Abstract: In an example, a method of manufacturing a semiconductor device includes providing a semiconductor substrate comprising an unpolished CZ silicon substrate, a substrate upper side, and a substrate lower side opposite to the substrate upper side. The method includes first annealing the semiconductor substrate at a first temperature in an inert environment for a first time. The method includes second annealing the semiconductor substrate at a second temperature in a wet oxidation environment for a second time. The first annealing dissolves inner wall oxide in bulk region voids and the second annealing fills the voids with semiconductor interstitials. In some examples, the CZ silicon substrate is provided from a CZ ingot grown in the presence of a magnetic field and using continuous counter-doping. The method provides, among other things, a CZ silicon substrate with reduced crystal originated particle (COP) defects, reduced oxygen concentration, and reduced radial resistivity variation.