A phenol novolak resin has a peak intensity ratio of ortho-ortho bond (o-o)/ortho-para bond (o-p)/para-para bond (p-p) in a resin structure not substantially varying in each molecular weight fraction and has a weight average molecular weight (Mw) of 3000 to 20000 in terms of polystyrene, which peak intensity ratio is detected by
13
C-NMR analysis. The phenol novolak resin can form both dense pattern and isolation pattern with good shapes in the formation of a fine resist pattern of not more than 0.35 &mgr;m and has satisfactory sensitivity, definition, and focal depth range properties, and has a resin composition being uniform in each molecular weight fraction. A process for producing the phenol novolak resin, and a positive photoresist composition using the resin are also provided.
苯酚酚醛
树脂在
树脂结构中的正交-正交键(o-o)/正交-副交键(o-p)/副交键(p-p)的峰强度比在每个分子量组分中没有实质性变化,以聚
苯乙烯计,其重量平均分子量(Mw)为 3000 至 20000,该峰强度比通过以下方法检测
13
C-NMR 分析可检测到这一峰值强度比。
苯酚酚醛
树脂可以形成致密图案和隔离图案,在形成不超过 0.35 &mgr;m 的精细抗蚀剂图案时具有良好的形状,并具有令人满意的灵敏度、清晰度和焦深范围特性,而且每个分子量分数的
树脂成分都是均匀的。此外,还提供了生产
苯酚酚醛
树脂的工艺和使用该
树脂的正性光刻胶组合物。