Heavily boron-doped Czochralski (CZ) silicon crystal growth: segregation and constitutional supercooling

Abstract

Heavily boron-doped silicon single crystals have been grown successfully by the Czochralski (CZ) method. The limit of boron concentration for silicon single crystal growth, the reason for polycrystallization, and boron segregation with heavy boron doping have been investigated. It is found that a silicon single crystal can be obtained even when the boron concentration in the silicon crystal is up to about 2.8×10 20 atoms cm −3. In the heavily boron-doped silicon crystal growth, the reason for polycrystallization is the constitutional supercooling. It is confirmed that the equilibrium segregation coefficient of boron decreases from 0.8 with increasing boron concentration in the silicon melt, and it affects the occurrence of the constitutional supercooling.