Effect of MoO₃ HTL on the Performance of ITO/ZnO CQDs/F8BT:TIPS-Pentacene/MoO₃/Ag UV-Visible Photodetector

The n-type zinc oxide (ZnO) colloidal quantum dots (CQDs) and p-type blended poly(9,9-dioctylfluorene-alcohol-benzothiadiazol) (F8BT):6,13-bis (tri-isopropyl-silylethynyl) pentacene (TIPS-P) nanocomposite-based heterojunction fabricated on indium tin oxide (ITO)-coated substrate are explored for ultraviolet (UV)-visible photodetection. The effect of MoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> hole-transporting layer (HTL) on the performance of the proposed ITO/ZnO CQDs/F8BT:TIPS-P/MoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub>/Ag photodetector structure has been investigated. Under -1 V reverse bias, the maximum responsivity and specific detectivity were improved in the UV region from 29.60 to 70.20 A/W and from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$6.35\times 10^{{12}}$ </tex-math></inline-formula> Jones to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.97\times 10^{{13}}$ </tex-math></inline-formula> Jones at ~385 nm (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$17.43~\mu $ </tex-math></inline-formula>W/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> intensity), respectively, by using the MoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> HTL in the device. On the other hand, the maximum responsivity and specific detectivity were improved, respectively, from 13.68 to 40.92 A/W and from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.93\times 10^{{12}}$ </tex-math></inline-formula> to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.08\times 10^{{13}}$ </tex-math></inline-formula> Jones in the visible region at 470 nm (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$35.94~\mu $ </tex-math></inline-formula>W/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> intensity) due to the use of the MoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> HTL under -1 V reverse bias.