NOVELTY - A low-defect high-throughput polysilicon ingotting method involves placing silicon material into a crucible (6), closing the whole thermal field space of a resistance heater (3) and raising temperature to 1500 degrees C, heating the silicon material for 10 hours, when the pressure is 0.1-0.6 atm, at the same time, introducing inert protective gas or chemical material (14); providing local cooling at the crucible bottom part to form a transverse temperature gradient at the bottom of the crucible, resulting in lateral crystal growth to form large grain.    USE - As low-defect high-throughput polysilicon ingotting method (claimed) used to for solar cell used in solar photovoltaic applications.    ADVANTAGE - The method produces low-defect and provides high-throughput. The separated independent control of heater, reduces energy consumption to the utmost extent, but also enables convenient adjustment of long crystal interface, obtaining more flat the crystal growth interface and improves the crystal quality and solves the problem that the height of the ingot increase caused by the crystal stage radiating. Using supporting piece of unique design and cooling device of the local cooling, results in greatly increased crystal grain with reduced boundary, and reduces the dislocation and micro-defect.    DETAILED DESCRIPTION - A low-defect high-throughput polysilicon ingotting method involves mixing silicon material (550-750 kg) into a 480-650 mm crucible (6), closing the whole thermal field space, top part (2) of heater and side part (4) of the resistance heater (3) at the same time, raising temperature to 1500 degrees C, heating the silicon material for 10 hours, when the pressure is 0.1-0.6 atm, at the same time, introducing inert protective gas or chemical material via inlet (14); providing local cooling at the crucible bottom part resulting in nucleation of crystal at the initial part to form the transverse temperature gradient at the bottom of the crucible, resulting in lateral crystal growth to form large grain, during which the period of time is controlled to 2 hour. An INDEPENDENT CLAIM is included for a system for carrying low-defect high-throughput polysilicon ingotting method, comprising a upper heat preserving plate (1); heat insulating cover side wall (5) and lower heat insulating plate (9), within which is placed a graphite crucible (6) supported by a block (7); and a quartz crucible (12) supported by support rod (10); the crucible is heated by a heater (3) that is divided into upper part (2) and side part (4). The upper part of crucible is provided with a crucible cover plate (13) that is provided with an inert protective gas ingress pipe (14). The cooling device (8) is set under the supporting block having holes and the cooling device is provided with a cooling gas inlet pipe (11), supporting block of the local cooling.    DESCRIPTION OF DRAWING(S) - The figure shows view of the system used to form the polysilicon ingot.    Heat preservation board (1)    Top heater (2)    Resistant heater (3)    Lower side of the heater (4)    Side wall cover of heater (5)    Graphite crucible (6)    Supporting block (7)    Cooling device (8)    Heat preservation plate (9)    Support rod (10)    Cooling gas inlet pipe (11)    Quartz crucible (12)    Cover board (13)    Protective gas inlet pipe (14)