Polycrystalline silicon fragment, method for manufacturing polycrystalline silicon fragment, and polycrystalline silicon block fracture device

• US 10,307,763 B2
• Filed: 10/09/2015
• Issued: 06/04/2019
• Est. Priority Date: 10/14/2014
• Status: Active Grant

• Current Assignee: Tokuyama Corporation
• Original Assignee: Tokuyama Corporation
• Inventors: Kawaguchi, Kazuhiro, Fujii, Masami, Uchida, Sho, Kondo, Manabu, Mito, Yoshifumi, Yoshimatsu, Nobuaki
• Primary Examiner(s): Le, Hoa (Holly)
• Application Number:
  US15/518,637
• Publication Number:
  US 20170239666A1
• Time in Patent Office: 1,334 Days
• CPC Class Codes: B02C 1/04 with single-acting jaws
• CPC Class Codes: B02C 23/10 with separator arranged in discharge path of crushing or disintegrating zone
• CPC Class Codes: B02C 23/30 the applied gas acting to effect material separation B02C23/34 takes precedence
• CPC Class Codes: C01B 33/02 Silicon forming single crystals or homogeneous polycrystalline material with defined structure C30B
• CPC Class Codes: C01P 2004/60 Particles characterised by their size
• CPC Class Codes: C01P 2006/80 Compositional purity
• CPC Class Codes: C30B 15/02 adding crystallising materials or reactants forming it in situ to the melt

Abstract

Polycrystalline silicon fragments obtained by fracturing polycrystalline silicon blocks wherein a content ratio of polycrystalline silicon powder having a particle size of 500 to 1000 μm is 0.1 to 40 ppmw.

Claims

1. A polycrystalline silicon fragment obtained by fracturing a polycrystalline silicon block which is not carried out with a wet chemical cleaning using acid, comprising:

i) 90 wt % or more of said polycrystalline silicon fragment has the particle size of 4 to 60 mm;

ii) a content ratio of polycrystalline silicon powder having the particle size of 500 to 1000 μ

m is 1 to 30 ppmw;

iii) a content ratio of the silicon dust having the particle size of less than 500 μ

m is 10 to 60 ppmw, and

iv) a metal of a surface contamination including at least one metal selected from the group consisting of Na, Cr, Fe, Ni, Cu, Zn, Co, and W is 3 to 15 ppbw.

2. A polycrystalline silicon fragment obtained by fracturing a polycrystalline silicon block which is not carried out with a wet chemical cleaning using acid, comprising:

i) 90 wt % or more of said polycrystalline silicon fragment has the particle size of 2 to 40 mm;

ii) a content ratio of the polycrystalline silicon powder having the particle size of 500 to 1000 μ

m is 2 to 40 ppmw;

iii) a content ratio of the silicon dust having the particle size of less than 500 μ

m is 20 to 140 ppmw, and

iv) a metal of a surface contamination including at least one metal selected from the group consisting of Na, Cr, Fe, Ni, Cu, Zn, Co, and W is 15 to 30 ppbw.

3. A polycrystalline silicon fragment obtained by fracturing a polycrystalline silicon block which is not carried out with a wet chemical cleaning using acid, comprising:

i) 90 wt % or more of said polycrystalline silicon fragment has the particle size of 20 to 90 mm;

ii) a content ratio of the polycrystalline silicon powder having the particle size of 500 to 1000 μ

m is 0.5 to 25 ppmw;

iii) a content ratio of the silicon dust having the particle size of less than 500 μ

m is 5 to 50 ppmw, and

iv) a metal of a surface contamination including at least one metal selected from the group consisting of Na, Cr, Fe, Ni, Cu, Zn, Co, and W is 2 to 8 ppbw.