Advantages of B/sub 18/H/sub 22/ ion implantation and influence on PMOS reliability

Abstract

In this paper, the impact of cluster ion (B/sub 18/H/sub x//sup +/) implantation on SDE formation are investigated in detail. It has been shown that B/sub 18/H/sub x//sup +/ 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, B/sub 18/H/sub x//sup +/ ion implantation can be expected to reduce a fluctuation of MOSFETs, compared with B/sup +/ 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 B/sub 18/H/sub x//sup +/ implantation on PMOS reliability does not occur. The amorphization effect are evaluated by TEM observation and boron and hydrogen profiles by SIMS analysis.