Methods for carrying out lithography with a carbon dioxide development system are described. In some embodiments the methods involve preferential removal of a darkfield region; in other embodiments the methds involve preferential removal of a light field region. The carbon dioxide development systems include a quaternary ammonium salt, preferably a quaternary ammonium hydroxide, halide, or carbonate. Compositions for carrying out the methods are also described. The quaternary ammonium salts preferably contain at least one CO2-philic group, such as a siloxane-containing group or a fluorine-containing group.