飛秒雷射之材料改質機制與應用研究

Abstract

在材料表面或内部製作出功能性微奈米結構，一直是熱門的研究議題。目前製造技術主要有蝕 刻製程、超精密加工、長脈衝雷射加工等方式。雷射製程具乾式及節省化學藥劑使用等綠色製程優 點，已逐漸應用在精密機械元件或醫材之製造。目前雖已有雷射積層製造技術可製作多孔性孔洞結 構，受限於雷射熱影響區，最小可製作之尺度為數十微米以上。對於如何在多孔性結構，透過雷射 精微奈米加工再提升表面功能性特徵，為國際上尚無研究投入之方向。

有鑑於此，本計晝擬研發飛秒光纖雷射快速改質技術，將建立孔洞内之飛秒雷射誘發週期表面 結構(laser induced periodic surface structure, LIPSS)機制模型、雷射向量光路模組、雷射摻雜模組等技 術，預期可在不同深寬比孔洞内，透過雷射光路調控與材料作用機制建立，製作大小與物化性可控 LIPSS結構，並以光學模仁為驗證載具，進行模擬與實驗驗證。以實現高精度雷射加工與創新應用為 計晝目標，研發之雷射光路模組與加工技術，預期可應用於台灣相關之精密機械與精微模具等產業。

Functional micro/nano structures have played critical roles in different applications and it is a hot research topic in advanced manufacturing technology. Micro/nano structures have been fabricated by various methods such as photolithography, ultra-precision machining, and long-pulse laser machining, etc. A laser machining approach, that is usable for micro-scale material ablation with dry process, provides alternative methods for the processing of micromechanical components and medical devices. For example, although the laser additive manufacturing process has the capability of producing porous structures and can be potentially used in mechanical components and customized implants; however, due to the heat-affected zone during the laser melting process, the minimum feature size is tens of microns or more. Laser nano-structuring of porous metal parts to enhance functional surface characteristics has not previously been presented.

This project aims at developing a femtosecond fiber laser modification technology, which investigates on the technologies of femtosecond laser induced periodic surface structure (LIPSS) in cavity, laser vector beam optical module, and laser doping module. By utilizing the femtosecond laser material interaction model, fabrication of controllable dimension and chemical composition LIPSS structure inside the cavity can be achieved. In addition, micro/nano structures fabricated on optical mold insert is demonstrated. In this project, we will establish the high precision laser machining technologies and novel application to provide high-performance micromechanical components and precision micro molds solution on Taiwan's industries.