A fine feature formation method and apparatus provide photon induced deposition, etch and thermal or photon based treatment in an area of less than the diameter or cross section of a STED depleted laser beam. At least two STED depleted beams are directed to a reaction location on a substrate where a beam overlap region having an area smaller than the excitation portion of the beams is formed. A reactant or reactants introduced to the reaction region is excited by the combined energy of the excitation portions of the two beams, but not excited outside of the overlap region of the two excitation portions of the beams. A reactant is caused to occur only in the overlap region. The overlap region may be less that 20 nm wide, and less than 1 nm in width, to enable the formation of substrate features, or the change in the substrate, in a small area.