In a preferred method of forming a bilevel resist, a 0.6-1 .mu.m underlayer of a diazonaphthoquinone-containing photoactive compound in a novolac resin matrix is coated on a substrate by spin-applying.
Generally, during exposure in a non-chemically amplified system, absorption of 1 photon by the photoactive compound generates 1 molecule of a carboxylic acid.
Moreover, when these polymers are combined with diazonaphthoquinone-based photoactive compounds (PACs), exposure doses of >100 mJ/cm@2 at 365 nm are required to pattern the resist.
さらに、ジアゾナフトキノンを主成分とする光活性化合物(PAC)と結合されるときには、レジスタをパターン化するのに100mJ/cm2 以上の露光線量を必要とする。