Ingot & Wafer

To manufacture solar cells, thin wafers have to be produced from polysilicon. Initially, the polysilicon is crystallized to ingots: polysilicon blocks of multi-crystalline silicon or columns of mono crystalline silicon. These ingots are then cut into bricks, which are later cut into wafers.

centrotherm supplies Ingot Furnaces based on the vertical gradient directional solidification principle to manufacture ingots. Initially, along a process of heating, melting, annealing and cooling stages, the polysilicon chunks are melted to ingots in quartz crucibles. These ingots are then squared to identically sized bricks and subsequently cropped using diamond wire technology. Finally, these bricks are cut into thin silicon wafers.