Abstract Reliability is one of the key specifications of a system. For graphene synthesis by chemical vapor deposition (CVD), previous studies have shown that a trace amount of oxidants can significantly affect graphene growth, either positively or negatively. Other than deliberately introducing oxygen, oxidant impurities may be introduced by the air leaked into the system or from impurities of the reaction gases, which are normally constant and can be balanced by hydrogen and carbon precursors. Here we report a systematic investigation on the effects of Cu contamination on graphene growth, which is very common due to Cu evaporation at high temperature. The accumulated Cu deposited on the quartz tube are inevitably oxidized to form Cu2O and CuO, which result in an introduction of water either due to the desorption of water adsorbed on the rough surface or the reduction of oxides by hydrogen and methane. In addition, the introduction of water in this way is not constant, leading to a non-steady state for graphene growth and may significantly reduce the system reliability. Our finding brings caution to the study on graphene synthesis and the development of its industrial production.

中文翻译：

---

Cu污染对化学气相沉积法合成石墨烯系统可靠性的影响

摘要 可靠性是系统的关键指标之一。对于通过化学气相沉积 (CVD) 合成石墨烯，先前的研究表明，微量的氧化剂可以显着影响石墨烯的生长，无论是积极的还是消极的。除了故意引入氧气之外，氧化剂杂质可能由泄漏到系统中的空气或来自反应气体的杂质引入，这些杂质通常是恒定的并且可以通过氢和碳前体来平衡。在这里，我们报告了一项关于铜污染对石墨烯生长影响的系统研究，由于铜在高温下蒸发，这很常见。沉积在石英管上的累积Cu不可避免地被氧化形成Cu2O和CuO，由于吸附在粗糙表面上的水的解吸或氢气和甲烷对氧化物的还原，从而导致水的引入。此外，以这种方式引入的水不是恒定的，导致石墨烯生长不稳定，并可能显着降低系统可靠性。我们的发现为石墨烯合成的研究及其工业生产的发展带来了警示。