A method for producing and classifying polycrystalline silicon. The method includes producing polycrystalline silicon rod within a reaction space of a gas phase deposition reactor by introducing a reaction gas, which in addition to hydrogen contains silane and/or at least one halosilane. Once produced, the polycrystalline silicon rod is extracted from the reactor, and at least one two-dimensional and/or three-dimensional image is generated of at least one partial region of the polycrystalline silicon rod or of at least one silicon chunk created. At least one analysis region is selected per generated image and at least two surface-structure indices per analysis region are generated by using image processing methods, each of which is generated using a different image processing method. The surface-structure indices are combined to form a morphology index.

A method for producing and classifying polycrystalline silicon. The method includes producing polycrystalline silicon rod within a reaction space of a gas phase deposition reactor by introducing a reaction gas, which in addition to hydrogen contains silane and/or at least one halosilane. Once produced, the polycrystalline silicon rod is extracted from the reactor, and at least one two-dimensional and/or three-dimensional image is generated of at least one partial region of the polycrystalline silicon rod or of at least one silicon chunk created. At least one analysis region is selected per generated image and at least two surface-structure indices per analysis region are generated by using image processing methods, each of which is generated using a different image processing method. The surface-structure indices are combined to form a morphology index.

A plate-shaped sample with a cross-section perpendicular to a radial direction of a polycrystalline silicon rod as a principal surface is sampled from a region from a center (r=0) of the polycrystalline silicon rod to R/3. Then, the sample is disposed at a position at which a Bragg reflection from a (111) Miller index plane is detected. In-plane rotation with a rotational angle φ on the sample is performed with a center of the sample as a rotational center such that an X-ray irradiation region defined by a slit performs φ-scanning on the principal surface of the sample to obtain a diffraction chart indicating dependency of a Bragg reflection intensity from the (111) Miller index plane on a rotational angle of the sample. A ratio (S.sub.p/S.sub.t) between an area S.sub.p of a peak part appearing in the diffraction chart and a total area S.sub.t of the diffraction chart is calculated.

A plate-shaped sample with a cross-section perpendicular to a radial direction of a polycrystalline silicon rod as a principal surface is sampled from a region from a center (r=0) of the polycrystalline silicon rod to R/3. Then, the sample is disposed at a position at which a Bragg reflection from a (111) Miller index plane is detected. In-plane rotation with a rotational angle φ on the sample is performed with a center of the sample as a rotational center such that an X-ray irradiation region defined by a slit performs φ-scanning on the principal surface of the sample to obtain a diffraction chart indicating dependency of a Bragg reflection intensity from the (111) Miller index plane on a rotational angle of the sample. A ratio (S.sub.p/S.sub.t) between an area S.sub.p of a peak part appearing in the diffraction chart and a total area S.sub.t of the diffraction chart is calculated.

The present invention decreases the impurity concentration of polycrystalline silicon to be produced. An apparatus (1) for producing polycrystalline silicon (S1) includes: a reactor (10) that contains a raw material gas (G1) for silicon deposition; a feed pipe (20) that forms a feed channel for feeding the raw material gas (G1) into the reactor (10), the feed pipe (20) including an inflow port (111) which is formed in the reactor (10) and through which the raw material gas (G1) flows in; and a filter (30) for removing impurities which have mixed in the raw material gas (G1), the filter (30) being provided in the feed channel.

The present invention decreases the impurity concentration of polycrystalline silicon to be produced. An apparatus (1) for producing polycrystalline silicon (S1) includes: a reactor (10) that contains a raw material gas (G1) for silicon deposition; a feed pipe (20) that forms a feed channel for feeding the raw material gas (G1) into the reactor (10), the feed pipe (20) including an inflow port (111) which is formed in the reactor (10) and through which the raw material gas (G1) flows in; and a filter (30) for removing impurities which have mixed in the raw material gas (G1), the filter (30) being provided in the feed channel.

In the silicon core wire according to a first aspect of the present invention, a male thread part formed at one end of a first thin silicon rod and a female thread part formed at one end of a second thin silicon rod may be screwed together and fastened. In the silicon core wire according to a second aspect of the present invention, a thread part formed at one end of a first thin silicon rod and a thread part formed at one end of a second thin silicon rod may be screwed together and fastened via an adapter with thread parts formed at both ends.

In the silicon core wire according to a first aspect of the present invention, a male thread part formed at one end of a first thin silicon rod and a female thread part formed at one end of a second thin silicon rod may be screwed together and fastened. In the silicon core wire according to a second aspect of the present invention, a thread part formed at one end of a first thin silicon rod and a thread part formed at one end of a second thin silicon rod may be screwed together and fastened via an adapter with thread parts formed at both ends.

Polycrystalline silicon is produced in a chemical vapour deposition reactor, wherein, outside the reactor at at least one position on at least one reactor component, vibrations of the reactor are measured using a measurement device and optionally recorded. The vibrations may be used to identify rod fall over and other events occurring within the reactor.

An apparatus for manufacturing a polysilicon rod comprising: a core wire 1 on which polysilicon is deposited; a core wire electrode 60 provided to penetrate a bottom plate 80; an adjustment member 10 provided between the silicon core wire 1 and the core wire electrode 60, and movable with respect to the bottom plate 80; and a cooling part capable of cooling the adjustment member 10.