English

Giant polarization charge density at lattice-matched GaN/ScN interfaces

Materials Science 2019-12-23 v2

Abstract

Rocksalt ScN is a semiconductor with a small lattice mismatch to wurtzite GaN. Within the modern theory of polarization, ScN has a nonvanishing formal polarization along the [111] direction. As a result, we demonstrate that an interface between (0001) GaN and (111) ScN exihibts a large polarization discontinuity of -1.358 Cm2\rm Cm^{-2}. Interfaces between ScN and wurtzite III-nitrides will exhibit a high-density electron gas on the (0001ˉ\bar{1}) GaN interface or a hole gas on the (0001) GaN interface, with carrier concentrations up to 8.5×10148.5 \times 10^{14} cm2^{-2}. The large polarization difference and small strain makes ScN a desirable choice for polarization-enhanced tunnel junctions within the III-nitride materials system. The large sheet carrier densities may also be useful for contacts or current spreading layers.

Keywords

Cite

@article{arxiv.1910.00142,
  title  = {Giant polarization charge density at lattice-matched GaN/ScN interfaces},
  author = {Nicholas L. Adamski and Cyrus E. Dreyer and Chris G. Van de Walle},
  journal= {arXiv preprint arXiv:1910.00142},
  year   = {2019}
}

Comments

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Applied Physics Letters {\bf 115}, 232103 (2019) and may be found at https://aip.scitation.org/doi/10.1063/1.5126717