Semiconductor cleaning liquid and method for producing semiconductor cleaning liquid

Abstract

The present invention provides a semiconductor cleaning liquid which contains isopropyl alcohol, while having a mass ratio of t-butyl alcohol of 1 ppm or less relative to the isopropyl alcohol. The present invention also provides a method for producing a semiconductor cleaning liquid, the method comprising a first distillation step in which a crude aqueous isopropyl alcohol solution that contains t-butyl alcohol as an impurity is supplied to a starting material supply plate of a first distillation column, and a first liquid distillate which contains a low boiling point impurity that has a lower boiling point than isopropyl alcohol is extracted from the column top of the first distillation column, while extracting a first bottom liquid from the column bottom of the first distillation column. In the first distillation step, a fluid containing water is supplied, from the outside of the first distillation column, to a predetermined plate that is above the starting material supply plate by two or more theoretical plates so that the water content in the liquid phase is 15% by mass or more at three or more theoretical plates among the plates of the first distillation column from the starting material supply plate to the column top.

Dependencies are inferred from the claim text.