Reaction furnace for producing polycrystalline silicon, apparatus for producing polycrystalline silicon, method for producing polycrystalline silicon, and polycrystalline silicon rod or polycrystalline silicon ingot

Patent metadata

Field	Value
Publication number	US-10870581-B2
Application number	US-202016845779-A
Country	US
Kind code	B2
Filing date	Apr 10, 2020
Priority date	Sep 4, 2014
Publication date	Dec 22, 2020
Grant date	Dec 22, 2020

Abstract

A reaction furnace for producing a polycrystalline silicon according to the present invention is designed so as to have an in-furnace reaction space in which a reaction space cross-sectional area ratio (S=[S0−SR]/SR) satisfies 2.5 or more, which is defined by an inner cross-sectional area (So) of a reaction furnace, which is perpendicular to a straight body portion of the reaction furnace, and a total sum (SR) of cross-sectional areas of polycrystalline silicon rods that are grown by precipitation of polycrystalline silicon, in a case where a diameter of the polycrystalline silicon rod is 140 mm or more. Such a reaction furnace has a sufficient in-furnace reaction space even when the diameter of the polycrystalline silicon rod has been expanded, and accordingly an appropriate circulation of a gas in the reaction furnace is kept.

First claim

The invention claimed is:

1. A reaction furnace for producing a polycrystalline silicon by a Siemens method, wherein
the reaction furnace has an in-furnace reaction space in which when an inner cross-sectional area of the reaction furnace, which is perpendicular to a straight body portion of the reaction furnace, is represented by S 0 , and a total sum of cross-sectional areas of polycrystalline silicon rods that are grown by precipitation of the polycrystalline silicon onto at least one pair of silicon core wires in an inverted U shape, which are arranged in the reaction furnace, is represented by S R =ΣS i ,
a reaction space cross-sectional area ratio that is defined by S=[S 0 −S R ]/S R satisfies 2.5 or more, based on a final diameter, which is 140 mm or more, of the polycrystalline silicon rod.

2. An apparatus for producing a polycrystalline silicon, comprising the reaction furnace according to claim 1 .

3. The reaction furnace, according to claim 1 , further comprising a source gas supply nozzle for supplying source gas in the in-furnace reaction space, wherein
the source gas supplied from the source gas supply nozzle is controlled such as a composition ratio in wt % between trichlorosilane (TCS) and silicon tetrachloride (STC) in an exhaust gas to 1.2 or more, until a diameter of a polycrystalline silicon rod that is growing reaches 100 mmϕ.

Assignees

• Shinetsu Chemical Co

Inventors

• Netsu Shigeyoshi
• Hoshino Naruhiro
• Okada Tetsuro
• Saito Hiroshi

Classifications

• C01B33/035 Primary

  by decomposition or reduction of gaseous or vaporised silicon compounds in the presence of heated filaments of silicon, carbon or a refractory metal, e.g. tantalum or tungsten, or in the presence of heated silicon rods on which the formed silicon is deposited, a silicon rod being obtained, e.g. Siemens process · CPC title

• B01J19/087

  employing electric or magnetic energy · CPC title

• B01J2219/0801

  Controlling the process · CPC title

• B01J2219/0803

  employing electric or magnetic energy · CPC title

• C23C16/46

  characterised by the method used for heating the substrate (C23C16/48, C23C16/50 take precedence) · CPC title