Silicon seed rod assembly of polycrystalline silicon, method of forming the same, polycrystalline silicon producing apparatus, and method of producing polycrystalline silicon

Abstract

A silicon seed rod assembly used for producing polycrystalline silicon by means of a vapor deposition method includes two rod-shape silicon seed rods; and a silicon connection member bridging the silicon seed rods, wherein an opening-end peripheral edge of a through-hole on one side surface of the connection member is sharper than that on the other side surface thereof, and an opening-end peripheral surface on the one side surface thereof is formed into a flat contact surface disposed in a direction perpendicular to a perforation direction of the through-hole, and wherein a upper end portion of the silicon seed rod is inserted into the through-hole so that the contact surface comes into contact with the support surface of the silicon seed rod.

1 : A silicon seed rod assembly used for producing polycrystalline silicon by means of a vapor deposition method, comprising:
 two rod-shaped silicon seed rods; and   a silicon connection member bridging the silicon seed rods,   wherein a width of an upper end portion of each silicon seed rod is smaller than that of a main body portion thereof,   wherein a step portion formed between the upper end portion and the main body portion is provided with a support surface disposed in a direction perpendicular to a longitudinal direction of the upper end portion,   wherein the connection member is provided with a through-hole into which the upper end portion is inserted,   wherein an opening-end peripheral edge of the through-hole on one side surface of the connection member is sharper than that on the other side surface thereof, and an opening-end peripheral surface on the one side surface thereof is formed into a flat contact surface disposed in a direction perpendicular to a perforation direction of the through-hole, and   wherein the upper end portion is inserted into the through-hole so that the contact surface comes into contact with the support surface of the silicon seed rod.   
   
   
       2 . The silicon seed rod assembly according to  claim 1 , wherein the connection member includes an inclined surface of which a width gradually decreases from the downside to the upside. 
   
   
       3 . A method of forming a silicon seed rod assembly which is used for producing polycrystalline silicon by means of a vapor deposition method and includes two rod-shape silicon seed rods and a silicon connection member bridging the silicon seed rods, comprising the steps of:
 forming an upper end portion, of which a width is smaller than that of a main body portion, at an upper end of each silicon seed rod;   forming a support surface at a step portion between the upper end portion and the main body portion so as to be disposed in a direction perpendicular to a longitudinal direction of the upper end portion;   forming a through-hole by perforating the connection member from one side surface thereof by means of a drill in a direction perpendicular to the one side surface; and   inserting the upper end portion into the through-hole so that the one side surface comes into contact with the support surface of the silicon seed rod.   
   
   
       4 . A polycrystalline silicon producing apparatus comprising:
 the silicon seed rod assembly according to  claim 1  provided in a reaction furnace,   wherein at least a pair of electrodes is provided in a bottom portion in the reaction furnace, and end portions, disposed on the opposite side of the connection member, of both silicon seed rods of the silicon seed rod assembly are supported by the electrodes, respectively.   
   
   
       5 . A method of producing polycrystalline silicon comprising the steps of:
 forming a silicon seed rod assembly by uprightly supporting silicon seed rods by a pair of electrodes, respectively, disposed in a bottom portion in a reaction furnace and by providing a silicon connection member between upper end portions of the silicon seed rods;   heating the silicon seed rods by supplying current to the electrodes;   reacting the raw gas supplied to the reaction furnace; and   depositing polycrystalline silicon on surfaces of the silicon seed rods,   wherein the step of forming the silicon seed rod assembly includes the steps of:   forming an upper end portion, of which a width is smaller than that of a main body portion, at an upper end of each silicon seed rod and forming a support surface at a step portion between the upper end portion and the main body portion so as to be disposed in a direction perpendicular to a longitudinal direction of the upper end portion;   forming a through-hole by perforating the connection member from one side surface thereof by means of a drill in a direction perpendicular to the one side surface; and   inserting the upper end portion into the through-hole so that the one side surface comes into contact with the support surface of the silicon seed rod in a state where the silicon seed rods are supported by the electrodes provided in the reaction furnace, respectively.   
   
   
       6 . A polycrystalline silicon producing apparatus comprising:
 the silicon seed rod assembly according to  claim 2  provided in a reaction furnace,   wherein at least a pair of electrodes is provided in a bottom portion in the reaction furnace, and end portions, disposed on the opposite side of the connection member, of both silicon seed rods of the silicon seed rod assembly are supported by the electrodes, respectively.