Fig. 2

Overall device structure and crystal structure analysis of Te/Se. (a) Cross-sectional TEM image of a dual-gate Te/Se phototransistor. (b) EDS mapping images of elemental distribution. (c) HR-TEM image showing the bottom gate, channel layer, and passivation layer. (d) HR-STEM image of a Te/Se alloy. The red circles represent Te/Se atoms. (e) FFT pattern of Te/Se alloy.