Fowler-Nordheim Current Oscillations Analysis of Metal/Ultra-Thin Oxide/Semiconductor Structures

Abstract

In this paper we present results concerning the modeling of oscillations in the I-V g characteristics (V g < 0), of metal/ultra-thin oxide/semiconductor (MOS) structures where the oxide thickness is 45 A. From the theoretical models of the literature we have shown that the modeling of oscillations cannot be made by using the conduction parameters (metal/ultra-thin oxide interface barrier, prefactor K 1 ) at low or high electric fields. However, it requires the determination and a fine analysis at low fields of the excess current which is due to the presence of defects in the oxide layer. The oscillations analysis of this excess current enabled us to show on the one hand a good agreement between the field values corresponding to the theoretical and experimental oscillation extrema, and on the other hand to estimate the defect depth.

Modelling of the influence of charges trapped in the oxide on theI(Vg) characteristics of metal–ultra-thin oxide–semiconductor structures

“…where m 0 is the mass of the free electron and f (E, T ) the Fermi-Dirac distribution that depends on the temperature T [22][23][24].…”

“…With respect to trapped charges with a density N 1 at x = X b , there exist for a given voltage V g two fields [23,24] in the oxide: one E 1 between the metal and X b , the other E 2 between X b and silicon. Using the Gauss equation, one can determine the field E 1 as a function of the charge density N 1 and field E 2 :…”

Ageing of metal/ultra-thin oxide/semiconductor structures under Fowler–Nordheim current injection

“…By using a work function of the metal equal to 2.94 eV [14,29,30], we could determine and trace the fixed charges according to the oxide thickness as shown in figure 1. This is a negative charge which is in good agreement with the results published in the literature [38][39][40].…”

“…The most frequently studied structures are those exhibiting an oxide thickness greater than 10 nm [1][2][3][4][5][6][7][8]. The MOS structures with an ultra-thin oxide thickness (<10 nm) are seldom studied [9][10][11][12][13][14][15]. These types of studies are particularly important as they cover MOS structures used in miniaturized devices [16,17] (transistor MOS, EEPROM memories, etc).…”

The Charge Transport in (2, 2) Armchair Carbon Nanotube: A Theoretical Modeling

“…This theory is derived from a wave function of quantum chemistry and therefore transformed into an exponential function. [16][17][18][19][20] The inelastic electron tunneling spectroscopy (IETS) of is widely used to determine the electronic characteristics of molecules inserted between electrodes, and has been used in the last years in concomitance with computational methods, because the both techniques showing the same trends in response to applied methods. Deriving I-V obtained by the conductance of the IET spectrum proportional to the applied electric field, successively obtains the vibrational peaks corresponding to the second derivative I-V which in fact characterizes the behavior of the material under field induced.…”