Chemical consolidation of photoresists in the UV range
View Patent ↗Structured resists are consolidated, that is post-exposure amplified. The amplifying agent used is a compound which contains at least one bicyclic or polycyclic group. The amplifying agent is attached via a reactive group to a reactive anchor group of a polymer that is used for the resist. The process is particularly suitable for amplifying copolymers of cycloolefins and maleic anhydride.
1. A method of consolidating structured resists, which comprises:
providing a substrate with a photoresist comprising at least one polymer containing anchor groups for attachment of an amplifying agent;
sectionally exposing and developing the resist to form a structured resist;
applying a silicon-free amplifying agent producing an increase in the etch resistance of the resist to the structured resist,
the amplifying agent containing at least one bicyclic or polycyclic non-aromatic group and at least one reactive group capable of coordinating to the anchor groups of the polymer; and
removing excess amplifying agent.
2. The process according to claim 1 , wherein the photoresist is a chemically amplified photoresist and the method further comprises subjecting the structured resist to flood exposure prior to the step of applying the amplifying agent.
3. The process according to claim 1 , wherein the photoresist is a chemically amplified photoresist comprising a thermoacid generator and the method further comprises heating the structured resist to a temperature at which an acid is liberated from the thermoacid generator.
4. The process according to claim 1 , which comprises applying the amplifying agent as a solution to the structured resist.
5. The process according to claim 4 , which comprises adding to the solution of the amplifying agent a swelling promoter for swelling the structured resist.
6. The process according to claim 1 , wherein the amplifying agent contains at least two reactive groups.
7. The process according to claim 1 , wherein the reactive group of the amplifying agent is a basic group.
8. The process according to claim 1 , wherein the amplifying agent is an amplifying agent selected from the group consisting of
bis(aminomethyl)adamantane, bis(aminoethyl)adamantane,
bis(aminopropyl)adamantane, norbornyldiamine,
bis(aminomethyl)norbornane, bis(aminoethyl)norbornane,
bis(aminopropyl)norbornane,
bis (aminomethyl)bicyclo [2.2.2]octane,
bis(aminoethyl)bicyclo[2.2.2]octane,
bis(aminopropyl)bicyclo[2.2.2]octane,
bis(aminomethyl)tricyclo[5.2.1.0 2,6 ] decane,
bis(aminoethyl)tricyclo[5.2 1.0 2,6 ] decane, and
bis(aminopropyl)tricyclo[5.2.1.0 2,6 ] decane.
9. The process according to claim 1 , wherein the polymer comprises repeating units containing groups selected from the group consisting of carboxylic acid anhydride groups and bicyclic or polycyclic non-aromatic groups.