Patterns on the backside of silicon wafers coated with Si3N 4 films have been observed on their front surfaces after wet oxidation. This pattern transfer phenomenon is the result of a reduction in the oxidation rate of the front-surface nitride film over areas where the backside films have been removed. This reduction has been attributed to the influence of the stress in the nitride film on its oxidation rate. In areas where the backside nitride has been removed, localized sample bowing results in stress relief in the front-surface film and a lower oxidation rate of the nitride film.