Phosphorus monolayer doping (MLD) of silicon on insulator (SOI) substrates

Noel Kennedy, Ray Duffy, Luke Eaton, Dan O'Connell, Scott Monaghan, Shane Garvey, James Connolly, Chris Hatem, Justin D Holmes, Brenda Long
2018 Beilstein Journal of Nanotechnology  
This article is part of the thematic series "Metrology and technology computer aided design for the sub-10 nm technology node". Associate Editor: N. Motta © 2018 Kennedy et al.; licensee Beilstein-Institut. License and terms: see end of document. Abstract This paper details the application of phosphorus monolayer doping of silicon on insulator substrates. There have been no previous publications dedicated to the topic of MLD on SOI, which allows for the impact of reduced substrate dimensions to
more » ... be probed. The doping was done through functionalization of the substrates with chemically bound allyldiphenylphosphine dopant molecules. Following functionalization, the samples were capped and annealed to enable the diffusion of dopant atoms into the substrate and their activation. Electrical and material characterisation was carried out to determine the impact of MLD on surface quality and activation results produced by the process. MLD has proven to be highly applicable to SOI substrates producing doping levels in excess of 1 × 10 19 cm −3 with minimal impact on surface quality. Hall effect data proved that reducing SOI dimensions from 66 to 13 nm lead to an increase in carrier concentration values due to the reduced volume available to the dopant for diffusion. Dopant trapping was found at both Si-SiO 2 interfaces and will be problematic when attempting to reach doping levels achieved by rival techniques. 2106
doi:10.3762/bjnano.9.199 pmid:30202683 pmcid:PMC6122086 fatcat:6x3go45g2fembd2uaplyg7gc5a