Hristovski Ilija R, Herman Luke A, Mitchell Michael E, Lesack Nikolai I, Reich Jason, Holzman Jonathan F
Integrated Optics Laboratory, School of Engineering, University of British Columbia, Kelowna, BC V1V 1V7, Canada.
Nanomaterials (Basel). 2022 Apr 7;12(8):1241. doi: 10.3390/nano12081241.
In this work, we put forward a rigorous study on ultraviolet (355-nm) laser irradiation of polyimide for the realization of high-quality laser-induced graphene (LIG) with micron-scale features. High-quality material and micron-scale features are desirable-but often at odds-given that small features demand tightly focused beam spots, with a predisposition to ablation. As such, we investigate the synthesis of LIG by correlating the material characteristics, as gleaned from scanning electron microscopy and Raman spectroscopy, to the incident optical fluence, as a measure of applied optical energy per unit area. The study reveals that high-quality LIG, with ratios of Raman 2D-to-G peak heights approaching 0.7, can be synthesized with micron-scale features, down to 18 ± 2 μm, given suitable attention to the optical fluence. Optimal characteristics are seen at optical fluences between 40 and 50 J/cm, which promote graphenization and minimize ablation. It is hoped that these findings will lay a foundation for the application of LIG in future integrated technologies.
在这项工作中，我们对聚酰亚胺进行紫外（355纳米）激光辐照展开了严谨研究，以实现具有微米级特征的高质量激光诱导石墨烯（LIG）。鉴于小尺寸特征需要紧密聚焦的光斑，这往往会导致烧蚀，所以高质量材料和微米级特征虽令人期待，但通常相互矛盾。因此，我们通过将扫描电子显微镜和拉曼光谱所获取的材料特性与入射光通量（作为单位面积施加光能量的度量）相关联，来研究LIG的合成。研究表明，在适当关注光通量的情况下，拉曼2D峰与G峰高度比接近0.7的高质量LIG能够以低至18±2μm的微米级特征合成。在40至50 J/cm²的光通量下可观察到最佳特性，该光通量能促进石墨化并使烧蚀最小化。希望这些发现将为LIG在未来集成技术中的应用奠定基础。
