UNDERLAYER FILM MATERIAL AND PATTERN FORMING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a resist underlayer film material that can be stripped with alkaline water without damaging an ion-implanted Si substrate or SiOsubstrate due to novolak resin having a recurring unit derived from fluorescein being hydrolyzed in alkaline water to generate a carboxyl group and turning soluble with an alkaline aqueous solution.SOLUTION: The present invention provides a photoresist underlayer film material to be used for lithography which comprises a novolak resin having a recurring unit derived from a substituted or unsubstituted fluorescein.