High-Detectivity β-Ga2O3 Microflake Solar-Blind Phototransistor for Weak Light Detection

This letter reports a high-performance solar-blind phototransistor based on N-2-annealed beta-Ga2O3 microflake for weak light detection. The phototransistor exhibits an ultra-low dark current of 27 fA, a high external quantum efficiency of 8.36 x 10(7) %, a photo-to-dark-current ratio of 1.08 x 10(7), a low power consumption of 2.92 pW, and a narrow-band response with a cut off wavelength of 263 nm. In addition, the spectral selectivity can be well modulated by the gate bias and reaches a maximum R-240/R-400 ratio of 2.4 x 10(4). Especially, an ultra-high responsivity (R) of 1.71 x 10(5) A/W and a record-high detectivity (D*) of 1.19 x 10(18) Jones have been achieved under 254nm illumination of 4.1 mu W/cm(2). The superior weak-light-detection performance of the device makes it one of the best Ga2O3 detectors towards solar-blind photodetection application.

Automated summary

This letter presents a high-performance solar-blind phototransistor based on N-2-annealed beta-Ga2O3 microflake for weak light detection. The device exhibits ultra-low dark current, high external quantum efficiency, and narrow-band response, achieving ultra-high responsivity and record-high detectivity under specific illumination conditions. The device demonstrates superior weak-light-detection performance for solar-blind photodetection applications.