High performance silicon wafer with wide grown-in void free zone and high density internal gettering site achieved via rapid crystal growth with nitrogen doping and high temperature hydrogen and/or argon annealing

摘要

Grwon-in voids annihilation phenomena due to high temperature hydrogen and argon annealing have been investigated for nitrogen doped Czochralski silicon substrate. Grown-in voids can be annihilated up to 2approx10 #mu#m depending on the initial oxygen concentration in nitrogen doped substrte, while they can still exist at 0approx2 #mu#m depth in non-nitrogen doped one. This annihilation efficiency strongly depends on the initial void size and oxygen concentration. The combination of rapid growth and nitrogen doping is the best to achieve smaller void so as to deeper void free zone. In addition, in the same growth rate crystal, the lower the initial oxygen concentration the deeper the void free zone. A model based on point defect injection and out-diffusion is proposed to explain the dependence of void annihilation depth on initial oxygen concentration and void size. The simulation results are quantitatively consistent with the experimental results. This is the first report which revealed the dependence of grown-in voids annihilation depth on oxygen concentration in nitrogen doped Czochralski silicon substrate.