In order to increase photosensitivity of PMMA as a deep UV photoresist, PMMA-based terpolymer, p(MMA-co-BOXM-co-TBMA), containing butanedione monoxime methacrylate(BOXM) as a photodegradable funtional group and t-butylbenzoyloxyethyl methacrylate(TBMA) as a light absorbing group was synthesized and its photosensitivity was compared with that of a copolymer, P(MMA-co-BOXM) containing t-butylbenzoic acid as an external photosensitizer. The relative photosensitivities of both polymers were studied by UV, IR analysis and viscosity measurements. The results of photodegradation study show that the terpolymer was more sensitive than the copolymer containing t-butylbenzoic acid and its photosensitivity increased with increasing BOXM content. The photosensitivity of the terpolymer cannot be increased by increase of TBMA content and the terpolymer composition with MMA:BOXM:TBMA=80:7:13 by molar ratio was found to be the most sensitive in photodegradation. The reason that the terpolymer was more sensitive than copolymer containing t-butylbenzoic acid was explained by internal energy transfer mechanism.

원자외선 포토레지스트로서 polymethyl methacrylate(PMMA)의 감광성을 증가시키기 위하여 고분자의 주쇄에 광분해기를 가진 단량체인 butanedione monoxime methacrylate(BOXM) 및 광증감기를 가진 단량체인 t-butylbenzoyloxyethyl methacrylate(TBMA)와 MMA의 삼원공중합체 P(MMA-co-BOXM-co-TBMA), (PMBT)를 합성하고 광분해 반응을 비교하였다. PMBT는 P(MMA-co-BOXM) 공중합체에 광증감제로서 t-butylbenzoic acid를 첨가하였을 경우보다 광분해가 잘 일어나 PMMA의 감광성을 증가시킬 수 있었으며 PMBT에 광분해기인 BOXM의 함량이 많으면 많을수록 광분해가 잘 일어났다. 광증감기인 TBMA기는 일정한 함량 이상에서는 광분해를 더 이상 증진시키지 못하였으며 가장 광분해가 잘 일어나는 PMBT의 조성비는 MMA:BOXM:TBMA=80:7:13 (몰비)인 경우였다. 이와같이 삼원공중합체의 광분해가 공중합체에 광개시제를 첨가하였을 경우 보다 광분해가 잘 일어나는 이유를 분자내 에너지전달 메카니즘으로 설명하였다.

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