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9
Defects in Silicon Wafers
9.1 Introduction
Single-crystal silicon grown by both the Czochralski (CZ) process and the oat-zone
(FZ) process inherently contains many crystallographic imperfections popularly known
as microdefects or grown-in defects. Prior to the 1960s, crystals contained dislocations
induced by the thermomechanical stresses near the vicinity of the melt-crystal interface.
A major breakthrough by Dash [1] allowed crystal growth without the thermomechani-
cally induced dislocations, and this brought a revolution in growing single crystals of
silicon with minimum defects. However, even though the crystals are free of thermome