Pulsed laser annealing of silicon-carbon source/drain in MuGFETs for enhanced dopant activation and high substitutional carbon concentration

Abstract

We report for the first time, the use of pulsed laser annealing (PLA) on multiple-gate field-effect transistors (MuGFETs) with silicon-carbon (Si1-xCx) source and drain (S/D) for enhanced dopant activation and improved strain effects. Si1-x Cx S/D exposed to consecutive laser irradiations demonstrated superior dopant activation with a ∼60% reduction in resistivity compared to rapid thermal annealed S/D. In addition, with the application of PLA on epitaxially grown Si0.99C 0.01, substitutional carbon concentration Csub increased from 1.0% (as grown) to 1.21%. This is also significantly higher than the Csub of 0.71% for rapid thermal annealed Si0.99 C0.01 S/D. With a higher strain and enhanced dopant activation, MuGFETs with laser annealed Si0.99C 0.01 S/D show a ∼53% drain-current improvement compared to MuGFETs with rapid thermal annealed Si0.99C0.01 S/D. © 2008 IEEE.