Analysis of local lattice strain around oxygen precipitates in Czochralski-grown silicon wafers using convergent beam electron diffraction

The local lattice strain field around oxygen precipitates in Czochralski-gr own silicon (CZ-Si) wafers has been measured quantitatively using convergen t beam electron diffraction (CBED). As a result of the strain analysis from higher-order Lane zone patterns in the CBED disk, strain of the silicon la ttices was found in the vicinity of oxygen precipitates, i.e., platelet typ e and polyhedral type. The strain along the normal direction to the precipi tate is compressive, and the strain along the parallel direction to the pre cipitate is tensile. The lattice strain field around the precipitate decrea ses monotonically as a function of distance from the precipitate/matrix int erface. Further, the morphological change in the growth process of the prec ipitate is important for the formation of the local lattice strain.