Positive resist for high energy radiation

摘要

A film of poly(methacrylamide) is heated to partially form imide bonds with elimination of ammonia, and such imide bonding causes crosslinking in the polymer to form a crosslinked polymer film. This film can be advantageously adapted as a positive resist capable of forming a positive image by exposure to radiation such as electron beams. The minimum incident charge required for such exposure is of the order of 10-7 coulomb/cm2, which is far lower than the level required in the use of conventional resists. The resist provided according to this invention is also capable of forming an excellent heat-resistant positive resist image by short-time exposure to radiation.