초록

One of display trends today is development of high pixel density. To get high PPI, a small size of pixel mustbe developed. RGB pixel is arranged by evaporation process which determines pixel size. Normally, a fine metal mask(FMM; Invar alloy) has been used for evaporation process and it has advantages such as good strength, and low thermalexpansion coefficient at low temperature. A FMM has been manufactured by chemical etching which has limitation tocontrolling the pattern shape and size. One of alternative method for patterning FMM is laser micromachining. Femtosecond laser is normally considered to improve those disadvantages for laser micromachining process due to suchshort pulse duration. In this paper, a femtosecond laser drilling for thickness of 16 FMM is examined. Additionally,we introduce experimental results for controlling taper angle of hole by vibration module adapted in laser system. Weused Ti:Sapphire based femtosecond laser with attenuating optics, co-axial illumination, vision system, 3-axis linear stageand vibration module. By controlling vibration amplitude, entrance and exit diameters are controllable. Using vibratingobjective lens, we can control taper angle when femtosecond laser hole drilling by moving focusing point. The largeramplitude of vibration we control, the smaller taper angle will be carried out.

키워드

Femtosecond laser machining, AMOLED display, Invar, Vibration, Processing control

참고문헌(5)open

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