To improve a heat treatment apparatus used in a calcination process when providing an electrode on the front and back of a silicon wafer, and to realize an ideal temperature profile in calcination.

The heat treatment apparatus includes a heat treatment part, and the heat treatment part includes a shelf-like member (installation part and heat source part) 11 inside a heat insulating housing. The shelf-like member 11 has shelf members 16a-16g in 7 stages, and the inside of the shelf member 16b is partitioned into upper and lower unit chambers 25 and 26. In the upper and lower unit chambers 25 and 26, 9 halogen lamps 27 for a row and 36 halogen lamps 28 for a column are respectively arrayed in a crisscross lattice shape to configure a heat source unit 35. The illuminance of each heat source unit 35 is individually controlled to make the illuminance of upper and lower heat source unit groups 47 be different or change the illuminance of the upper side heat source unit 35 of one stage and the upper side heat source unit 35 of another stage as well. Also, the illuminance can be changed during lighting.