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Band line-ups and band-gap behaviour of new-type superlattices (3C-BN)/(2H-BN), (3C-GaN)/(2H-GaN) and (3C-SiC)/(2H-SiC)

1996; IOP Publishing; Volume: 8; Issue: 49 Linguagem: Inglês

10.1088/0953-8984/8/49/012

1361-648X

San-huang Ke, Kaiming Zhang, Xide Xie,

Ga2O3 and related materials

We report ab initio calculations of the electronic structures and the band line-ups of heterocrystalline superlattices (HSLs) , and (n = 1,2,3). The band line-ups at both the (3C-BN)/(2H-BN) interface and the (3C-SiC)/(2H-SiC) interface are found to be type II, with valence-band offsets of 0.16 eV and 0.14 eV and conduction-band offsets of up to 1.56 eV and 1.08 eV respectively. For the (3C-GaN)/(2H-GaN) interface, the valence-band offset is found to be almost zero, and the conduction-band offset is about 0.4 eV. It is found that the band gaps in the HSLs decrease rapidly with the increase of the slab thickness. This `abnormal' band-gap behaviour is shown to be due to the internal electric fields induced by the spontaneous polarizations in the 2H structures.