Abstract: An apparatus for holding a plurality of semiconductor wafers during heat treatment of the wafers in a furnace, which apparatus comprises a plurality of support members or rails extending essentially vertically between a top and bottom plate. At least two of the support members are located toward the front of the carrier where the wafers are inserted, and at least one support member is located toward the back of the carrier. A first plurality of slats is attached to one of the front support members and to a back support member such that the space between the top surface of one slat and the bottom surface of the next higher adjacent slat forms a slot for receiving a portion of a semiconductor wafer. A second plurality of slats is attached to another front support member and to a back support member to form corresponding slots on another side of the carrier for receiving another portion of a semiconductor wafer.