A basic developer/quencher solution formulated to include at least one supercritical fluid or liquid solvent and a base may be used to quench a photo-generated acid within a photoresist as well as develop the photoresist. The supercritical fluid or liquid solvent may be carbon dioxide and the base may be quaternary ammonium salt that has side groups that increase the solubility of the quaternary ammonium salt in carbon dioxide.