Evaluation of structural, electronic, optical, elastic, and mechanical properties of triclinic Sn-doped Ga2O3 using density functional theory

The electronic bandgap, density of states, optical coefficients, elastic constants, and bulk-to-shear ratio of Sn-doped Ga2O3 were calculated using density functional theory. The result of our study shows that a wide bandgap of 3.761 eV has been reported, which is found larger than the band energy Eg of 2.28 eV from our previous study in bulk Ga2O3. We also discovered the bandgap energy Eg reduces with the Sn chemical decompositions inside superlattice cell, and bandgap energy become direct when there are three unit-cells inside the doped superlattice. The bulk-to-shear ratio of 1.79 confirming the presence of the material ductility. Surprisingly, the Poisson's ratio of the Sn-doped Ga2O3 is in close match to the bulk Ga2O3 lattice bulk, which are both found to be ionic-covalent. We showed that, with our doped structure model, our computed elastic coefficients, bulk (shear) modulus, Poisson's ratio, and bulk-to-shear ratio provide different values (though not significant) to the bulk-lattice Ga2O3. This work aims to stimulate more research studies towards devices such as MOSFETs.