한국광학회지 (Korean Journal of Optics and Photonics)

  • 제14권3호
  • /
  • Pages.312-320
  • /
  • 2003
  • /
  • 1225-6285(pISSN)
  • /
  • 2287-321X(eISSN)
한국광학회 (Optical Society of Korea)
권호 표지
DOI QR코드

DOI QR Code

355nm 파장의 DPSSL을 이용한 폴리머의 3차원 미세 형상 광가공기술

Three-dimensional micro photomachining of polymer using DPSSL (Diode Pumped Solid State Laser) with 355 nm wavelength

  • 장원석 (한국기계연구원 나노공정그룹) ;
  • 신보성 (한국기계연구원 나노공정그룹) ;
  • 김재구 (한국기계연구원 나노공정그룹) ;
  • 황경현 (한국기계연구원 나노공정그룹)
  • 발행 : 2003.06.01
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

본 연구에서는 355 nm의 파장을 갖는 Nd:YVO$_4$ 3고주파 DPSS 레이저를 이용하여 폴리머의 3차원 미세형상 가공기술을 개발하였다. UV레이저와 폴리머의 어블레이션에 관한 메커니즘을 설명하였으며 비교적 UV영역에서 파장이 긴 355 nm파장의 영역에서는 광열분해 반응으로 가공되고 이에 따른 폴리머의 광학적 특성을 살펴보았다. 광 흡수율 특성이 우수한 폴리머가 광가공 특성이 좋은 것으로 나타났으나 벤젠구조가 많이 포함되어 있는 폴리이미드의 경우는 광분해후 다시 새로운 화학적 결합이 이루어져 가공부 면이 좋지 않은 면을 보였다. 레이저의 다중 주사방식으로 가공하기위하여 표면의 오염이 적은 폴리카보네이트를 시편으로 사용하여 3차원 적으로 모델링한 직경 1 mm와 500 $\mu\textrm{m}$의 마이크로 팬을 가공하였다. 레이저 발진 효율이 높고 유지비가 적은 355 nm의 DPSSL을 이용한 3차원 가공기술의 개발로 향후 저비용으로 빠른 시간에 미세부품을 개발하는 기술에 기여할 것으로 예상된다.

The basic mechanistic aspects of the interaction and practical considerations related to polymer ablation were briefly reviewed. Photochemical and photothermal effects, which highly depend on laser wavelength have close correlation with each other. In this study, multi-scanning laser ablation processing of polymer with a DPSS (Diode Pumped Solid State) 3rd harmonic Nd:YVO$_4$ laser (355 nm) was developed to fabricate a three-dimensional micro shape. Polymer fabrication using DPSSL has some advantages compared with the conventional polymer ablation process using KrF and ArF laser with 248 nm and 193 nm wavelength. These advantages include pumping efficiency and low maintenance cost. And this method also makes it possible to fabricate 2D patterns or 3D shapes rapidly and cheaply because CAD/CAM software and precision stages are used without complex projection mask techniques. Photomachinability of polymer is highly influenced by laser wavelength and by the polymer's own chemical structure. So the optical characteristics of polymers for a 355 nm laser source is investigated experimentally and theoretically. The photophysical and photochemical parameters such as laser fluence, focusing position, and ambient gas were considered to reduce the plume effect which re-deposits debris on the surface of substrate. These phenomena affect the surface roughness and even induce delamination around the ablation site. Thus, the process parameters were tuned to optimize for gaining precision surface shape and quality. This maskless direct photomachining technology using DPSSL could be expected to manufacture tile prototype of micro devices and molds for the laser-LIGA process.

