Investigation of flow pattern defects in as-grown and rapid thermal annealed CZSi wafers

Abstract

The flow pattern defects (FPDs) in as-grown and rapid thermal annealed 〈1 0 0〉 boron-doped CZSi wafers were investigated in this paper. The experimental results showed that a hole occurred on the apex of FPDs observed by atomic force microscope. The changes in the number and the size of the FPDs in as-grown and annealed wafers were measured by optical microscope after etching in Secco etchant. The size of FPDs became smaller, the density of FPDs reduced above 1100°C annealing and became very low above 1200°C annealing in an Ar atmosphere; the hole on the apex became shallower and larger. This mechanism was discussed.