| 摘要 |
PURPOSE:To improve the uniformity of the distribution of temperature inside an oven, by providing at the open end of a heating vessel a hermetic sealing lid member and another lid member having a recess for inserting a jig for moving a wafer support. CONSTITUTION:A lid member 12 is provided with a recess 12a for inserting an operating rod into a heating vessel 1. First, with an open end 1a of the vessel 1 opened, a wafer support is inserted into the vessel 1. Then, the lid member 12 is rotated, and is then drawn toward the vessel 1 and brought into close contact with the open end 1a. Under this state, the operating rod is inserted through the recess 12a of the lid member 12 to place the wafer support at a desired position. Then, the lid member 12 is returned to its initial position, and another lid member 11 is brought into close contact with the open end 1a. Under this state, a heat treatment is carried out. According to this constitution, the lid member 11 or 12 is in close contact with the open end 1a at all times except when the wafer suppor is inserted. Therefore, the outside cold air is prevented from flowing into the vessel, so that the uniformity of the distribution of temprature inside the oven is improved. |
