One-Pot Fabrication of Silicon Carbide Thin Films via Plasma-Enhanced Chemical Vapor Deposition (PECVD) Followed by In Situ Pyrolysis

Abstract

Silicon carbide (SiC_x) thin films are recognized as important materials because of their outstanding characteristics, such as chemical resistance in corrosive environments, a low thermal expansion coefficient, remarkable hardness, and high thermal conductivity. Due to such exceptional properties, these materials find a wide range of applications in the energy, semiconductor, biomedical, and aerospace industries. The current techniques for the production of SiC_x films involve preceramic film deposition followed by transfer to a furnace for pyrolysis, which faces challenges such as poor film quality, susceptibility to oxygen contamination, high operating cost, and lengthy processing time. In this study, we fabricate SiC_x thin films, instead, by combining preceramic film deposition and pyrolysis in a single reactor. This one-step system improves energy efficiency, minimizes processing time during ceramic film production, and reduces potential contamination. Specifically, we deposited an organosilicon poly(vinylphenyldimethylsilane) film via a low-energy plasma-enhanced chemical vapor deposition (PECVD) technique followed by in situ pyrolysis employing a custom-designed microheater system placed inside the vacuum PECVD chamber. Fourier transform infrared and X-ray energy-dispersive spectroscopy results confirmed that the SiC_x film produced via in situ pyrolysis has a lower oxygen content compared to samples that were produced via ex situ pyrolysis after removal from the reactor, thus highlighting the importance of in situ pyrolysis in preventing unwanted oxidation reactions. In summary, the one-pot synthesis technique reduces contamination and oxidation and simplifies the deposition and pyrolysis process, enabling multilayer deposition and pyrolysis in a single batch system with precise control over the composition of each layer.