Reducing or eliminating watermark-type defects during semiconductor device fabrication are described and can comprise treating photoresist using one of several embodiments. In some embodiments, the propensity for defect formation is reduced/eliminated by conditioning the photoresist surface through the application and removal of a sacrificial overcoat. In other embodiments, existing defects are reduced/eliminated by exposing the photoresist surface to a defect-stripping material during post-develop processing.