Polycrystalline silicon rods

PROBLEM TO BE SOLVED: To provide a polycrystalline silicon rod suitable as a raw material for single crystallization, when manufacturing a raw material for single-crystal silicon manufacturing from a polycrystalline silicon rod synthesized from monosilane.SOLUTION: A polycrystalline silicon rod grown with monosilane as a raw material has a crystal particle diameter, determined from an electron backscattering diffraction pattern which is obtained when a tabular specimen having a cross-section vertical to a radial direction as its principal plane is taken from an arbitrary part of the rod and is irradiated with electron beams on its principal plane, is in a range of 0.5 to 10 μm, and an average particle diameter in a range of 2 to 3 μm, and shows a good FZ,L% value. Further, a polycrystalline silicon rod having thermal diffusivity, measured on the principal plane of the tabular specimen, in a range of 75 to 85 mm/sec at 25±1°C, shows a good FZ,L% value and is appropriate as a raw material for single crystallization.SELECTED DRAWING: Figure 1A