Scattering mechanisms in InN

Abstract

The effect of scattering mechanisms on the published Hall electron mobility data has been investigated, in detail, as a function of temperature. The important mechanisms of electron scattering considered are those by charged dislocations, ionized impurities, polar optical phonons, and bulk acoustic phonons via deformation of the potential and piezoelectric fields. The results are discussed using a theoretical model that takes into account the most important scattering mechanisms within the framework of the Boltzmann transport equation. We show that the dominant contribution to the mobility is found to be from dislocations via the coulomb interaction at low temperatures. The mobility versus carrier density at room temperature for various dislocation densities has been plotted, and we estimated the dislocation density. The best fit to the experimental data is obtained for a dislocation density of N-dis congruent to 2.85 x 10(13) m(-2). The polar optical phonon scattering seems to dominate at high temperatures. The results were compared with the experimental data, and we found a reasonable correlation. Also the calculated mobility agrees reasonably well with the published Hall mobility calculated using the variational principle by Chin et al.