The invention discloses an N-type hanging polycrystal material resistivity grading method, which comprises the following operation steps: in a straight pulling
single crystal process, especially when an N-type circulating material is processed, the resistivity of the material is known and controlled, the resistivity is the measure of the hindering degree of the material to current flow and is influenced by the
doping concentration and the temperature, and the resistivity of the material is determined according to the influence of the
doping concentration and the temperature. And estimating the resistivity when the corresponding residual material amount grows through the initial head resistivity, the
doping concentration and the segregation coefficient in the growth process. According to the resistivity grading method for the N-type hanging polycrystal material, the resistance value range of the N-type hanging polycrystal material is calibrated and divided according to the
crucible remaining quantity of an output furnace platform through segregation theory measurement and calculation, the
impurity concentration corresponding to the residual quantity of the output furnace platform of the hanging polycrystal material is calculated, and the resistivity corresponding to the current concentration is converted to obtain the
tail resistance of the hanging polycrystal material; and the
resistor in the range of the suspended polycrystal material is reversely pushed, so that the suspended polycrystal material can be accurately graded, and the resistivity
concentration ratio is improved.