Ge Devices: A Potential Candidate for Sub-5-nm Nodes?

In this article, we explore different device and standard cell architectures for scaling the Germanium fin field-effect transistor (FinFET) and nanosheet (NS) at the sub-5-nm node. It is demonstrated that the Germanium device provides approximately 70% improvement in drive current and 3.4x less device resistance. The main concern for Germanium devices remains the high leakage current due to the gate-induced drain leakage, which limits their usage to high-speed applications. Overall, Germanium devices require fewer boosters than silicon to scale beyond the 5-nm node. Contact resistivity is found to be a critical knob for Germanium and it can be relaxed to 3e-9 Omega cm(2) to meet the power and performance targets for the sub-5-nm node. Moving to the NS helps in relaxing this constraint further.