Electron transport in InN layers grown by plasma-assisted molecular beam epitaxy

Hall effects were measured as functions of temperature on unintentionally doped InN layers grown by plasma-assisted molecular beam epitaxy, and the results were analyzed by numerically solving the Boltzmann equation with various scattering mechanisms. The electron density increases with the dislocation density and is in a range of 1.8 - 10.2 x 10(18) cm(-3) at room temperature. Scattering due to edge dislocations is the most important in the sample with the lowest electron density and becomes negligible in the other samples with a higher electron density. Instead, space-charge scattering, which is ignored in the above dislocation-dominant sample, becomes significant in the samples with electron densities near mid 10(18) cm(-3). This space-charge scattering may be ascribed to a random distribution of edge dislocations. Ionized impurity scattering is predominant over the entire temperature range for the sample with the highest electron density.