A method for reducing the metal ion content of aminoaromatic chromophores and using it for the synthesis of bottom antireflective coatings for low photoresist metals.

摘要

PURPOSE: Described are a process for producing bottom anti-reflective coating compositions having a very low level of metal ions utilizing specially treated anion exchange resins, and also a method for producing semiconductor devices by producing photoimages on a substrate using such bottom anti-reflective coating compositions. CONSTITUTION: The formation process of bottom anti-reflective coating composition comprises the steps of making a solution of an aminoaromatic chromophore in an electronic grade casting solvent; adding an electronic grade polar solvent to make a homogenous solution; reacting the low metal solution and a polymer with an anhydride group at a temperature between about 120 to 160C for about 6-8 hours; and adding deionized water to the reaction product, stirring for about 30-90 minutes, decanting the water layer, distilling to remove residual water and thereby producing a bottom anti-reflective coating composition having levels of sodium and iron ions less than 100 ppb each.