Reduction of native oxides on InAs by atomic layer deposited Al2O3 and HfO2

摘要

Thin high-u0002 oxide films on InAs, formed by atomic layer deposition, are the key to achievenhigh-speed metal-oxide-semiconductor devices. We have studied the native oxide and the interfacenbetween InAs and 2 nm thick Al2O3 or HfO2 layers using synchrotron x-ray photoemissionnspectroscopy. Both films lead to a strong oxide reduction, obtaining less than 10% of the nativenAs-oxides and between 10% and 50% of the native In-oxides, depending on the depositionntemperature. The ratio of native In- to As-oxides is determined to be 2:1. The exact composition andnthe influence of different oxidation states and suboxides is discussed in detail.