Molecular dynamics study of implant and damage formation in low-energy boron cluster ion implantation

T. Aoki, J. Matsuo, Z. Insepov, I. Yamada
1998 International Conference on Ion Implantation Technology. Proceedings (Cat. No.98EX144)  
Cluster ion implantation using decaborane (B 10 H 14 ) has been proposed as a useful technique for shallow junction formation. In order to examine the characteristics and advantages of cluster ion implantation, molecular dynamics simulations of small B cluster and monomer implantation were performed. B 1 , B 4 and B 10 are irradiated on Si (001) substrates with acceleration energy of 230eV/atom so that B 4 and B 10 are accelerated with 0.92keV and 2.3keV, respectively. Those three show the same
more » ... implant profile and implant efficiency, which agrees with the experimental result of B 10 H 14 implantation. This result suggests that each B atom in a B cluster acts individually in similar way to a monomer ion. B clusters show the same properties in projection range and implant efficiency as the monomer whereas non-linearity is shown in damage formation. The number of displacements by one B atom once increases to the same maximum value for both a B cluster and a B monomer. However, the damage recovery process is different depending on the cluster size. Damage induced by B 10 recovers more slowly and 4 times as many displacements remain compared to B 1 8ps after impact. These displacements by B 10 clusters concentrate in the near surface region of the impact point, while the ones by B 1 reside around the implanted B atom as the end-of-range damage. This characteristic damage formation by B 10 cluster is expected to avoid transient-enhanced-diffusion of incident B atoms and achieve the formation of high-quality shallow p-type junction.
doi:10.1109/iit.1998.813919 fatcat:37f6jklpbrc2lh72l6mohaxkya