Boron segregation control in silicon crystal ingots grown in Czochralski process

Boron-doped silicon single crystals of 207 mm diameter with various growing conditions are grown from a large amount of the melt in the cusp-magnetic Czochralski method, and the effects of growing parameters on dopant concentrations in the crystals are experimentally investigated. Equilibrium distribution coefficient of boron calculated by BPS model is 0.716. With the crystal rotation (ω) of 13 rpm and the crucible rotation of -0.5rpm, the effective distribution coefficient (ke) is 0.751 in zero magnetic strength and increases up to 0.78 in the magnetic strength of 640 G. For ω⩾7rpm, there is no significant influence of ω on ke. With ω⩽3rpm, ke is almost unity. The experimental results are compared with theory.