Materials are described suitable for optical lithography in the
ultraviolet region (including 157 nm and extreme ultraviolet region), and
for electron beam lithography. These materials are based on new
homopolymers and copolymers, they are characterized by the presence of
polyhedral oligomeric silsequioxanes in their molecule, and they are
suitable for single as well as bilayer lithography. Ethyl, or similar or
smaller size, groups are used as alkyl substituents of the silsequioxanes
in order to reduce problems related to pattern transfer, roughness, and
high absorbance at 157 nm (such problems occur when the substituents are
large alkyl groups such as cyclopentyl groups).