The invention discloses a
processing technology for preparing
single crystal silicon by the
Czochralski method, which comprises the following steps:
necking growth: when the temperature of the
silicon melt is stabilized to a certain temperature, the
seed crystal is immersed in the
silicon melt, and the
seed crystal is Increase the pulling speed at a certain rate to reduce the
diameter of the
seed crystal to 3-7mm; shoulder growth: after the
necking growth is completed, reduce the
crucible temperature and pulling speed, adjust the
crucible rotation speed and
crystal rotation speed, and increase the
crystal to the required
diameter; equal-
diameter growth: after the shoulder growth is completed, adjust the
crucible temperature, pulling speed, crucible rotation speed and
crystal rotation speed, so that the diameter of the
ingot is maintained between plus and minus 2mm; the present invention adds pure
boron to the
single crystal silicon
raw material, The
mass ratio of pure
boron to
monocrystalline silicon raw materials is 5%-15%, so that the resistivity of
monocrystalline silicon can reach 300Ω / CM, and the radial uniformity of resistivity is within 3%; reduce the
oxygen content in silicon melt It effectively inhibits the entry of
oxygen from the silicon melt into the silicon crystal, improves work efficiency, and reduces the
oxygen content of the silicon crystal.