Fig. 1

Device structure and electro-optical characterization. a Device diagram of the PbS QDs/IGZO phototransistor, and corresponding cross-sectional TEM image. The scale bar is 200 nm. Here, the device film structure is PbS QDs (70 nm)/Al (100 nm)/Ti (10 nm)/IGZO (30 nm)/SiO₂ (200 nm) with Si substrate as gates. b Responsivity-wavelength plot of phototransistors with PbS QDs passivated by different length alkanedithiol ligands, varying from EDT to DDT. c Responsivity-bandwidth plot for phototransistors passivated with different length alkanedithiol ligands. Both responsivity measurements are conducted with V_gs = 5 V and V_ds = 5 V