The invention provides an apparatus for drawing a crystalline sheet from a melt. The apparatus may include a crucible configured to contain the melt and having a dam structure, where the melt comprises an exposed surface having a level defined by a top of the dam structure. The apparatus may further include a support apparatus disposed within the crucible and having an upper surface, wherein the crystalline sheet is maintained flush with the exposed surface of the melt when drawn over the support apparatus, and may include a melt-back heater directing heat through the upper surface of the support apparatus to partially melt the crystalline sheet when the crystalline sheet is drawn over the support apparatus.