DEVELOPING WATER FOR CASEIN-DICHROMATE PHOTORESIST FILM AND PREPARATION OF THIS DEVELOPING WATER

摘要

PURPOSE:To obtain the developing water adequately adjusted in hardness without impairing the etching resistance and resolution of a resist film at the time of developing the photoresist film of a casein-dichromate system. CONSTITUTION:The hardness of the developing water is adjusted to >=10mg/1 and <=250mg/1 in terms of CaCO3 quantity, the chlorine ion concn. to <=420mg/1, the nitric acid ion concn. to <=4.5mg/1, the sulfuric acid ion concn. to <=40mg/1, the pH value to a 4 to 8 range, respectively. The hardness adjustment of the developing water is executed by mixing the developing water with slaked lime and carbon dioxide raw water and adjusting the inflow rate of the carbon dioxide into the raw water in such a manner that the pH value of the treated water enters the 4 to 8 range.