Abstract: A vertical boat for holding a plurality of semiconductor wafers comprising two end members (2) positioned at the top and the bottom of the vertical boat, and a plurality of support members (3,4,5,6,104) vertically mounted on the end members (2) for supporting the wafers, wherein each support member (3,4,5,6,104) is formed by a plate-like member having a series of slits (9,10,7,8,108) formed thereon in such a manner that a plurality of support arms are defined by the slits (9,10,7,8,108) at a predetermined interval, each support arm having a support projection (11,12,13,14,112) formed at the end thereof, and wherein the inner portions (P) of the wafer (1) is to be supported by the support projections (11,12,13,14,112) whereas the periphery of the wafer (1) does not contact the arms of the support members (3,4,5,6,104).