Negative Resist Composition for Long-Term Storage Stability

The patent changes the chemical parameters of the acid generator by selecting specific compounds (triphenylsulfonium triflate, tosylate, or mesylate) with controlled decomposition characteristics. This parameter optimization ensures the acid generator remains stable during long-term storage but becomes sufficiently reactive under exposure conditions, resolving the contradiction between storage stability and functional duration.

The patent employs a composite resist composition containing multiple components: resin (A1) with specific functional groups, crosslinking agent (E), and optimized acid generator (B). This composite formulation creates synergistic effects where each component contributes to both storage stability and pattern formation capability, allowing the composition to maintain reliability throughout extended storage periods.

The patent optimizes the chemical parameters of the acid generator by selecting compounds with specific structural characteristics (triphenylsulfonium salts with triflate, tosylate, or mesylate anions). These parameters are tuned to achieve a balance: the generators remain stable during storage but decompose efficiently under exposure to generate sufficient acid for complete crosslinking, ensuring both storage stability and pattern formation quality.

The patent creates local quality differentiation within the resist system by using specific acid generators that exhibit stable properties during storage but become highly reactive under exposure conditions. This localized change in reactivity ensures that the acid generator maintains stability where needed (during storage) while providing the necessary reactivity where required (during pattern formation).