Amorphous IGMO/IGZO heterojunction thin-film transistors with enhanced ultraviolet detection performance

Amorphous InGaZnO (IGZO) is a potential candidate for integrated circuits based on thin-film transistors (TFTs) owing to its low-temperature processability and high mobility. Amorphous InGaMgO/InGaZnO (IGMO/IGZO) heterojunction was deposited and TFTs based on IGMO/IGZO heterojunction were fabricated in this report. The energy band at the IGMO/IGZO heterojunction was characterized, and the potential well at the interface of IGZO is critical to the enhanced ultraviolet detection of the IGMO/IGZO heterojunction. Furthermore, the TFTs based on IGMO/IGZO heterojunction exhibited a high responsivity of 3.8 × 10³ A/W and a large detectivity of 5.2 × 10¹⁴ Jones under 350-nm ultraviolet illumination, which will also benefit for fabrication of monolithic ultraviolet sensing chip.