키워드

참고문헌

  1. Appl. Phys. Lett. v.41 no.6 Self-developing photoetching of poly(ethylene terephthalate) films by far-ultra-violet excimer laser radiation R.Srinivasan;V.Mayne-Banton https://doi.org/10.1063/1.93601
  2. J. Am. Chem. Soc. v.104 Ablative photodecomposition: action of far-ultraviolet(193 nm) laser radiation on poly(ethylene terephthalate) films R.Srinivasan;W.J.Leigh https://doi.org/10.1021/ja00388a052
  3. J. Appl. Phys. v.58 no.5 Excimer laser etching of polyimide J.H.Brannon;J.L. Lankard;A.I. Baise;F.Burns;J.Kaufman https://doi.org/10.1063/1.336012
  4. J. Vac. Sci. Technol. A v.4 no.3 Laser ablation of polymers J.T.C. Yeh https://doi.org/10.1116/1.573823
  5. Laser Chem v.10 Ultraviolet laser photoablation of polymers: a review and recsults S.Lazare;V.Grainier https://doi.org/10.1155/1989/18750
  6. Proc. SPIE HPLA Ⅳ v.4760 Polymers designed for laser applications: fundamentals and applications T.Lippert;M.Hauer;C.R.Phipps;A.J. Wlkaun https://doi.org/10.1117/12.482044
  7. Appl. Phys. A v.63 no.2 Femtosecond, picosecond and nano-second laser ablation of solids B.N.Chichkov;C.Momma;S.Nolte;F.von-Alvensleben;A.Tuennermann https://doi.org/10.1007/BF01567637
  8. Appl. Surf. Sci. v.109-110 Laser-solid interaction in the femtosecond time regime D.von der Linde;D.Sokolowski-Tinten;K.Bialkowski https://doi.org/10.1016/S0169-4332(96)00611-3
  9. Nature v.412 Finer features for functional microdevices S.Kawata;H.Sun;T.Tanaka;K.Takada https://doi.org/10.1038/35089130
  10. Proc. SPIE v.3898 New developments and applications in the production of 3D micro-structures by laser micro machining N.H.Rizvi;P.T. Rumsby;M.C. Gower https://doi.org/10.1117/12.368513
  11. Proc. SPIE v.4760 New techniques for laser micromachining MEMS devices C.Abbott;R.Allott;B.Bann;K.Boehlen;M.Gower;P.Rumsby;I.S.Boehlen;N.Sykes https://doi.org/10.1117/12.482096
  12. J. Appl. Phys. v.60 Dynamics of UV laser ablation of organic polymer surface E.Sutcliffe;R.Srinivasan https://doi.org/10.1063/1.337698
  13. J. Appl. Phys. v.73 Ablation of polymethyl methacrylate films by pulsed (ns) ultraviolet and infrared (9.17 ㎛) lasers: A comparative study by ultrafast imaging E.Srinivasan https://doi.org/10.1063/1.353048
  14. Appl. Phys. A v.56 Threshold behavior in polyimide photoablation: single-shot rate measurements and surface-temperature modeling S.Kuper;J.Brannon;K.Brannon https://doi.org/10.1007/BF00351902
  15. Laser ablation of polymers, in photochemical processing of electronic materials P.E.Dyer;I.W. Boyd(ed.);R.B. Jackman(ed.)
  16. Proc. SPIE v.774 Photo-etching of polymers with Excimer laser Y.S.Liu;H.S. Cole;H.R. Philipp;R.Guida https://doi.org/10.1117/12.940398
  17. J. Opt. Soc. Korea v.2 Intracavity frequency doubling of a slab Nd:YAG laser pumped by high power diode laser array J.Lee;H.J.Moon;J.Yi https://doi.org/10.3807/JOSK.1998.2.1.005
  18. 한국광학회 동계학술대회논문집 폴리머와 UV레이저의 열적, 광화학적 반응특성을 고려한 직접식 마이크로 3차원 광가공기술 장원석;신보성;김재구;황경현
  19. 한국레이저가공학회 추계학술대회논문집 DPSSL을 이용한 3차원 마이크로 형상 조각기술 장원석;신보성;김재구;황경현
  20. Appl. Phys. A v.63 Comparison of the transmission behavior of a triazeno-polymer with a theoretical model T.Lippert;L.S.Bennett;T.Nakamura;H.Niino;A.Ouchi;A.Yabe https://doi.org/10.1007/BF01567878