Black phosphorus has been considered as one of the most capable two-dimensional materials for use in optoelectronic nanodevices due to its intrinsic layered nature structure, high mobility of carrier, and tunable bandgap. But its low light absorption prevents its use in high-efficiency photodetectors. In this study, the circular Au/Pd antenna-assisted black phosphorus mid-infrared photodetector which significantly improves the detection performance in comparison with BP photodetectors without antenna has been proposed. By integrating a circular Au/Pd antenna on the BP surface, the light-BP interaction was significantly increased. The simulation results demonstrate that metallic antenna structures improve both light absorption and photocarrier collection in BP phosphorus detectors. The numerical result shows that the photocurrent of the mid-infrared antenna-assisted BP detector was 5 times larger than that of BP photodetector without antennas.

Graphene-ZnO nanohybrid thin films were prepared by the spray pyrolysis technique at 350 °C with graphene nanoplate concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 wt.% deposited on quartz and silicon substrates. The structural and electrical properties have been investigated. XRD results show that the films have a hexagonal wurtzite polycrystalline structure. AFM images showed how the grains are distributed and arranged on the surfaces and illustrated the effect of graphene concentration on the properties of the film by measuring the roughness and grain size. FESEM showed that the surface of the film without graphene is covered with high-packing hexagonal grains with a narrow grain size distribution. At a higher graphene content of 0.5 wt.%, graphene nanoplates distributed within the ZnO matrix were observed. The current-voltage characteristics of the heterojunction show a typical rectification behavior. The photocurrent under illumination measurement has increased gradually with increasing light intensity and graphene concentration. The capacitance-voltage characteristics show that the built-in potential barrier (Vbi) value ranges from 0.65 V for ZnO/Si to 0.3 V for G-ZnO/Si with 0.5 graphene. The spectral responsivity of the photodetector was enhanced for the G-ZnO hybrid at 0.5 graphene.

In this paper, pyramidal shaped GaN-based quantum dots (QDs) with different sizes in each layer, surrounded by 𝐴 𝑙 0. 2𝐺 𝑎 0. 8𝑁 is proposed for infrared photodetector mainly to enhance the detector performance. In this model, we are considering the QDs sizes’ distribution to calculate all parameters instead of using Poisson distribution to express the inhomogeneous broadening just in the absorption coefficient. To model the performance of the devices, the Schrö dinger equation has been solved using the effective mass approximation; then, the absorption coefficient, the gain, the responsivity, the electron mobility, the dark current, and the detectivity as a function of temperature for different biases are obtained. Significant improvements in the optical behavior are seen in the modeled results at T = 220 K.

Electrical and photo response properties of a Al/porous silicon/crystalline silicon/Al structure (Al/PSi/Si/Al) are investigated under irradiation of Nd: YAG laser pulses. The effect of Nd-YAG laser irradiation on the morphological and structural properties of a porous silicon layer is also demonstrated. The porous Si layer is synthesized on a single crystalline p-type Si using electrochemical etching in aqueous hydrofluoric acid at a current density of 20 mA/cm2 for a 40-min etching time. The structure of the porous layer is investigated using atomic force microscopy and optical microscopy. The electrical properties and photo detector figures of merit (responsivity, detectivity, and carrier lifetime) are found to be dependent on the laser fluence.