into the chamber so that the gas layer 7 is formed along the inside surface of the porous walls and it gradually grows. At the same time, the old gas in the chamber is excluded from the duct 5 by an amount equal to that of the new gas supplied.