Effects of Post-Deposition Annealing Temperatures on the Composition of Interfacial Layer at Germanium (Ge)/Aluminium Oxide (Al2O3)

Abstract

The understanding of chemical bonding structure of high k dielectrics/Germanium (Ge) interface is upmost importance in order to form a good quality dielectric/Ge interface in fabricating Ge metal oxide semiconductor field effect transistor (MOSFETs). In addition, there is still no detail explanation on the interfacial growth of dielectrics/Ge under the influenced of different temperature of post deposition anneal. In current work, the effects of post deposition anneal (PDA) temperature between 400°C and 600°C on the chemical composition of interfacial layer between Ge and Al 2 O 3 were examined by X-ray photoelectron spectroscopy (XPS). Investigation on thermal stability and structural characteristics for gate structure of Al 2 O 3 dielectric grown on Ge by RF sputtering was done by analyzing X-ray photoelectron spectroscopy (XPS) spectra. It is observed that the oxygen deficient region in interfacial layer (IL) is enhanced rather than fully oxidized Al 2 O 3 with increased PDA temperatures. These undesired phenomena caused shrinkage of IL at Ge/Al 2 O 3 interface at higher temperature of 600°C.