Silicon dioxide (SiO2) is the most abundant mineral in the earth's crust. It occurs naturally
in the form of sand and quartz. Oxygen is removed from Quartz rock by reduction with
carbon in an electric arc furnace to produce Metallurgical Grade Silicon (MG-Si) at
around 98% purity.
Polysilicon hydrochlorination process starts with the introduction of hydrogen (H2),
metallurgical grade silicon (MG-Si) and silicon tetrachloride (STC) into a fluidized bed
reactor, in which hydrogenation of STC and transformation of MG-Si to trichlorosilane,
known as TCS (SiHCl3) (TCS) takes place.
TCS goes through several purification steps and then reacts with H2 in a chemical
vapour deposition (CVD) reactors, deposits onto high grade Polysilicon rods that are
crushed into chunks, separated in deferent sizes and packaged.
Polysilicon chunks are casted into multicrystalline blocks or submitted to a
recrystallization process to grow single crystal ingots.
The blocks and/or ingot are shaped and sliced into very thin wafers using a wire saw,
ensuring precise and even thickness. They are then chemically cleansed to remove any
unwanted surface elements.
The wafers are then processed into solar cells to create the sunlight absorption and
electricity conversion functionality.
Hundreds of solar cells are combined into complex clusters to increase efficiency levels.
The resulting solar panels can range anywhere from a square foot to hundreds of square