Reliability and Process Scalability of TiO<sub>2</sub>/Porous Silicon-Based Broadband Photodetectors
B Sharmila, Priyanka Dwivedi
Abstract
This paper presents the reliability and process scalability aspects to fabricate efficient broadband photodetectors based on titanium dioxide (TiO2)/porous silicon (P-Si). Here we have compared the performance and photoresponse of the TiO2/P-Si photodetectors with the P-Si photodetectors. The photosensing performance of the fabricated photodetectors were tested in the broadband spectrum (ultraviolet (UV) to near infrared (NIR)) at room temperature (RT). The TiO2/P-Si photodetectors showed more reliable, repeatable and reproducible results at room temperature (RT). The TiO2/P-Si photodetectors showed a photoresponsivity of ~820 mA/W and detectivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$5.2\times 10\,\,^{\mathrm{ 10}}$ </tex-math></inline-formula> Jones. The photoresponsivity value for TiO2/P-Si is ~8 times higher than the P-Si based photodetectors. Moreover, the TiO2/P-Si photodetector offers rise/fall times of 11/14 ms with excellent repeatability and reproducibility. Further, the TiO2/P-Si photodetector’s reliability test was conducted from 293 K to 400 K. The TiO2/P-Si photodetector offered improved, reliable, repeatable, and stable results at 400 K. The aforementioned results proved that the highly efficient TiO2/P-Si photodetector could be useful for real time optical sensing applications.