Abstract
Processes that achieve FL depinning for metal/n-Ge1-xSnx (1019 cm-3) contact were proposed for different technologies. For typical metal contact, O2 plasma treatment on Ge1-xSnx surface prior to metal contact is a more effective way for the purpose than other treatments since the formed GeSnOx has the desirable EG, ΔEc and κ value with the capability to passivate interfacial dangling bonds. For those require stanogermanide, YbGe1-xSnx formed by annealing of GeSn-capped Yb also exhibits ohmic conduction behavior due to interface states suppression. Both processes obtain low ρc of ~10-7 Ω-cm2 and ΦBN of ~0.1 eV, empowering next-generation GeSn technology.