CONTROL OF CURRENT TRANSPORT IN SCHOTTKY DIODE USING THE QUANTUM DOTS

Abstract

SummaryPurpose. In the framework of the drift-deformation-diffusion approximation considering the self-consistent boundary conditions, investigate the current-voltage characteristic (CVC) of surface-barrier structure of type Schottky with built layer of quantum dots and establish the criteria for the technological parameters of surface-barrier structure of type Schottky with built layer of quantum dots at which current-voltage characteristic has S-shaped character. Research methods. Method of self-consistent boundary conditions. Research results. As seen from the numerical calculations, the current-voltage characteristic (CVC) of low barrier (åV5.0≤Δ) Schottky diode with built layer of quantum dots in the space charge region is S-shaped nature. With increasing barrier height Δ to 0.9 eV the area of negative differential resistance on CVC is disappears, and in the interval of voltages 0.5V - 1V has exponential character. Variation of thickness i- layer (0d0RLL−=) of  toA150 leads to changing the character of CVC, i.e. the instability current of S-type is disappears. In this work the results of numerical calculations of CVC for the direct direction of displacement at two values of temperature (T = 77 K, 300K) is given. As seen from the graphs CVC in the range of the voltages Â52.0VÂ24.0<< the value of the current density of voltage at T=77 K is smaller than at T=300K.Conclusions1. It is established that current-voltage characteristic (CVC) of low barrier (åÂ5.0≤Δ) Schottky diode with built layer of quantum dots in the space charge region is S-shaped nature, when the layer of quantum dots is located at distances from the boundary of the contact metal-semiconductor of the order of (10-30)0a, where 0a is the period lattice of the semiconductor.2. It is shown that both the increasing barrier height Δof 0.5 eV to 0.9eV, and the distance from the metal to layer of QD (dL) of A50 to A150, the area of negative differential resistance on CVC is disappears.3. At high potential barrier (0.9eV) the contact effects is dominate and the site of the exponential dependence on voltage (0.5V-1V) on CVC is present, and the lower potential barrier the dependence of current on voltage is approximates to a quadratic (V> 0.6B).