Mechanism of graphene synthesis by microwave and RF plasma-enhanced chemical vapor deposition system with acetylene

Hang Hsu^1*, Syuan-Wei Lin¹, Wei-Yen Woon¹

¹physic, National Central University, Taoyuan, Taiwan

* Presenter:Hang Hsu, email:sam20000110@gmail.com

For now, the most common way to synthesis large-area graphene is thermal chemical vapor deposition (CVD). However, thermal CVD typically needs a high temperature around 1000℃ during the growth, which restricts mass production of graphene film and reduction of production cost. Therefore, the low-temperature synthesis by plasma-enhanced chemical vapor deposition (PECVD) seems to be a solution to overcome the limitation of thermal CVD. Generally, the methane plasma is used in the PECVD system for its stability. Meanwhile, the higher pyrolysis energy restricts the probability to grow graphene with low substrate temperature. Therefore, in this research, we control the acetylene plasma induced by microwave and capacitively-coupled RF systems to synthesis graphene at a lower temperature. We used the optical emission spectrum to observe the plasma state and analyzed the graphene by scanning electron microscopy, Raman spectrum, and atomic force microscopy, finding out the difference of growing mechanism at low temperature in these two systems with different ionization rates and electron temperature.

Keywords: Graphene, PECVD, Acetylene, Low-temperature growing