Surface Modification of Polyimide Sheets by 13.56 MHz-Radio Frequency-Powered O2/Ar Plasma
Abstract
Polyimide (PI) sheet’s surface was treated in admixtures of oxygen (O2 )/argon (Ar) plasma excited by 13.56 MHz radio frequency power. Contact angle and surface free energy of the PI sheet samples were measured to assess changes in the hydrophilicity after plasma exposure. The surface morphology of the samples was characterized by atomic force microscopy (AFM), and a Fourier transform infrared spectrometer (FT-IR) was used to determine the IR spectra. O2 and Ar plasma treatment was found to increase the hydrophilicity and surface free energy of PI sheet, which was supported by increased roughness and changes in the spectra for polar groups on the surface. The results showed that 0.50-O2:0.50-Ar is the optimum admixture of O2/Ar gas during plasma treatment of PI sheet.