雷射直寫系統製作繞射光學元件之研究

Research of the Diffractive Optical Elements by using of Laser Direct Writing System

黃建中(Jian-Jhong Huang)

指導教授 ： 徐力弘

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2012年)

摘要

本文以共軛焦的概念架設雷射直寫系統，採用光學讀取頭作為光源，雷射光束經物鏡聚焦後垂直照射在光阻劑SU-8上，藉由控制雷射光的功率與時間來調整曝光參數，此方法不必使用光罩，可節省光罩設計與製作的時間，在多重曝光時避免了對準的問題。由於系統具有共軛焦檢測的能力，在曝光時可即時檢測光阻的位置，達成製作繞射元件之目的。
本系統在曝光前使用紅光雷射測量光阻厚度，再以藍光雷射及壓電平台PZT進行寫入的動作。寫入的功率密度為3.88μJ/μm2，可成功製作出節距3μm，線寬1.68μm的繞射光柵。

關鍵字

雷射直寫 ； 光阻劑SU-8 ； 繞射元件

並列摘要

This study use the concept of confocal microscope to set up laser direct writing system. We use laser of the optical pickup head as the light source. Through the objective lens, laser beam will focus vertically on the SU-8 photoresist. To find the appropriate exposure parameters, we adjust the power and the exposure time of laser beam. In this way, it is unnecessary using optical mask, so we don’t require to design and produce the mask. Besides, we can avoid the problems caused by multiple-exposure alignment. This system with confocal detection can measure the position of photoresist instantly in exposure to achieve the goal of manufacturing diffractive elements.
This system uses red laser to measure the thickness of photoresist, and then uses blue laser and PZT to exposure (the power density is 3.88μJ/μm2). And it can produce grating whose pitch is 3μm and line width is 1.68μm.

並列關鍵字

Laser direct writing ； SU-8 photoresist ； Diffractive elements

參考文獻

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