PURPOSE: To avoid causing the film thickness nonuniformity or dopant concn. nonuniformity by adding a plate-like member for the gas intake to a boat and rotating it together with the boat to distribute a reactive gas uniformly between wafers.

CONSTITUTION: The end of a wafer 4 is inserted in grooves 5 of posts 1 to hold the wafer 4 with the posts 2, it is housed in a heat-treating furnace to execute the film forming process, doping process, heat treatment, etc. In the treatment, a rotary machine 15 is rotated to rotate a boat 2 together. plate-like members 3 are formed on the posts 2 at specified angle θ1 to the peripheral tangential direction of a disk-like member 1 to thereby positively take a reactive gas inwards in the disk-like member 1. Thus the reactive gas is enough and uniformly taken in between wafers 4, hence the film thickness nonuniformity or dopant concn. nonuniformity is resolved. The specified angle θ1 is pref. 10-80° for efficiently sending the reactive gas between the wafers.