Synthesis of Graphene from Epoxies using a Short-Duration High-Intensity Light Flash
Post date: October 4, 2020
Student: Shenghao Wu
Faculty: Timothy S. Fisher
Summary: Heat generation in integrated circuits (IC) will lead to the temperature increase that may affect the normal behavior of semiconductor devices. As such, effective heat dissipation is highly demanded especially when the semiconductor devices keep miniaturizing. Epoxy materials are mostly used for the mass production of printed circuit board (PCB) that holds electronic circuits together. However, the thermal conductivity of epoxy materials is very low (0.15 to 0.25 W m−1 K−1) in comparison to alternative materials (ceramics and metals that are expensive). Therefore, most manufacturers have to develop advanced thermal management techniques and methods to maintain the temperature of PCBs and their active components with a safe operational range.
Video 1. The operation process of the high-intensity light flash method
We proposed a high-intensity light flash method to synthesize highly-conductive graphene layers by converting the benzene rings of epoxy materials to graphitic form. A customized solar simulator was employed to generate the high-intensity light flash whose peak irradiation can reach more than 4000 kW m−2. When a short-duration (≤1 s) high-intensity light flash reaches the epoxy plate, a localized ultra-high temperature (more than 2000 °C) is produced at the surface while there is no enough time for the material to expand or release heat. As a result, the localized ultra-high temperature enables the transformation process of graphitization and produces a thin graphene layer with a thickness of several microns. Then, the highly-conductive graphene layers are embedded in the PCB and improve its thermal conductivity and heat dissipation behaviors.
Figure 1. (Left) Converting the epoxy into graphitic form after the treatment of the short-duration high-intensity light flash. (Right) Raman characterization shows the well-graphitized structures (relevant to the D, G, 2D, and D+G peaks).