FIGS. 11A and 11B are views illustrating temperature reproducibility of the first heat treatment by the heat treatment apparatus having the first partitions 70 and 72. FIG. 11A is a graph which illustrates a change over time in the measured temperature in the area CB in the space S, and time is illustrated on the horizontal axis, and temperature [□] is illustrated on the vertical axis. FIG. 11B is a graph which illustrates a change over each run in the measured temperature at time tm1 in FIG. 11A, and the number of runs is illustrated on the horizontal axis, and temperature [□] at time tm1 is illustrated on the vertical axis. Further, a plurality of solid lines in FIG. 11A illustrate the result for each run.

As illustrated in FIGS. 11A and 11B, when the first heat treatment is performed using the heat treatment apparatus having the first partitions 70 and 72, it can be seen that the temperature fluctuation hardly occurs at each run in the carry-in step. Meanwhile, as illustrated in FIG. 11A, it can be seen that the temperature fluctuation slightly occurs at each run after the carry-in step (see the circle indicated by broken lines).