Crystals (Mar 2023)

Polarization Modulation on Charge Transfer and Band Structures of GaN/MoS<sub>2</sub> Polar Heterojunctions

  • Feng Tian,
  • Delin Kong,
  • Peng Qiu,
  • Heng Liu,
  • Xiaoli Zhu,
  • Huiyun Wei,
  • Yimeng Song,
  • Hong Chen,
  • Xinhe Zheng,
  • Mingzeng Peng

DOI
https://doi.org/10.3390/cryst13040563
Journal volume & issue
Vol. 13, no. 4
p. 563

Abstract

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As important third-generation semiconductors, wurtzite III nitrides have strong spontaneous and piezoelectric polarization effects. They can be used to construct multifunctional polar heterojunctions or quantum structures with other emerging two-dimensional (2D) semiconductors. Here, we investigate the polarization effect of GaN on the interfacial charge transfer and electronic properties of GaN/MoS2 polar heterojunctions by first-principles calculations. From the binding energy, the N-polarity GaN/MoS2 heterojunctions show stronger structural stability than the Ga-polarity counterparts. Both the Ga-polarity and N-polarity GaN/MoS2 polar heterojunctions have type-II energy band alignments, but with opposite directions of both the built-in electric field and interfacial charge transfer. In addition, their heterostructure types can be effectively modulated by applying in-plane biaxial strains on GaN/MoS2 polar heterojunctions, which can undergo energy band transitions from type II to type I. As a result, it provides a feasible solution for the structural design and integrated applications of hybrid 3D/2D polar heterojunctions in advanced electronics and optoelectronics.

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