Silicon core wire for depositing polycrystalline silicon and production method therefor
AssigneeTokuyama Corporation
InventorsJunya Sakai, Seiji Katou, Makoto Kamada, Miki Emoto
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Abstract
A silicon core wire for depositing polycrystalline silicon is formed in a gate shape and includes a pair of vertical rod portions and a horizontal portion laterally connecting upper ends of the vertical rod portions, in which ends of the vertical rod portions and the horizontal portion are joined by welding, and a corner junction has a surface metallic concentration of 1 ppbw or less, more specifically, with an iron concentration of 0.2 ppbw or less, a chromium concentration of 0.1 ppbw or less, a nickel concentration of 0.05 ppbw or less, and a titanium concentration of 0.2 ppbw or less.
Claims12
A silicon core wire for depositing polycrystalline silicon formed in a gate shape, comprising:
- a pair of vertical rod portions;
- and
- a horizontal portion laterally connecting upper ends of the two vertical rod portions,
- wherein ends of the vertical rod portions and the horizontal portion are joined by welding, and a metallic concentration from a surface of a corner junction to a depth of 100 micrometers is 1 ppbw or less, and
- wherein in the metallic concentration from a surface of a corner junction to a depth of 100 micrometers, an iron concentration is 0.2 ppbw or less, a chromium concentration is 0.1 ppbw or less, a nickel concentration is 0.05 ppbw or less, and a titanium concentration is 0.2 ppbw or less.
Dependencies are inferred from the claim text.