Band offsets at amorphous hydrogenated boron nitride/high-k oxide interfaces from x-ray photoelectron spectroscopy with charging effects analysis

To facilitate the design of heterostructure devices employing hexagonal (sp(2)) boron nitride, x-ray photoelectron spectroscopy has been used to determine the valence band offsets (VBOs) at interfaces between amorphous hydrogenated sp(2) boron nitride (a-BN:H) and atomic-layer-deposited high-dielectric-constant (high-k) aluminum oxide (Al2O3) and hafnium oxide (HfO2). After consideration of the effects of charging and differential charging, including with dual-beam charge compensation, the VBOs for Al2O3/a-BN:H and HfO2/a-BN:H interfaces were determined to be 1.9 +/- 0.2 and 1.4 +/- 0.2eV, respectively. Additionally, the conduction band offsets at the Al2O3/a-BN:H and HfO2/a-BN:H interfaces were determined, based on literature-reported bandgaps for the respective materials, to be -1.0 +/- 0.3 and -1.1 +/- 0.3eV, respectively, indicating type II band alignment in both cases.