Chemically amplified positive resist for the next generation photomask fabrication

We have been developing novolak-based chemically amplified positive resists for the next generation photomask fabrication. In this paper, we report two different types of EB resists : RE-5150P and RE-5160P. Ow resist materials consist of four components : a novolak matrix resin, a polyphenol compound, an acid generator and a dissolution inhibitor. We applied two different types of dissolution inhibitors to our resist materials. RE-5150P and RE-5160P employed respective a high and a low activation energy type of a dissolution inhibitor. RE-5150P has high contrast and RE-5160P has wide process window. As a result, we confirmed RE-5150P could achieve 0.24 mu m line-and-space vertical resist pattern profiles at 8 mu C/cm(2) using the 50kV EB-writer HL800M, and RE-5160P has wide process window : post exposure delay stability is over 24hrs. and post coating delay stability is over 30days.