Abstract
The effect of mass anisotropy on the thermoelectric figure of merit in the presence of polar optical phonon (POP) scattering is numerically studied. Electron transport is considered using the linear Boltzmann transport equation. The mass anisotropy is advantageous for the figure of merit along the principal directions of a small effective mass if phonon thermal conductivity is large. Inelasticity plays an essential role in the obtained result. The result is qualitatively different from that for an ionised impurity model.