Low-frequency noise in thick-film resistors due to two-step tunneling process in insulator layer of elemental MIM cell

In this paper, it is assumed that low-frequency noise source in thick-film resistors are fluctuations of the trap occupations by electrons, tunneling through insulator layer of the elemental cell. Two conducting particles separated by a thin insulating layer form the elemental cell (MIM structure). Trap charge fluctuations are modulating the MIM cell barrier, thus modulating the tunneling current and barrier resistance. A low frequency noise model is proposed under the assumption that the space distribution of traps in thick-film resistor is symmetrical with respect to the central plane of the MIM cell. Numerical results show that in the presence of small number of traps in insulator layer of the elemental cell, 1/f noise is exhibited in a narrow frequency range (4-5 decades). A model is applied on the experimental results for noise in thick-film resistors and a method of evaluation of the trapping state´s parameters is discussed based on noise measurements