Suppression of parasitic bipolar action in ultra-thin-film fully-depleted CMOS/SIMOX devices by Ar-ion implantation into source/drain regions

This paper proposes a new technique that can effectively suppress the parasitic bipolar action (PBA) in ultrathin-film fully-depleted (FD)nMOSFET´s/SIMOX with a floating body. In this technique, recombination centers are created in the source and drain (S/D) regions by deep Ar-ion implantation. They act to reduce the number of holes that accumulate in the body region by increasing the hole current flowing from the body region into the source region. Consequently, the rise of the body potential is lowered, and the parasitic bipolar action can be suppressed. A 0.25-μm gate nMOSFET/SIMOX fabricated with an Ar dose of 2×10¹⁴ cm^-2 exhibited excellent improvements in electrical characteristics: a reduction in the off-leakage current of over two orders of magnitude and an increase in the drain-to-source breakdown voltage beyond 0.6 V