Process for forming anti-reflection coating and method for improving accuracy of overlay measurement and alignment

摘要

A method for forming an anti-reflection coating (ARC) with no hole over an overlay mark is described, which applies a fluid material of the ARC onto a substrate and then conducts at least two curing steps to convert the fluid material into the ARC. Such a bottom anti-reflection coating with no hole over the overlay mark can improve accuracy of the overlay measurement of lithography, thereby improving the alignment accuracy of the lithography process.