Amorphous Ga2O3 Thin-Film Phototransistors for Imaging and Logic Illustration

Amorphous Ga 2 O 3 (a-Ga 2 O 3 ) thin-film phototransistors were fabricated by sputtering and achieved excellent solar-blind detection properties with superhigh responsivity of 2.0 × 10 5 A∙W -1 , ultrahigh detectivity of 4.9 × 10 18 Jones, high external quantum efficiency of 9.9 × 10 7 %, and high photo-to-dark current ratio of 2.9 × 10 8 . These values are considerably high compared with those of the reported a-Ga 2 O 3 phototransistors, and are comparable to or even better than those of the reported high-performance crystalline β-Ga 2 O 3 phototransistors. A 10 × 10 a-Ga 2 O 3 thin-film phototransistor array was fabricated, showing a clear "SDU" pattern with high contrast. In addition, the light control logic AND and OR gates based on a-Ga 2 O 3 thin-film phototransistors were realized by utilizing two light spikes as logic input signals. Our work demonstrates that the a-Ga 2 O 3 thin-film phototransistors have great potential in large area photosensitive circuits with high detection sensitivity and high signal-to-noise ratio.