MODIFIED NOVOLAK PHENOLIC RESIN, MAKING METHOD, AND RESIST COMPOSITION

摘要

A modified novolak phenolic resin is obtained by reacting a novolak phenolic resin containing at least 50 wt % of p-cresol with a crosslinker. This method increases the molecular weight of the existing novolak phenolic resin containing at least 50 wt % of p-cresol to such a level that the resulting modified novolak phenolic resin has heat resistance enough for the photoresist application.

主权项

1. A method of preparing a modified novolak phenolic resin, comprising the steps of mixing (A) a novolak phenolic resin obtained from condensation of a phenol containing at least 50% by weight of p-cresol and an aldehyde, or (B) a mixture of (b-1) at least 50% by weight of a p-cresol novolak resin obtained from condensation of p-cresol and an aldehyde and (b-2) the balance of another novolak phenolic resin obtained from condensation of a phenol other than p-cresol and an aldehyde with a crosslinker, simultaneously or subsequently adding an acidic catalyst selected from the group consisting of oxalic acid, acetic acid, benzenesulfonic acid, p-toluenesulfonic acid, xylenesulfonic acid, p-phenolsulfonic acid, methanesulfonic acid, and ethanesulfonic acid thereto, and effecting reaction at a temperature of 10 to 80° C.