Fluctuations and noise of hot carriers in semiconductor materials and devices

After recalling the definition of the noise temperature, the macroscopic expressions for noise sources are shown not to be specific to the hot carrier regime, though dependent on the electric field strength. Careful modeling allows one to obtain important information on transport parameters from noise measurements. The microscopic noise source expressions, via the transition rates, give a unified view of the noise sources. In particular, it is clarified that noise sources are intercorrelated, and that there is also space correlations over lengths of a few mean free paths. Recent developments are reviewed, concerning noise modeling using direct numerical methods for solution of the Boltzmann equation. Finally, impedance field methods for modeling noise of devices are briefly evoked