Refining & Grade Specs

Silicon Refining Methods and Grade Specifications

The transformation of Silicon concentrate into refined products suitable for industrial use requires specialized metallurgical and chemical processes. Silicon is refined into 5 primary commercial forms, each serving specific end-use sectors.

Refining Processes

The primary refining and processing pathways for Silicon include:

1. Carbothermic reduction in submerged arc furnaces
2. Siemens process (polysilicon)
3. Fluidized bed reactor (FBR polysilicon)
4. Czochralski crystal growth (wafers)

Product Forms and Grade Specifications

Refined Silicon is available in the following commercial forms, each with specific purity requirements:

Quality Standards and Benchmarks

International standards for Silicon products are established by organizations such as ASTM International and various national standards bodies. Pricing is referenced against CRU / Argus (553 grade, Europe delivered) assessments. These standards define minimum purity levels, acceptable impurity limits, and testing methodologies that facilitate international trade.

Refining Capacity and Geography

Global refining capacity for Silicon is concentrated in a limited number of countries. China controls approximately 75% of primary production and plays a significant role in downstream refining. Efforts to diversify refining capacity are a key priority for governments seeking to reduce supply chain dependencies, particularly in the semiconductor chips and electronics sector.