| 摘要 |
PURPOSE:To remove the foreign matter sticking to a phase shift mask at the time of producing the mask and at the time of correcting shifter defects by etching the surface by the dissolving effect of the ammonium hydroxide and oxidizing power of hydrogen peroxide in a soln. CONSTITUTION:This phase shift mask 1 is formed with a conductive film 3 for preventing electrification in electron beam exposing on a glass substrate 2 and phase shifters 4 for controlling the phase of the light to be transmitted is arranged on this conductive film 3. Further, chromium layers 5 which are light shielding films are formed on the phase shifters 4. The substrate is then etched into an H2)-H2O2-NH4OH soln. of, for example, a volumetric ratio of 7:2:1, by which the surface of the phase shifters 4 and the surface of the conductive film 3 are etched. As a result, the surfaces of the phase shifters 4 and the conductive film 3 are etched by the dissolving effect of the ammonium hydroxide and oxidizing power of the hydrogen peroxide in the soln. Then, foreign matter 6 at the time of correcting the shifter defects is lifted off and removed from the phase shifters 1. |
