Generalized-stacking-fault energy of sphalerite structure GaN: A first principles calculation

As a third-generation semiconductor material, GaN has wide bandgap, strong atomic bonds, and other properties, so its research and application is currently the frontier and hot spot of global semiconductor research. In the process of preparing GaN, it is inevitably accompanied by a large number of crystal defects, and stacking fault is one of the surface defects. The energy absorbed or released during the generation of stacking fault is called the generalized-stacking-fault energy. In this work, using first-principles calculation, we systematically explored the generalized stacking fault energies and their variation with the slip distance when three different planes of sphalerite GaN slip in different directions. The results indicate that the (111) plane as a close-packed plane, its slippage is more likely to occur than the other two planes. On the (111) plane, the difficulty of slipping in the <01 1‾ > and <1‾ 10> directions is the same, and it is easier to slip than in the <2‾ 11> direction. On the (100) plane, it is easier to slip in the <1‾ 01> direction compared to the <001> and <1‾ 00> directions. On the (110) plane, the <011‾ > direction is the easiest to slip, and the <111‾ > direction is the hardest to slip. < 2‾ 11>(111) is easier to decompose than <11 1‾ >(110). The results can help to optimize the material properties and avoid formulating of stacking faults in the growth, processing, and heat treatment of GaN crystals.