Patent ID: 7276323

Claim:
A negative working photoresist comprising: (a) a fluorine-containing polymer comprising a repeat unit derived from at least one ethylenically unsaturated compound characterized in that at least one ethylenically unsaturated compound is polycyclic and is selected from the group of structures H, I, J, and N wherein each of m and n is 0, 1 or 2, p is an integer of at least 3; a and b are independently 1 to 3 except that a is not=1 when b=2 or vice versa; R 1 to R 14 are the same or different and each represents a hydrogen atom, a halogen atom, a carboxyl group, a C 1 to C 14 secondary or tertiary alkyl carboxylate, a hydrocarbon group or a substituted hydrocarbon group; R 16 to R 21 are each independently hydrogen atoms, C 1 to C 12 alkyls, (CH 2 ) q CO 2 A, CO 2 (CH 2 ) q CO 2 A or CO 2 A wherein q is 1 to 12 and A is hydrogen or an acid protecting group with the proviso that at least one of R 18 to R 21 is CO 2 A, and at least one ethylenically unsaturated compound contains at least one fluorine atom covalently attached to an ethylenically unsaturated carbon atom; (b) at least one photoactive component, and (c) a cross-linking agent; wherein the fluorine-containing polymer does not contain aromatic functionality but contains sufficient functionality to render the photoresist developable so as to produce a relief image, upon imagewise exposure to ultraviolet radiation having a wavelength of <365 nm.