| 摘要 |
PROBLEM TO BE SOLVED: To prevent the formation of unstable air flow along wafer edges to exert a detriment to the heat treatment of the wafer edges. SOLUTION: A purging gas supply port 72 is provided at the middle of the top plate 70 of a cover 61. Exhaust ports 81 are provided on the side walls 61a of the cover 61, positioned external to a wafer W on a heating plate 63 and higher than the wafer W. Inside the cover 61, a first and second gas flow guide 73, 74 are provided; inside the side walls 61a, an exhaust duct 80 communicating with the exhaust ports 81 is formed; and, on the top plate 70, an impurity collecting section 87 communicating with the exhaust duct 80 is provided. During a heat treatment, the purging gas is introduced from the gas supply port 72 in the upper part of the treatment chamber S, passes through the first and second gas flow guide 73, 74, and then discharged from the exhaust ports 81 positioned higher than the wafer W at the side of the treatment chamber S. Thus the gas does not travel near the surface of the wafer W, adverse effect due to unstable currents is prevented. COPYRIGHT: (C)2004,JPO |
