Study of Metals by Femtosecond Laser Processing for Electro-Optics Applications

Abstract:

Femtosecond laser (FS-laser) microstructuring of metals has become a promising tool because of its non-contact nature, which allows the micromachining and direct processing of materials with a minimized volume of heat-affected zone for electro-optics applications such as light emitting diodes (LED) and solar photovoltaic (PV) lighting. This study presents ultra-short pulse (10^-15 sec) FS-laser processing. Through integrating the laser source, optical system and dynamic control modules, the materials of metals with micro-scale or nanoscale structures can be fabricated. In traditional processing such as semiconductor processing, development, exposure and etching necessitate expensive equipment and time-consuming tasks. With FS-laser processing, high-precision patterns are obtained, which will be a great benefit to keeping costs down. In this study, the wavelengths of FS-laser ablation are employed using visible and infrared light. To make a breakthrough in electro-optics processes, the CIGS thin-film of solar cells in metal process can be easily produced by the FS-laser. The ablation speed of the FS-laser for thin film layer CIGS solar cells can reach 2000 mm/s which is faster than the current Nd:YAG laser machine (~1000 mm/s). On the other hand, the minimum size of metal lines can be controlled to a value that is lower than 40 µm. Furthermore, green energy can be effectively developed for the future.

• Periodical: Key Engineering Materials (Volume 516)
• Pages: 263-268
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.516.263
• Online since: June 2012
• Authors: Cho Wei Chang, Tien Li Chang, Ting Kai Tsai, Chia Jen Ting, Chien Ping Wang, Chang Pin Chou
• Keywords: CIGS Thin-Film, Electronics, Electro-Optics, Femtosecond Laser, Metal, Solar Cell

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