In this paper, we report on the in situ synthesis of graphene layers by means of chemical vapor deposition (CVD), directly on nickel micro-electromechanical systems (MEMS) surfaces. We have developed MEMS structures of which the temperature can be increased locally by Joule heating while in a methane environment. For our MEMS structures, the thermal time constant is 28 μs. As a result, we have control over the carbon precipitation time, thereby governing how many graphene layers are formed. Bi-layer to multi-layer graphene was observed using micro-Raman spectroscopy, but not single-layer graphene, as it gives no Raman signal when coupled on a nickel surface. The corresponding precipitation control theory is also presented in this paper, in which we relate the out-diffusion of carbon atoms from the grains of the nickel structure to the resulting number of graphene layers. Our method provides regulated carbon segregation from nickel and allows a prescribed number of graphene layers to form by tuning the precipitation time. In this way, we enable the direct in situ synthesis of graphene locally on the top and sidewalls of nickel MEMS structures, so that e.g. such graphene-coated MEMS surfaces can contribute towards a promising solution against friction and wear for MEMS devices with sliding components.

在本文中，我们就现场报告直接在镍微机电系统（MEMS）表面上通过化学气相沉积（CVD）合成石墨烯层。我们已经开发出可以在甲烷环境中通过焦耳加热局部提高温度的MEMS结构。对于我们的MEMS结构，热时间常数为28μs。结果，我们可以控制碳沉淀时间，从而控制形成了多少石墨烯层。使用显微拉曼光谱法观察到了双层至多层石墨烯，但未观察到单层石墨烯，因为当偶联在镍表面上时，它没有拉曼信号。本文还提出了相应的沉淀控制理论，其中我们将碳原子从镍结构晶粒向外扩散与石墨烯层的最终数量相关。我们的方法可控制镍中的碳偏析，并通过调整沉淀时间来形成规定数量的石墨烯层。这样，我们启用直接在镍MEMS结构的顶部和侧壁上局部地石墨烯的原位合成，因此，例如，这种石墨烯涂层的MEMS表面可以为具有滑动部件的MEMS器件带来有希望的解决方案，以防止摩擦和磨损。