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Electronic processes in a semiconductor system consisting of some resonant tunneling structures, built in the depletion region of a Schottky barrier, are investigated. It is shown that the Schottky barrier can block or unblock the resonant tunneling current effectively. Tunneling processes do reveal the coherent character. Sharply nonlinear current–voltage characteristics are observed for both the forward and the reverse branches.

In this paper, the effect of porosity on reverse bias current–voltage characteristics of PtSi/por-Si (p-type) IR detector as a function of temperature is investigated. Our experimental data for two samples with different porosities (50% and 10%) at 300 K and 77 K are reported by Raissi et al.¹ These data indicates a breakdown-like behavior. Our analytical model is based on hole thermionic emission with large ideality factor (n ≈ 200). Our calculations show that at each temperature, the Schottky barrier height, as well as the ideality factor, in sample with 10% porosity is bigger than that of 50%. These variations could be due to band gap variations of Si size effect using quantum dot model, and the presence of the relatively high (~10¹⁵ cm^-2 eV^-1) density of states at the silicide/por-silicon interface, respectively.

Nanoscale structure ZnO/BaTiO₃/ZnO multilayer was fabricated on silicon (Si) substrate by RF magnetron sputtering system. The light-modulated resistive switching characteristics in ZnO/BaTiO₃/ZnO devices were observed. The light-modulated resistive switching shows good repeatability at room temperature.

Pd/Si_0.9Ge_0.1/Si Schottky barrier diodes subjected to irradiation are characterized using capacitance and conductance measurements performed under forward and reverse bias while varying the temperature and frequency. The C–V technique has been used in particular to determine the carriers profile as well as the interface state density and its energy distribution.

The Schottky barrier type Ni/$n$-GaAs contacts fabricated by us were thermally annealed at 600${}^{\circ }$C and 700${}^{\circ }$C for 1min. The apparent barrier height ${\mathrm{\Phi }}_{\mathrm{\text{ap}}}$ and ideality factor of the diodes were calculated from the forward bias current–voltage characteristic in 60–320K range. The ${\mathrm{\Phi }}_{\mathrm{\text{ap}}}$ values for the nonannealed and 600${}^{\circ }$C and 700${}^{\circ }$C annealed diodes were obtained as 0.80, 0.81 and 0.67eV at 300K, respectively. Thus, it has been concluded that the reduced barrier due to the thermal annealing at 700${}^{\circ }$C promises some device applications. The current preferentially flows through the lowest barrier height (BH) with the temperature due to the BH inhomogeneities. Therefore, it was seen that the ${\mathrm{\Phi }}_{\mathrm{\text{ap}}}$ versus ${(2kT)}^{-1}$ plots for the nonannealed and annealed diodes showed the linear behavior according to Gaussian distributions.

For quantitative estimation of the degree of electrical disorder (electrical inhomogeneity) in ZnO varistor ceramics caused by a variation in the barrier height at different grain boundaries in a sample, the comparison of threshold electric fields (onsets of highly nonlinear current–voltage characteristics) in ceramics and single grain boundary (GB) is suggested and approved. At dc degradation similar behavior of the current–voltage characteristics of ZnO varistor ceramics and single GB is observed. The percolation model of Shklovskii–De Gennes is applicable for the description of a disorder in ZnO varistor ceramics. The degree of the disorder in ZnO varistor ceramics is not dependent on the duration of dc degradation at least at degradation time below 60 h. At voltages close to the onset of a highly nonlinear region of current–voltage characteristic the correlation radius of infinite cluster is ∼ 5 times greater than the average grain size.