Hafnia-based oxide enhanced Ga2O3-based photodetectors via band engineering with ultralarge responsivity

Ga2O3 thin films have emerged as an excellent choice as a photoactive layer, with specifically significant prospects for detection within the solar blind range, due to its large direct bandgap, high sensitivity and outstanding stability. Yet, achieving a high responsivity at low supply voltage has proven to be challenging. Here, we fabricated and characterized high-performance vertical-structured beta-Ga2O3 photodetectors with epitaxial Hf(0.5)Zr0.5O(2 )as an interlayer that demonstrated a very high responsivity of up to 148 A W(-1 )at a low voltage of 9.8 V. The polar Hf0.5Zr0.5O2 interlayer and low dark current density characteristics enhance the detection performance at low supply voltage and ultralow light intensity. These results provide a path towards high-performance and highly integrated deep-ultraviolet detection devices, beyond conventional ones in terms of application.