STEAM ANNEALING METHOD

PROBLEM TO BE SOLVED: To solve the problem of conventional high pressure annealing procedure in which a processed work is often spoiled with spotlike stains. SOLUTION: When the temperature (T) in a processing chamber 19 becomes higher by Δt than the saturation temperature (t) for the inner pressure of the processing chamber 19 after preheating (H1), heating means 25c and 25d are actuated to evaporate pure water by heating a pure water holding chamber 20 thus raising the saturation temperature (t) for the inner pressure of the processing chamber 19 and the saturation steam pressure (P) in the annealing chamber 19. After the saturation steam pressure (P), the saturation temperature (t) and the temperature (T) in the processing chamber 19 are settled at specified levels (H2), annealing work is started while sustaining the saturation temperature (t) and the saturation steam pressure (P) at constant levels. After ending the annealing work (H3), the T, t and P are returned gradually back to initial levels while sustaining the temperature (T) at a level higher by Δt than the saturation temperature (t). COPYRIGHT: (C)2005,JPO&NCIPI