Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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Laser micromachining of high-aspect-ratio metallic channels for the application to microthermal devices

마이크로 열소자 제작을 위한 고세장비 금속채널의 레이저 가공

  • Oh, Kwang-Hwan (Department of Mechatronics, Gwangju Institute of Science and Technology) ;
  • Lee, Min-Kyu (Department of Mechatronics, Gwangju Institute of Science and Technology) ;
  • Jeong, Sung-Ho (Department of Mechatronics, Gwangju Institute of Science and Technology)
  • 오광환 (광주과학기술원 기전공학과) ;
  • 이민규 (광주과학기술원 기전공학과) ;
  • 정성호 (광주과학기술원 기전공학과)
  • Published : 2006.10.25
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Abstract

A fabrication method fur high-aspect-ratio microchannels in stainless steel using laser-assisted thermochemical wet etching is reported in this paper. The fabrication of deep microchannels with an aspect ratio over ten is realized by applying a multiple etching process with an optimization of process conditions. The cross-sectional profile of the microchannels can be adjusted between rectangular and triangular shapes by properly controlling laser power and etchant concentration. Excellent dimensional uniformity is achieved among the channels with little heat-affected area. Microchannels with a width ranging from 15 to $50{\mu}m$ can be fabricated with an aspect ratio of ten and a pitch of 150 m or smaller. The effects of process variables such as laser power, scan speed, and etchant concentration on the fabrication results, including etch width, depth, and cross-sectional profile are closely examined.

본 연구에서는 레이저유도 에칭기술을 이용한 스테인레스강의 고세장비 미세채널 제조에 대하여 기술한다. 공정 변수 최적화와 반복에칭을 통하여 높은 세장비를 갖는 미세채널을 제조하였으며 제조된 미세채널은 레이저출력과 에칭용액의 농도를 적절하게 조절함으로써 U 형상과 V 형상 사이의 단면 구조를 가지며 열변형이 없는 우수한 표면 형상을 보였다. 채널과 채널 사이의 간격은 $150{\mu}m$ 또는 그 이하이며 $15{\sim}50{\mu}m$ 범위의 폭을 갖는 10 이상의 고세장비 미세채널이 제조되었다. 레이저출력, 레이저초점의 이송속도, 에칭용액의 농도 등의 공정 변수들이 제조된 채널의 폭, 깊이 그리고 단면 형상에 미치는 영향에 대하여 자세히 보고한다.

Keywords

References

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