Abstract
In this study, we have covered a porous silicon (PS) layer with tin dioxide (SnO2) nanostructured via a pulsed laser deposition process to produce a broadband photoresponse device. The impact of laser fluence on the optical, electrical, and structural characteristics of the fabricated photodetector was identified. The optical features analysis indicated that the SnO2 films covered on porous silicon have a direct energy gap varying from 3.62 to 3.67 eV as a function of laser fluence. The X-ray diffraction investigation proved that the SnO2 nanostructure has a tetragonal rutile nature. The Field-emission scanning electron microscopy emphasised that produced SnO2 nanostructures have a mean size of 81.76–98.68 nm, and nanoparticle agglomeration was remarked. The photoluminescence emissions of SnO2 nanostructure placed on porous silicon displayed a variety of overlapping intensities in the near-ultraviolet/visible spectrum between 369 and 506 nm, while the intense red band decreased in intensity and shifted towards longer wavelengths. Fourier-transformed infrared spectroscopy investigation indicates the existence of the Sn-O-Si bond in the formed structure.
The dependence of the optoelectronic characteristics of PS/n-Si and SnO2/PS/n-Si photodetector on laser fluence has been performed. Produced heterojunctions have remarkable rectification properties with ideality factors ranging from 2.27 to 2.91, relying on the laser fluence. The spectral responsivity analysis showed that SnO2/PS/n-Si photodetectors exhibit three response bands at ∼366 nm, ∼621 nm, and ∼806 nm, regarding the highest responsivity of 0.21 A/W, 0.33 A/W, and 0.43 A/W, respectively. The findings suggest that SnO2/PS/n-Si heterojunction photodetectors are suitable for developed ultraviolet–visible light detection enhanced photodiodes that are cost-effective and convenient for use in wearable and portable devices without expensive extra gadgets.
Authors:Ali J Hadi, Uday M Nayef, Falah AH Mutlak, Majid S Jabir