Valence Band Offset at a-B:H and a-BP:H/Si Interfaces

摘要

In order to understand the fundamental charge transport in amorphous boron heterostructure devices, we have utilized X-ray photoelectron spectroscopy to determine the valence band offset present at interfaces formed by plasma enhanced chemical vapor deposition of a-B:H and a-BP:H on Si (100) substrates. For both cases, we observed the formation of a SiB/P_x interfacial layer and relatively small valence band offsets of 0.15 ± 0.1 and —0.3 ± 0.1 eV respectively for the a-B:H/Si and a-BP:H/Si interfaces. Using previously reported values for the bandgap of a-B :H and a-BP:H, the conduction band offsets with Si were estimated to be 0.2 ± 0.2 and 1.25 ± 0.16 eV respectively.