Li, Xiao-Xi; Zeng, Guang; Li, Yu-Chun; Zhang, Hao; Ji, Zhi-Gang; Yang, Ying-Guo; Luo, Man; Hu, Wei-Da; Zhang, David Wei; Lu, Hong-Liang

NPJ FLEXIBLE ELECTRONICS

2022, 6,

Li, Xiao-Xi; Zeng, Guang; Li, Yu-Chun; Zhang, Hao; Ji, Zhi-Gang; Yang, Ying-Guo; Luo, Man; Hu, Wei-Da; Zhang, David Wei; Lu, Hong-Liang

Deep-ultraviolet (DUV) phototransistors have shown great potential applications in UV imaging, artificial intelligence, and wearable optoelectronics. Among a large number of wide bandgap semiconductors, the quasi-two-dimensional beta-Ga2O3 is considered as an ideal candidate for DUV photodetector applications. Herein, we report a high responsivity (R) and fully flexible Ta-doped beta-Ga2O3 DUV phototransistor which exhibits outstanding optoelectrical properties with a high R of 1.32 x 10(6) A/W, a large detectivity of 5.68 x 10(14) Jones, a great photo-to-dark current ratio of 1.10 x 10(10)%, a high external quantum efficiency of 6.60 x 10(8) %, and an ultra-fast response time of similar to 3.50 ms. Besides, the flexible Ta-doped beta-Ga2O3 device also displays high reliability and mechanical flexibility that can sustain well after over 1 x 10(4) bending cycles. Moreover, high-contrast imaging of UV light was obtained on the flexible DUV detector arrays, which can be efficiently trained and recognized by an artificial neural network. Our findings offer a perspective to develop wearable optoelectronics and UV imaging based on high-performance flexible beta-Ga2O3 DUV phototransistors, providing an inspiration for the future work in artificial intelligence and bionic robot fields.