A first-principles study of MgSnN₂ films using a DFT-1/2 approach

Abstract

The thin films of a newly discovered MgSnN$_2$ Pnma phase was studied using a recently developed DFT-1/2 functional. It was showing that the properties of the investigated films closely relate to the thickness. For those films with odd number of layers, the band gaps are accordingly 2.040 eV, 2.102 eV and 2.107 eV for three, five and seven layers, showing an increasing order along with depth. As for those with even number of layers, the band gaps show a reduction from 2.488 eV for double layer to 2.210 eV for four-layer and then to 2.136 eV for six-layer. The change of the band gap mainly comes from the bonding relation between the outmost surface layer and the secondary surface layer, and also due to the layer spacing and interlayer interaction strength. Moreover, the absorption spectra shows promising absorption peaks within visible range. Therefore, fabrication of films with thickness control can potentially be used to expand the applications of MgSnN$_2$ for energy harvest and semiconductors in device design.

An Ab Initio Investigation of CdSnN2Under Uniaxial Compressions

“…Based on this, thickness-dependent thin films were constructed and studied on their electronic properties. [31,32] In another work, [33] we investigated the behavior of CdSnN 2 under hydrostatic pressure and found that it undergoes a structural transition and a semiconductor-metal transition when pressurized to 14 GPa as well as a metal-semiconductor transition occurring at 20 GPa.…”