Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Microlens Fabrication Method by the Modified LICA Process

변형된 LIGA 공정을 이용한 마이크로렌즈 제작방법

  • 이성근 (포항공과대학교 기계공학과) ;
  • 이광철 (포항공과대학교 대학원 기계공학과부) ;
  • 이승섭 (포항공과대학교 대학원 기계공학과부)
  • Published : 2002.11.01
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Abstract

Microlenses and microlens arrays are fabricated using a novel fabrication technology based on the exposure of a resist (usually PMMA) to deep X-rays and subsequent thermal treatment. The fabrication technology is very simple and produces microlenses and microlens arrays with good surface roughness (less than 1 nm). The molecular weight and glass transition temperature of PMMA is reduced when it is irradiated with deep X-rays. The microlenses is produced through the effects of volume change, surface tension, and reflow during thermal treatment of irradiated PMMA. The geometry of the microlens is determined by parameters such as the X-ray dose applied to the PMMA, the diameter of the microlens, along with the heating temperature, heating time, and cooling rate in the thermal treatment. Microlenses are produced with diameters ranging from 30 to 1500 ${\mu}{\textrm}{m}$. The modified LIGA process is used not only to construct hemispherical microlenses but also structures that are rectangular-shaped, star-shaped, etc.

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References

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