NOVELTY - The apparatus comprises a reaction pipe comprising silicon particles, a unit (600) configured to supply flowing gas to the silicon particles provided in the reaction pipe, a gas outlet configured to exhaust gas generated in the reaction pipe, a pressure sensor arranged in the gas outlet and the flowing-gas supply unit, and a particle outlet configured to exhaust polycrystal silicon formed in the reaction pipe outside, when a pressure measured by the pressure sensor is a reference pressure value or more.    USE - The apparatus is useful for manufacturing polycrystal silicon, which is useful for semiconductor device or a solar cell and for a precision functioned device or a precision part of a highly integrated micro system.    ADVANTAGE - The apparatus ensures efficient, automatic and economic manufacture of the polycrystal silicon with high quality, purity, stability and productivity and without carbon impurities.    DETAILED DESCRIPTION - The apparatus comprises a reaction pipe comprising silicon particles, a unit (600) configured to supply flowing gas to the silicon particles provided in the reaction pipe, a gas outlet configured to exhaust gas generated in the reaction pipe, a pressure sensor arranged in the gas outlet and the flowing-gas supply unit, and a particle outlet configured to exhaust polycrystal silicon formed in the reaction pipe outside, when a pressure measured by the pressure sensor is a reference pressure value or more. The polycrystal silicon formed in the reaction pipe is exhausted outside, when a difference between a first pressure measured in the flowing gas supply unit and a second pressure measured in the gas outlet is a reference pressure value or more. The particle outlet is operated to exhaust the polycrystal silicon outside, when the difference between the first pressure and the second pressure is the reference pressure value or more. One of silicon, silica, quartz and silicon nitride is lined on an inner wall of the reaction pipe, when the reaction pipe is formed of a carbon containing material. The apparatus further comprises a lower part having the flowing-gas supply unit. The lower part comprises a lower plate, a first plate, a second plate and a third plate that are multilayered sequentially. Each of the second and third plates comprises unit-plates. An insulation ring is provided to cover a rim of the second plate. An end of the second plate is spaced apart a predetermined distance from a surface of the lower plate. A predetermined area of the first plate is located between the lower plate and an end of the second plate. An INDEPENDENT CLAIM is included for a method of manufacturing polycrystal silicon.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of a polycrystal silicon manufacturing apparatus.    Head (100)    First body part (200)    First reaction pipe (250)    Second body part (300)    Flowing-gas supply unit (600)    Heater. (700)