Patent ID: 7964275

Claim:
A silicon wafer, in the entire volume of which crystal lattice vacancies represent the prevalent point defect type, the silicon wafer having a region which is rotationally symmetric with respect to its axis and has a width of at least 80% of the radius of the silicon wafer, this region comprising agglomerates of crystal lattice vacancies with a size of at least 30 nm in a density of at most 6 10 3 cm −3 and agglomerates of crystal lattice vacancies with a size of from 10 nm to 30 nm in a density of from 1·10 5 cm −3 to 3·10 7 cm −3 , the silicon wafer comprising OSF seeds in a density of from 0 to 10 cm −2 and an average BMD density in its interior of from 5·10 4 cm −2 to 5·10 5 cm −2 , the BMD density varying at most by a factor of 10 in the radial direction over the entire radius of the silicon wafer, and wherein the silicon wafer comprises a BMD-free denuded zone layer at least on a front side of the silicon wafer, which is distinguished in that the first BMD on the entire front side of the silicon wafer is found at a depth of at least 5 μm and the first BMD is found on average at a depth of at least 8 μm.