Energy generation and transport in sub-micrometer electronic devices do not obey continuum laws such Ohm's law and Fourier's law. It is proposed to study such processes both theoretically and experimentally. The theoretical model considers the electrons, optical phonons and acoustic phonons to be three thermodynamic systems which exchange energy between themselves. The constitutive relations for heat and particle fluxes are obtained from the Boltzmann transport equation. With appropriate conservation laws the model will predict the temperatures of electrons, optical phonons and acoustic phonons, as well as density of charge carriers and electrical conductivity. The experimental effort will focus on developing a new technique of nanometer-scale temperature measurement, making use of the atomic force microscope. The measured temperatures will be compared with theoretical predictions.