# Polysilicon

Ultra-pure silicon (nine to eleven nines) made from metallurgical silicon; the base of solar wafers and chips, over 90% made in China.

Source page: https://www.materialinsights.org/chemicals/polysilicon/

Specialty chemicals · Energy-transition chemicals · No. 69

- Product family
- Feedstock: Minerals and salts
- about 1.4 Mt produced in 2025 (derived: China 1.32 Mt, down 28.4% from 2024, plus roughly 0.1 Mt outside China, indicative); world output was about 1.95 Mt in 2024; nameplate capacity above 3.2 Mt
- 35.0 t CO₂e per t
- HS 280461
 Specialty chemicals · Energy-transition chemicals · Foundation · Matter

Solar panels start as silicon purified to nine nines, and China built enough plants to make it twice over.

Chart: Illustration: Polysilicon

##### Where it comes from

Chart: Map of where it comes from

Silicon metal from quartz is turned into trichlorosilane gas, distilled, and deposited back as silicon on hot rods at about 1,100 C.

##### Three things to know

1. About 94% of polysilicon goes into n-type solar wafers; chips take only about 4% but need even purer, 10-11 nines material.
2. Siemens reactors burn about 48 kWh per kg, while newer fluidised-bed granules need only 11-20 kWh.
3. India makes no polysilicon, yet ALMM-listed domestic wafers become mandatory for covered projects from 1 June 2028.

##### The journey

1. 1 **Quartz**Reduced with carbon in arc furnaces
2. 2 **Silicon metal**98.5-99.5% pure metallurgical silicon
3. 3 **Trichlorosilane**Reacted with HCl, then distilled ultra-pure
4. 4 **Deposition**Grown on hot rods or granules
5. 5 **Polysilicon**Nine to eleven nines pure
6. 6 **Wafers**Sliced for solar cells and chips
 Covered in [Making electricity: thermal, nuclear, hydro, wind and solarEnergy](https://www.materialinsights.org/learn/energy/making-electricity/)[Using energy: food, materials, mobility and buildingsEnergy](https://www.materialinsights.org/learn/energy/using-energy/)

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## Other sections

- [Overview](https://www.materialinsights.org/chemicals/polysilicon/overview/index.md)
- [Correlation](https://www.materialinsights.org/chemicals/polysilicon/correlation/index.md)
- [Production route](https://www.materialinsights.org/chemicals/polysilicon/routes/index.md)
- [Production](https://www.materialinsights.org/chemicals/polysilicon/production/index.md)
- [Feedstocks](https://www.materialinsights.org/chemicals/polysilicon/feedstocks/index.md)
- [Cycles](https://www.materialinsights.org/chemicals/polysilicon/cycles/index.md)
- [Trading](https://www.materialinsights.org/chemicals/polysilicon/trading/index.md)
- [Movement](https://www.materialinsights.org/chemicals/polysilicon/movement/index.md)
- [Regulation](https://www.materialinsights.org/chemicals/polysilicon/regulation/index.md)
- [Characteristics](https://www.materialinsights.org/chemicals/polysilicon/characteristics/index.md)
- [Emissions](https://www.materialinsights.org/chemicals/polysilicon/emissions/index.md)
- [Relationships](https://www.materialinsights.org/chemicals/polysilicon/links/index.md)