Developing solution for positive-working photoresist comprising a metal ion free organic base and an anionic surfactant

A developing solution for positive-working photoresist compositions which comprises:

• (a) an aqueous medium;
• (b) an organic basic compound free from metal ions in an an amount sufficient to obtain a pH between 11.0 and 13.5;
• and
• (c) a fluorine-containing surface active agent in a concentration in the range from of 50 to 5000 ppm by weight, based on the amount of the developing solution, said fluorine-containing surface active agent being selected from the group consisting of an ionic fluorine-containing compounds represented by the general formula R.sub.f COOM and R'.sub.f SO.sub.3 M, wherein R.sub.f and R'.sub.f are each a monovalent hydrocarbon group having from 2 to 20 carbon atoms, of which at least a part of the hydrogen atoms are replaced with fluorine atoms, and M is an atom or group selected from the group consisting of hydrogen, ammonium, quaternary ammonium of the formula NR.sub.4, wherein each R is independently hydrogen or an alkyl group having 1 to 3 carbon atoms.