Reliability and Process Scalability of TiO2/Porous Silicon-Based Broadband Photodetectors

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
$5.2\times 10\,\,^{\mathrm{ 10}}$
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.