Polycrystalline silicon fragment, method for manufacturing polycrystalline silicon fragment, and polycrystalline silicon block fracture device
AssigneeTokuyama Corporation
InventorsKazuhiro Kawaguchi, Masami Fujii, Sho Uchida, Manabu Kondo, Yoshifumi Mito, Nobuaki Yoshimatsu
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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.
Claims3
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 μm is 1 to 30 ppmw;
- iii) a content ratio of the silicon dust having the particle size of less than 500 μm 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.
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 μm is 2 to 40 ppmw;
- iii) a content ratio of the silicon dust having the particle size of less than 500 μm 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.
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 μm is 0.5 to 25 ppmw;
- iii) a content ratio of the silicon dust having the particle size of less than 500 μm 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.
Dependencies are inferred from the claim text.