70 nm NMOSFET Fabrication with 12 nm n+-p Junctions Using As2+ Low Energy Implantations

Abstract

Nano-scale gate length metal oxide semiconductor field effect transistor (MOSFET) devices require extremely shallow source/drain extension regions with junction depth of 20–30 nm [The International Technology Roadmap for Semiconductors: Semiconductor Industry Association (1998)]. In this work, 12 nm n+-p junctions that are realized by using As2+ low energy (≤10 keV) implantation show the low sheet resistance of 1.0k Ω/□ after a rapid thermal annealing process. The As2+ implantation and RTA process make it possible to fabricate the nano-scale n-type metal oxide semiconductor field effect transistor (NMOSFET) with gate length of 70 nm. The As2+ 5 keV NMOSFET shows a small threshold voltage roll-off and a DIBL effect of 30 mV at 100 nm gate length NMOSFET devices.