Surface Contamination of Silicon Produced by Ion Implantation

Surface contamination of silicon produced by ion implantation is examined by ESCA, IMA and ESR methods, and the following results are obtained. 1) The contaminant film thickness can be evaluated by using ESCA method. 2) The deposition rate of the film increases with increase in the ton current density below 10 µA/cm 2 , and decreases with the Jon current density above 10 µA/cm 2 . The deposition rate increases with increase in the partial pressure of hydrocarbons in the vacuum system, and with decrease in the ion energy and substrate temperature. 3) Surface contamination produced by ion implantation results from polymerization of hydrocarbon molecules, which mainly originates from the diffusion pump oil. 4) A paramagnetic center with g =2.0030 is identified to be an amorphous carbon center. The origin of this center is due to the contaminant film.