Current-voltage Characteristics Of Structures Research Articles

Investigation of electrical properties of photosensitive structures of reduced dimension based on silicon coated with rare earth fluorides

In this paper, we consider the effect of porous silicon and dysprosium fluoride films on the current-voltage characteristics of low-dimensional photosensitive structures based on silicon. The processes of creating and studying the resulting photosensitive structures are described. The current-voltage characteristics of the structures before and after coating are given. The study found a positive effect of porous silicon and dysprosium fluoride coating on the current-voltage characteristics of structures both with and without porous silicon. Values of the optimal thickness of the dysprosium fluoride coating for porous photosensitive structures are obtained. It is shown that dysprosium fluoride coatings do not always have a positive effect on such parameters of photosensitive structures as short-circuit current and open-circuit voltage, since this is due to the non-uniformity of film deposition on the surface of the structure.

Sensitivity of porous silicon-ferromagnetic metal composites to molecular hydrogen adsorption

The effect of molecular hydrogen adsorption on the current-voltage characteristics of structures based on porous silicon (por-Si) nanocomposites with nickel (por-Si-Ni) and cobalt (por-Si-Co) has been studied. The samples exhibit significant sensitivity to molecular hydrogen adsorption at a temperature of about 150°C. A model is proposed that explains the observed phenomena.

Effect of atmospheric-air pressure on charge transport in structures with oxidized porous silicon

The electron-transport processes in structures with oxidized porous silicon (OPS) are investigated during adsorption and desorption of polar molecules from atmosphere when the air pressure varies. It is shown that the cause of the existence of the open-circuit voltage in Pd-OPS-p+-Si-Al structures in the initial state is the surface-charge change on the Pd-OPS interface due to the polar-molecule adsorption from atmospheric air. The desorption of atmospheric-air molecules leads to a change in the current-voltage characteristics of structures, growth of the metal-OPS barrier in samples with the Schottky barrier, and initiation of current instabilities. The nanocrystalline nature of OPS manifests itself in the charge-carrier localization in quantum dots (QDs) during desorption in samples with space-charge-limited currents.

Current-voltage characteristics of structures with a porous silicon layer at adsorption of carbon monoxide

The current-voltage characteristics of structures with a layer of porous silicon of 73% porosity were measured at adsorption of gas (carbon monoxide) at room temperature. Estimations are performed of the height of potential heterobarrier at the interface between porous silicon and p +-type single-crystal silicon, of the perfectness factor and the resistance of a layer of porous silicon in air, in air with 0.4% CO, and in air with 2% CO. Physical causes explaining the experimental data are discussed.

Perpendicular transport ina-Si:H/a-SiNx:H single- and double-barrier structures

Current bumps in the current-voltage characteristics of amorphous semiconductor double-barrier structures have previously been associated with a resonant-tunneling process through quantized levels in the well region of the structure. We investigate the perpendicular transport through single-(SB) and double-barrier (DB) structures of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon nitride (a-${\mathrm{SiN}}_{\mathit{x}}$:H) grown by glow discharge. The current-voltage characteristics of these structures are studied at 295 and 77 K. Current bumps are observed in the I-V characteristics of both SB and DB structures, which suggests a different transport mechanism than previously proposed. We propose that the first current bump is simply a transition from a low-field (space-charge-limited) transport mechanism to a high-field (multiple-hopping) transport mechanism. The additional bumps are associated with the energy dependence of the density of localized states in the a-${\mathrm{SiN}}_{\mathit{x}}$:H and a-Si:H.