Patent ID: 8469703

Claim:
A vertical boat for heat treatment comprising: a plurality of supporting columns, each supporting column extending vertically between an upper end and a lower end thereof, a pair of plate members, including an upper plate member coupled to the upper ends of the supporting columns and a lower plate member coupled to the lower ends of the supporting columns, the supporting columns comprising a plurality of slits spaced apart and a plurality of supporting parts interposed between the slits for horizontally supporting substrates to be treated, each supporting part being formed on the supporting column and having a curvilinear shape, and a plurality of auxiliary supporting members, each auxiliary supporting member being removably attached to one and only one corresponding supporting part, each auxiliary supporting member having a lower surface and a downward extension that contacts an upper surface of the corresponding supporting part when the auxiliary supporting member is attached to the corresponding supporting part and an upper surface for contacting one of the substrates, wherein the lower surface of a first auxiliary supporting member of the plurality of auxiliary supporting members is shaped to accommodate the shape of the corresponding supporting part such that the upper surface of the first auxiliary support member is at a predetermined inclination when the first auxiliary supporting member is attached to the corresponding supporting part of the first auxiliary supporting member.