METHOD AND DEVICE FOR CLEANING PHASE SHIFT PHOTOMASK

摘要

PROBLEM TO BE SOLVED: To provide a method for cleaning a photomask which exhibits a profound effect to remove residual sulfuric acid and foreign materials, and is capable of effectively removing foreign materials without giving a variation to the transmissivity, etc. of the light shielding film (MoSiON film) of the phase shift photomask.;SOLUTION: The photomask cleaning method comprises a first process for degrading organic matters present on the surface of a photomask used as a master disk in a photoengraving process of semiconductor manufacturing, and for cleaning the photomask using a high-temperature mixture of sulfuric acid and hydrogen peroxide solution for removing metal impurities, a second process for removing the residual sulfuric acid on the surface of the photomask, a third process for removing foreign matters adhered to the surface of the photomask, and a fourth process for drying the photomask after the first, second, and third processes. In the second process, the residual sulfuric acid on the surface of the photomask is removed with the use of anode water. In the third process, the foreign matters are removed with the use of cathode water.;COPYRIGHT: (C)2006,JPO&NCIPI