Electron Band Alignment at Interfaces of Semiconductors with Insulating Oxides: An Internal Photoemission Study
Figure 1
Schematic of the VB offset () determination from an external photoemission experiment. While in the ideal case of the uncharged insulator (panel (a)) the energy difference between electrons emitted from the VB tops of the semiconductor and insulator exactly corresponds to the VB offset, the X-ray induced charging of the insulator (panel (b)) introduces an energy shift due to variation of the electrostatic potential across the insulating layer leading to a systematic error in the measured band offset value.
