Advantages of B18H22 ion implantation and influence on PMOS reliability

In this paper, the impact of cluster ion (B₁₈H_x⁺) implantation on SDE formation are investigated in detail. It has been shown that B₁₈H_x⁺ ion implantation not only can make ultra-shallow junction for 45 nm node and beyond and but also has self-amorphization property and can reduce the channeling tail in the boron distribution without pre-amorphization implantation. In addition, B₁₈H_x⁺ ion implantation can be expected to reduce a fluctuation of MOSFETs, compared with B⁺ implantation. Cluster implantation is the reliability issue by hydrogen atom, because a large amount of hydrogen atoms are simultaneously introduced with boron into the silicon substrate. Moreover, neither the increase of junction leakage current nor influences of hydrogen which is introduced during B₁₈H_x⁺ implantation on PMOS reliability does not occur. The amorphization effect are evaluated by TEM observation and boron and hydrogen profiles by SIMS analysis.