Suppression of GeO interfacial layer and enhancement of the electrical performance of the high- gate stack by the atomic-layer-deposited AlN buffer layer on Ge metal-oxide-semiconductor devices.

For high-performance nanoscale Ge-based transistors, one important point of focus is interfacial germanium oxide (GeO ), which is thermodynamically unstable and easily desorbed. In this study, an atomic-layer-deposited AlN buffer layer was introduced between the crystalline ZrO high- gate dielectrics and epitaxial Ge, in order to reduce the formation of interfacial GeO . The results of X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy demonstrate that the AlN buffer layer suppressed the formation of interfacial GeO .