Removal of native silicon oxide with low-energy argon ions

Electron cyclotron resonance argon plasmas have been used to clean native silicon oxide at low (≊100 eV) ion energies. In situ x-ray photoelectron spectroscopy (XPS) allowed us to evaluate the effectiveness of this process by studying the Si 2p and O 1s photoemission spectra. Results indicate complete and rapid removal of chemically bound oxygen to silicon and the presence of small levels of adsorbed or interstitially implanted oxygen. Implanted argon was detected by XPS; however, the concentration appears to be greatly reduced by operating under low substrate bias conditions.