Influence of Deposition Temperature on Amorphous Carbon Thin Films from Mushroom Waste Oil using Chemical Vapor Deposition (CVD)

Amorphous carbon has attracted a lot of interest because of its unique properties, which make it highly promising in various fields. Nevertheless, the growth parameters for this material are still not well understood, presenting a considerable challenge, especially when utilizing a novel ‘green’ alternative as a carbon precursor. The deposition temperature, one of the crucial parameters, is recognized to influence the properties of amorphous carbon. Thus, this study focused on the effect of deposition temperature on the structural and electrical properties of the resulting thin films produced from a novel natural oil precursor. In this work, the oyster mushroom waste was extracted into oil using Soxhlet, which was then used as a carbon precursor with silicone as a substrate. By using chemical vapor deposition (CVD), amorphous carbon thin films were successfully deposited at different deposition temperatures ranging from 650°C to 950°C for 30 minutes. Energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and current-voltage (I-V) measurement were used to characterize the thin films. From the findings, it can be confirmed that the thin films are amorphous carbon due to the existence of the sp2 and sp3 carbon bonds, and the D and G peaks in the Raman spectra. The results further demonstrate that when the deposition temperature increases, the electrical conductivity and carbon percentage of the a-C thin films increase. Along with a high intensity ratio (ID/IG) and carbon percentage, the highest electrical conductivity, 1.41 × 10² S·cm-¹, was found to be deposited at 850°C. This indicates that a deposition temperature of 850°C is ideal for producing amorphous carbon thin film derived from a natural oil that had not been previously introduced.