1/f NOISE COMPONENT CONDITIONED BY BUILT-IN ELECTRIC FIELD IN SEMICONDUCTORS

Abstract

The influence of the built-in electric field on the low-frequency current fluctuations in n-type non-degenerate homogeneous semiconductors at presence of constant external electric and magnetic fields is examined. The problem is considered by means of Langevin-type Boltzmann transport equations for the electron and phonon systems at domination of electron–acoustic phonon scatterings. For the first time, it is shown that within the context of the introduced problem, the spectral density of the current noise contains 1/f component specified by the built-in electric field. By form it is similar to the empiric Hooge formula. On the basis of the computations, a model explaining the physical mechanism of the origin of the additional component of 1/f noise, conditioned by the presence of the built-in electric field in semiconductor, is proposed. For the Hooge parameter, a comparison with the experimental data of generally observed 1/f noise for Si samples is carried out. The comparison shows that at some "favorable" conditions, the level of this new component of the 1/f noise can reach the level of the generally observed 1/f noise.