Expanding the spectral responsiveness of photodetectors via the integration of TiO2 and Y2O3 quantum dots prepared by laser ablation in liquid

This research aims to improve the performance of photo detectors by fabricating and evaluating three types of Nano detectors based on titanium oxide (TiO₂) and yttrium oxide (Y2O3) using the laser ablation technique. The detectors were prepared according to the following compositions: Ag/ TiO₂ / n-Si/Ag, Ag/ Y2O3 / n-Si/Ag, Ag/ TiO₂ / Y2O3/n-Si/Ag, and were studied using XRD, FESEM, AFM, UV-Vis, FTIR, in addition to evaluating their performance through measurements of specific detectivity (D*) and spectral response (R). The results showed that the combination of TiO₂ and Y2O3in the Ag/ TiO₂/ Y2O3/n-Si/Ag detector performed the best in terms of specific detectivity and spectral response in (Ultraviolet, Visible and Near Infrared) range, making it the most efficient from other detectors. Its superiority is due to the cumulative effect of incorporating TiO₂ and Y2O3, which reduced the effective energy gap and improved the efficiency of photon absorption and electron transfer. Although TiO₂ showed good UV and NIR absorption but it has low absorption in the visible spectrum owing to its broad energy gap of 3.3 eV when used alone. The detector based on Y2O3alone in the Ag / Y2O3/n-Si/Ag did not yield significant improvement compared to the combination of TiO₂ and Y2O3in the Ag/ TiO₂/ Y2O3/n-Si/Ag detector, highlighting the role of Y2O3as a key material in enhancing the performance of photodetectors. This study confirms that yttrium oxide (Y2O3) is a promising material for the fabrication of highly efficient photodetectors due to its unique electronic and optical properties, which increases the sensitivity of the photodetector in (visible and near infrared) range. The outcomes also show that laser ablation technique is an effective approach for preparing nanomaterials with high precision, which enhances their structural and optical properties. Given these results, it may be recommended that amalgamation of TiO₂ and Y₂O₃ be adopted as a base material in the design of future photodetectors, with additional processing techniques being explored to improve the performance of TiO₂ and reduce its recombination rates. This study also opens up new avenues for the development of advanced nanophotodetectors with novel fabrication techniques, enhancing their applications in the fields of environmental sensing, optical communications, and advanced electronic.