Polysilicon Production Plant Equipment
Two key pieces of capital equipment required for a polysilicon production plant are Chemical Vapor Deposition (CVD) reactors and Thermal converters.  These are long lead time items that should be purchased early in the procurement process to ensure their availability during the construction of the polysilicon production plant.

Poly Plant Project, Inc. does not manufacture or supply this equipment but PPP does provide its customers with recommendations of equipment and will introduce suppliers of this critical polysilicon production plant equipment.

Chemical Vapor Deposition (CVD) Reactors

The method for producing polysilicon material or feedstock is often referred to as the Siemens process.  The Siemens process uses a Chemical Vapor Deposition or silicon deposition reactor and trichlorosilane (TCS) gas. 

These CVD reactors have a bell jar covering a chamber in which gasses at high temperature and controlled pressure undergo chemical reactions.  These chemical reactions result in the growth of a thin film on a solid surface (the filament) inside the reactor.  The ultimate product is a U-shaped rod of polysilicon material.

The quantity of CVD reactors is determined by the capacity of the polysilicon production plant.  CVD reactors can have a Metric Ton per Year (MTY) capacity up to and exceeding 150 tons.   Using 150 tons as a reference, a poly plant with a capacity of 2500 MTY would require about 16-18 CVD reactors.
 
Thermal Converters

By-product gases recovery and recycle systems are designed for the collection, separation, and purification of by-product gases and convert silicon tetrachloride to trichlorosilane.  Thermal converters are used for the conversion of STC to TCS. This system collects by-product gases (chlorosilanes, silicon tetrachloride, hydrogen, hydrogen chloride), separate the gases and purify for re-use.

In regard to the quantity of Thermal Converters required, the ratio is typically one Thermal Converter for every two deposition reactors.

Keywords:  Chemical Vapor Deposition, CVD, polysilicon deposition reactors, Siemens process, silicon deposition reactor, thermal converter, trichlorosilane, TCS, silicon tetrachloride, STC, gas conversion