Polycrystalline silicon, fz single crystal silicon, and method for producing the same

Abstract

When FZ single crystal silicon is produced from polycrystalline silicon, which is synthesized by the Siemens method followed by being subjected to thermal treatment and includes crystal grains having a Miller index plane <111> or <220> as a principal plane and grown by the thermal treatment, and in which the X-ray diffraction intensity from either of the Miller index planes <111> and <220> after the thermal treatment is 1.5 times or less the X-ray diffraction intensity before the thermal treatment, as raw material, disappearance of crystal lines in the step of forming an FZ single crystal is markedly prevented.

Dependencies are inferred from the claim text.