The deformation mechanism of gallium-faces and nitrogen-faces gallium nitride during nanogrinding

Abstract In this study, the deformation mechanism of gallium-faces (Ga-faces) and nitrogen-faces (N-faces) gallium nitride (GaN) during nanogrinding were investigated by molecular dynamics (MD). The differences between the two were analyzed from force, temperature, potential energy, surface/subsurface damage, and material removal rate (MRR). The results show that N-faces GaN withstand lower grinding force, higher temperature, potential energy, and MRR. Meanwhile, the total length of dislocations and the number of zinc blende phase atoms are also greater than those in Ga-faces. Further research found that the difference in edge dislocation with b = 1/3 〈11–20〉 is the main reason that causes the dislocations in N-faces longer than that in Ga-faces, which can reach about 3 times. However, the Shockley incomplete dislocation with b = 1/3 〈1–100〉 and other dislocations are slightly smaller than those in Ga-faces. This study innovatively researched the difference in the processing properties of the two GaN at the nano-scale, which provide a theoretical basis for guiding GaN in the processing of ultra-precision.