Formation of Source/Drain extension by Antimony implantation for high performance DRAM peripheral transistors

We have investigated properties of Antimony implanted Si such as crystalline defect, dopant distribution, and sheet resistance before and after annealing using TEM, SIMS, and 4-point probe. The sheet resistance of Sb implanted Si shows 35% lower than Arsenic, even though junction depth is 25% shallower. Electrical behaviors of Sorce/Drain extension implanted with Sb show 10% improvement of Ion/Ioff characteristics without degradation of drain-induced barrier lowering compared to the As.