Band alignment of atomic layer deposited high-k Al2O3/multilayer MoS2 interface determined by X-ray photoelectron spectroscopy.

The energy band alignment between Al 2 O 3 /multilayer (ML)-MoS 2 was characterized using high-resolution x -ray photoelectron spectroscopy (XPS). The Al 2 O 3 was deposited using an atomic layer deposition (ALD) tool. A valence band offset of 4.10 eV and a conduction band offset of 3.41 eV were obtained across the ALD-Al 2 O 3 /ML-MoS 2 interface. For comparison, the valence band offset and a conduction band offset were also obtained for ALD-SiO 2 /ML-MoS 2 interface. It was found out that ALD-Al 2 O 3 /ML-MoS 2 interface has a larger conduction band offset, compared to that of ALD-SiO 2 /ML-MoS 2 interface, which indicate ALD-Al 2 O 3 served as the gate dielectric for n-type ML-MoS 2 based field effect transistors has advantage over ALD-SiO 2 in term of suppressing the gate leakage current. [ABSTRACT FROM AUTHOR]