Negative-type resist sensitive to ionizing radiation.

摘要

The use of an acetalized polyvinyl alcohol having a molecular weight of 10,000 to 1,000,000 represented by the formula: <CHEM> wherein: R min represents a residue of an aldehyde or a ketone; H<2> represents a hydrogen atom, which may partially be substituted with an acetyl group; R<3> represents naught or a monomeric unit copolymerizable with vinyl acetate; and 1, m, n are integers indicating polymerization degrees, as a negative-type resist in ionizing radiation lithography.