Oxygen plasma treatment is often used to clean the surface or etch graphene for functional structures. Some unique properties such as photoluminescence (PL), energy bandgap engineering, and so on are presented in single-layer graphene (SLG). Compared with SLG, few-layer graphene (FLG) has higher luminescence intensity, slower decay rate, and better controllability. It is more universal in the application of new optoelectronic devices and transparent electrodes. So, a systematic study is provided to analyze the mechanism between chemical vapor deposition of few-layer graphene and oxygen plasma process based on the optical characterization method. Surface morphology, structural defects, resistance change, chemical state, and PL are traced and investigated under different oxygen plasma treatment times. The CO and CO bonds on the surface of the FLG appear to increase and then decrease with oxygen plasma etching based on X-ray photoelectron spectroscopy (XPS) characterization. A linear square resistance change is presented from 1.4 to 4.8 kΩ sq⁻¹. Besides that, an obvious redshift–blueshift change is produced in fluorescence characteristic spectra. Herein, comprehensive research on the influencing mechanism of graphene and oxygen treatment is exhibited, which provides the potential to construct optoelectronic devices.

中文翻译：

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氧等离子体处理的少层石墨烯的光学研究

氧等离子体处理通常用于清洁表面或蚀刻功能结构的石墨烯。单层石墨烯 (SLG) 呈现出一些独特的特性，例如光致发光 (PL)、能带隙工程等。与SLG相比，少层石墨烯（FLG）具有更高的发光强度、更慢的衰减速率和更好的可控性。在新型光电器件和透明电极的应用上更具普适性。因此，系统地研究了基于光学表征方法的少层石墨烯化学气相沉积与氧等离子体工艺之间的机理分析。在不同的氧等离子体处理时间下，对表面形貌、结构缺陷、电阻变化、化学状态和 PL 进行了追踪和研究。C _根据 X 射线光电子能谱 (XPS) 表征，FLG 表面上的 O 和 CO 键似乎随着氧等离子体蚀刻而增加然后减少。^{从 1.4 到 4.8 kΩ sq -1}呈线性方块电阻变化。除此之外，荧光特征光谱产生了明显的红移-蓝移变化。在此，全面研究了石墨烯和氧气处理的影响机制，为构建光电器件提供了潜力。