In immersion lithography, to avoid internal reflections in the final element of the projection system, immersion fluid and topcoat, the thicknesses, d.sub.l, d.sub.tc and d.sub.r, and refractive indices, n.sub.l, n.sub.tc and n.sub.r, of the immersion fluid, topcoat and resist may meet the following criteria: n.sub.l.ltoreq.n.sub.tc.ltoreq.n.sub.r d.sub.l>.about.5..lamda. d.sub.tc.ltoreq..about.5..lamda.