The effect of high-dose nitrogen plasma immersion ion implantation on siliconesurfaces

Abstract

The effect of plasma immersion ion implantation (PIII) treatment onsilicone surfaces was investigated by x-ray photoelectron spectroscopy (XPS),Fourier transform infrared spectroscopy (FTIR-ATR), and scanning electronmicroscopy (SEM). Low-energy (at voltages of 4 and 8 kV) and high-fluence (8×1017 cm-2) implantation of nitrogen was performed using an inductivelycoupled plasma source (ICP) at low pressure (~0.03 Pa). The IR absorptionspectra showed a significant decomposition in the CH3, Si-CH3, and C-F groupsof the silicone surface after PIII treatment. The percentage of decompositionwas dependent on the implantation energy. The XPS C 1s spectra of the PIIImodified surfaces showed an increase in the polar carboxyl (O-C=O) groups anda decrease in the CF3 groups. PIII treatment shifted the XPS Si 2p peak ofsilicone to a higher binding energy (around 103.2 eV) and the N 1s peak tolower binding energy (around 398.5 eV). The modified Si 2p, N 1s, and O 1sspectra suggest the formation of SiOx phases, silicon oxynitrides, and siliconnitrides on the silicone surface after PIII treatment.