Surface evolution of very high dose arsenic implants in silicon formed by plasma immersion ion implantation - a long term study

Abstract

The evolution of very high dose arsenic implants in silicon formed by plasma immersion ion implantation and deposition (PIIID) using a non-pulsed plasma source was studied over a time period of more than one year. The study focused on the effect of arsenolite micro-crystal formation, enhanced oxidation, and the significant As dose loss from as implanted samples at room temperature. The study was carried out combining analytical evidence from SIMS, XPS, INAA, SEM, and optical microscopy suggesting a two stage process of As dose loss, the first implying arsenolite crystal growth and the second an out-diffusion. In fact, comparison of samples fabricated using different PIIID parameters showed that crystal growth seems not to be the only process responsible for dose loss.