An XPS Study of the Effects of CF4 Plasmas on Gold Surfaces

Abstract
X-ray photoelectron spectroscopy has been employed to study the effect of CF4 rf plasmas on gold surfaces. The data indicate that the CF4 plasma converts the inert gold surface into a chemically active surface composed of gold, gold oxide, and gold fluoride. Upon exposure to air, the gold fluoride is hydrolyzed. The modified surface actively adsorbs water. The significance of the results is discussed in terms of microelectronic reliability considerations.