What is Polysilicon?

Polysilicon is a hyper pure form of silicon and is the earth’s second most abundant element. Due to its semiconductor-like material properties, polysilicon is used as feedstock material in most solar energy applications.

Polysilicon is an initial building block for the process of manufacturing silicon based Solar PV. The process for making silicon based Solar PV modules is as follows:

  1. Polysilicon is melted at extremely high temperatures into a liquid state and a silicon crystal ingot is grown from the resulting melt.
  2. The ingots are squared and sliced very thinly into wafers.
  3. The wafers are processed into solar cells to convert sunlight into electricity.
  4. Solar cells are strung together and framed into a module.
  5. Modules are then integrated into a system and ready for use by the end-user!

Polysilicon can be manufactured in two forms depending on the technology used for production, chunk polysilicon or granular polysilicon, with advantages and disadvantages alike.

AEP’s fluidized bed reactor technology produces polysilicon in the granular BB form which has distinct benefits over chunk polysilicon.