Sub-domain solution of the Boltzmann equation in MOS devices by means of spherical harmonics expansion

A sub-domain solution technique of the Boltzmann Transport Equation (BTE) based on the Spherical Harmonics Expansion (SHE) method is presented, and applied in the channel region of MOSFETs. It is demonstrated that by means of suitable boundary conditions the "exact" solution is well approximated, with an appreciable increase of numerical efficiency.