Patent ID: 8741064
Filing Date: 2014-06-03
Classification: C21D,C23C,H01L

Abstract:
1. A heat treatment method in which a plurality of substrates to be treated is held by a substrate holder at predetermined vertical intervals, the substrate holder is carried into a heat treating furnace, and a predetermined heat treatment is performed on the substrates, the method comprising the steps of: forming a multi-plate unit to hold circumferential portions of two substrates under the condition that back surfaces of the two substrates face each other; holding a plurality of the multi-plate units by means of the substrate holder at a vertical interval larger than a distance between the front surface of one of the two substrates held by the multi-plate unit and the back surface of the other of the two substrates such that a first distance between one of a first pair of substrates that are vertically adjacent each other and have respective front surfaces facing each other and the other of the first pair of substrates is larger than a second distance between one of a second pair of substrates that are vertically adjacent each other and have respective back surfaces facing each other and the other of the second pair of substrates; and performing the predetermined heat treatment, wherein each of the multi-plate units has a first support ring and a second support ring, each of the first support rings being adapted to hold the substrate under the condition that the back surface of the substrate faces upward, each of the second support rings being adapted to hold the substrate under the condition that the front surface of the substrate faces upward.