Long range pinning interaction in ultra-thin insulator-inserted metal/germanium junctions

In this paper, we discuss the Fermi Level Pinning (FLP) modulation at metal/germanium (Ge) interface by inserting ultra-thin insulator film. The FLP was alleviated gradually and continuously with increasing insulator (GeO
₂
) thickness up to 2 nm. The results cannot be simply explained by the termination of dangling bonds or defects just at Ge interface. It is inferred that relatively long range (~ 2 nm) interaction between metal and Ge might be involved in the FLP and its alleviation.