Vertical boat and a method for making the same

A vertical boat for supporting a plurality of semiconductor wafers, each wafer having a peripheral portion and an inner portion therearound, the boat having a top portion and a bottom portion, comprising:

• two end members p1aced at the top portion and the bottom portion of the vertical boat;
• and
• a plurality of support members vertically extending between the end members for supporting the wafers,
• each of the support members being a plate-like member having a series of slits formed at a predetermined interval thereon,
• a plurality of support arms being defined by the slits, the support arms having support projections in such a manner that the inner portion of the wafer contacts and is supported by the support projections whereas the peripheral portion of the wafer does not contact the support projections and the arms of the support members wherein
• the inner portion of the wafer to be supported by the support projections ranges from a center of the wafer by 50%-90% of the radius of the wafer,
• the vertical boat is made of a material selected from a group consisting of silica glass, silicon carbide, carbon, monocrystal silicon, polycrystal silicon, and silicon carbide impregnated with silicon, and
• the support arms and the support projections of the support members are integral with each other so as to constitute a monoblock body.