Seebeck/Peltier thermoelectric conversion device having phonon confinement layers of crystalline semiconductor containing angstrom-sized organic groups as semiconductor atoms substituents within the crystal lattice and fabrication process

Significant phonon migration restraint is achieved within a relatively homogeneous polycrystalline doped semiconductor bulk by purposely creating in the crystal lattice of the semiconductor hydrocarbon bonds with the semiconductor, typically Si or Ge, constituting effective organic group substituents of semiconductor atoms in the crystalline domains. An important enhancement of the factor of merit Z of such a modified electrically conductive doped semiconductor is obtained without resorting to nanometric cross sectional dimensions in order to rely on surface scattering eventually enhanced by making the surface highly irregular and/or creating nanocavities within the bulk of the conductive material. A determinant scattering of phonons migrating under the influence and in the direction of a temperature gradient in the homogeneous semiconductor takes place at the organic groups substituents in the crystalline doped semiconductor bulk. Fabrication processes and Seebeck-Peltier energy conversion devices are exemplarily described.