基于光场调制的纳秒激光图案化石墨烯研究

Patterning of graphene by light field modulated nanosecond laser

激光加工技术在石墨烯制备领域得到了许多应用。目前激光图案化石墨烯的方法多为激光逐点扫描,而单次辐照实现图案化加工的方法鲜有报道。通过间光调制器改变激光的光场,使光束聚焦成图案,单次辐照直接在石墨烯样品上烧蚀实现图案化。控制激光能量为合适的值时可将石墨烯清晰地图案化而不损伤硅基底。通过拉曼光谱扫描成像发现石墨烯加工边缘清晰,精度达到μm量级,具有加工速度快、无需移动样品等特点。

Laser-based approaches for graphene synthesis,reduction,modification,cutting and micro-patterning have been developed and applied to the fabrication of various electronic devices.General method utilized in direct laser writing and patterning of graphene was realized by controlling the movement of the sample or the laser reflecting mirror,while patterning by single shot laser is rarely reported.In the present study,a single shot laser patterning graphene method via light field modulating is proposed.Via controlling the light field by special light modulator(SLM),nanosecond laser pulses focused by objective lens were modulated to the desired pattern.The4layer graphene in the laser irradiate region was damaged when laser energy was lager than0.03mJ.When the laser energy reached0.06mJ,clear pattern formed in graphene while no damage occurred in silicon base.The characteristics of graphene patterns were measured using Raman spectra imaging technology.The experimental results revealed that the light field modulated nanosecond laser remains potentially advantageous in graphene micro pattern processing with no need of moving the sample,quick processing and micrometer precision.