Mk,
   Piranha question.  A simple not totally true explanation.  H2SO4 and
water have an exothermic reaction.  Care has to be taken not to mix the
2 too rapidly in case they explode.  If you consider H2O2 is really
water with an extra Oxygen atom you see where the exothermic reaction
comes from.  When this reaction takes place you are liberating Oxygen so
you have a great, hot, source of oxygen.  This oxides anything
particularly any organics.  Photo resist is a pure organic.  Think of an
Oxygen plasma stripper, we are producing a hot Oxygen ion that is mixed
with hot Oxygen and the gas mixture eats organics.  Bill Moffat