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


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.


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