Selenium Co-implantation and segregation as a new contact technology for nanoscale SOI N-FETs featuring NiSi:C formed on Silicon-carbon (Si:C) source/drain stressors

Abstract

We report a novel contact technology comprising Selenium (Se) co-implantation and segregation to reduce Schottky barrier height ΦBn and contact resistance for n-FETs. Introducing Se at the silicide-semiconductor interface pins the Fermi level near the conduction band, and achieves a record low ΦBn of 0.1 eV on Si:C S/D stressors. Comparable sheet resistance and junction leakage are observed with and without Se segregation. When integrated in nanoscale SOI n-FETs with Ni-silicided Si:C S/D, the new Se-segregation contact technology achieves 36% reduction in total series resistance and 32% ION enhancement. Linear transconductance GMLin also shows large enhancement in the sample with Se-segregated contacts. © 2008 IEEE.