(Invited) Nickel and Nickel-Platinum Silicide for BiCMOS Devices

Abstract

The world’s fastest SiGe HBT was presented by Heinemann et al. at IEDM 2016, which was achieved among other measures by NiSi application. The BiCMOS integration of such HBTs requires a careful NiSi adjustment with respect to MOSFET leakage currents. The goal of this paper is to find out a NiSi or NiPtSi process, which results in low RS to increase fmax without degradation of MOSFET leakage currents. An fmax rise is demonstrated by a reduction of NiSi or NiPtSi RS to 4 Ω. A further RS lowering to 1.6 Ω with a corresponding fmax increase was achieved by NiSi layers formed by two-step 300/450°C anneals, which generate elevated MOSFET leakage currents. They can be inhibited for NiSi formed by 200/450°C anneals at the expense of elevated RS. NiPtSi significantly suppresses silicide pipes to the MOSFET channel even for 300/450°C anneals and is a promising choice for upcoming BiCMOS technologies.