Directional solidification (DS) is the main method for manufacturing multicrystalline Si ingots for solar cells.
From polysilicon to multicrystalline ingot
Firstly, Polisilicon chunks are charged in the crubile. Then the crucible are transferred into the Directional solidification system, after around 50 hours, the multicrystalline ingot is made.
Silicon charge in Crucible; Multicrystalline casting; Finished ingot.
From ingot to wafers
These large ingots are then sawn into smaller bricks as in Fig. (a) (b), and after chamfered the bricks are sliced into wafers. Wafers are generally square with sides in the 15–17 cm range.
(a)(b) Sawn into bricks; (c) Bricks are ground; (d) Chamfered, then (e) Sawn into wafers, (f) As-cut wafers.
