PURPOSE: To obtain an accurate pattern by adhering metal particles on a chromium film formed with a resist of a desired pattern on a substrate, then supplying an acidic etching solution to the substrate to etch the part of the film, then removing the particles and etching the remainder.

CONSTITUTION: Metal particles are adhered on a chromium having no pattern by a metal particle supplying unit 12 in a metal particle supplying chamber 11, fed by a conveying belt 18 to an etching solution supplying tank 11, and an etching solution 5 is sprayed by a spray nozzle 14 on a substrate 1 having the chromium film formed with a resist pattern. As the snbstrate 1 is conveyed, chromium oxide is reduced by the particles 4 and the solution 5, the particles 4 are flown by the sprayed solution to drop on a metal particle recovery plate 16, the particles 4 on the film are removed, the chromium film is further etched to etch the film 2 in a desired shape. Thus, a fine pattern can be accurately formed at ambient temperature on the film on the substrate without producing hexavalent chromium.